Turning pain into strength: prosocial behaviours in coping with trauma

ABSTRACT

Background: Various coping strategies have been shown to alleviate the negative effects of trauma, yet the significance of prosocial behaviour in this realm has been notably underexplored. The present study explored the hypothesis that engaging in prosocial behaviour mitigates the impacts of trauma by promoting a sense of competence and relatedness, post-traumatic growth (PTG), and reconstruction of meaning.

Methods: Three consecutive studies were conducted with college students to compare differences in consequence of prosocial behaviours between a trauma group and a control group. Study 1 (N = 96) used self-reported experiences of traumatic vs non-traumatic events; Study 2 (N = 43) used exposure vs. no exposure to video of an earthquake; Study 3 (N = 20) used a randomized controlled trial (RCT) of a prosocial-themed intervention vs. no intervention. Outcomes in all studies were assessed by self-report questionnaires.

Results: Trauma damaged participants’ sense of competence and meaningfulness. Prosocial behaviour relieved the impact of trauma on meaning, specifically manifested in the individuals' sense of meaningfulness and their search for meaning. Group interventions with a prosocial theme (based on effect size results) reduced post-traumatic stress disorder (PTSD) and enhanced PTG in victims. The promoting effect on PTG persisted a month later, and its enhancing effect on meaning manifested with a delay.

Conclusion: Prosocial behaviour can potentially serve as a beneficial strategy for individuals coping with trauma because it helps enhance meaning and promotes PTG in victims. This conclusion is supported by laboratory experiments and a tentative small-scale intervention study, which provide an innovative perspective for future trauma interventions.

HIGHLIGHTS

• Prosocial behaviour can potentially serve as a beneficial strategy for individuals coping with trauma.

• Prosocial behaviour relieved the impact of trauma on meaning.

• Prosocial-themed intervention reduced PTSD and enhanced PTG in victims (based on effect size results).

Antecedentes: Se ha demostrado que diferentes estrategias de afrontamiento pueden mitigar los efectos negativos del trauma; no obstante, la importancia de la conducta prosocial en este ámbito ha sido notablemente poco explorada. Este estudio evaluó la hipótesis que el participar en conductas prosociales reduce el impacto del trauma al promover una sensación de suficiencia y cercanía, crecimiento postraumático (CPT) y la reconstrucción de significados.

Métodos: Se realizaron tres estudios consecutivos en estudiantes universitarios para comparar las diferencias de las consecuencias de las conductas prosociales entre un grupo expuesto a trauma y un grupo control. El primer estudio (n = 96) empleó experiencias autorreportadas traumáticas en comparación al autorreporte de las no traumáticas; el segundo estudio (n = 43) empleó la exposición al video de un terremoto en comparación a la no exposición a este; el tercer estudio (n = 20) empleó un ensayo clínico controlado de una intervención con temática prosocial en comparación a la no intervención. Los resultados en todos los estudios se evaluaron mediante cuestionarios de autorreporte.

Resultados: El trauma comprometía la sensación de suficiencia y el sentido de significancia de los participantes. La conducta prosocial mitigó el impacto del trauma sobre los significados, específicamente en aquellos asociados al sentido de significancia de la persona y en su búsqueda de significado. Las intervenciones grupales con temática prosocial redujeron el trastorno de estrés postraumático (TEPT) e incrementaron el CPT en las víctimas, evidenciado en los resultados del tamaño del efecto. El efecto promotor del CPT persistió un mes después, y sus efectos potenciadores sobre los significados se manifestaron con dilación.

Conclusiones: La conducta prosocial puede potencialmente servir como una estrategia beneficiosa para individuos que afrontan el trauma debido a que ayudan a mejorar los significados y a que promueven el CPT en las víctimas. Esta conclusión se sustenta en experimentos de laboratorio y en un estudio provisorio de intervención a pequeña escala, el cual brindó una perspectiva innovadora para futuras intervenciones en trauma.

KEYWORDS:

• Trauma
• prosocial behaviour
• coping
• competence
• meaningfulness
• post-traumatic growth

PALABRAS CLAVE:

• Trauma
• conducta prosocial
• afrontamiento
• suficiencia
• sentido de significancia
• crecimiento postraumático

1. Introduction

Various sudden, threatening, or catastrophic events are common occurrences, whether they are incidents experienced as a group, such as natural disasters and wars, or experienced individually, such as traffic accidents, severe illnesses, domestic violence, and abuse (Xu, 2018). Furthermore, individuals with a history of trauma may experience ongoing feelings of intense fear and helplessness (American Psychiatric Association, 2013), potentially leading to post-traumatic stress disorder (PTSD; Zhou et al., 2017), interpersonal conflict, aggression, impulsivity, and even antisocial behaviours (Wilson et al., 2009), which can ultimately impair psychological and social functioning.

Recovery from trauma can also produce positive changes (Xu, 2018) through an individual’s post-traumatic growth (PTG). PTG includes positive changes in self, relationships, and a philosophy of life (Tedeschi & Calhoun, 1996, 2004); there may be a deepening of self-awareness, enhancement of empathy and trust in others, and improved ability to help others and cooperate with neighbours (McMillen, 2004). Trauma recovery may also have societal benefits beyond the individual level (Xu, 2018), which contributes to strengthened group cohesion (McMillen, 2004) and the promotion of prosocial behaviours (Vollhardt & Staub, 2011). Prosocial behaviours (e.g. helping others, altruism, donations, and cooperation; Greener & Crick, 2001) help promote mental health and interpersonal harmony, reduce social unrest, and maintain social stability (Ye et al., 2020).

1.1. The relationship between trauma and prosocial behaviour

Staub and Vollhardt (2008) proposed the concept of Altruism Born of Suffering (ABS), the idea that after experiencing suffering, people often reshape their sense of meaningfulness in life and become more caring and helpful. This phenomenon is confirmed by empirical studies, which show that suffering a trauma increases prosocial behaviours such as donating money, donating blood, participating in rescue, and volunteering (for a review see Xu, 2018). For example, in questionnaire interviews conducted after Hurricane Hugo, victims reported providing higher levels of tangible, informational, and emotional support, as well as more helping behaviours, compared with those not affected by the disaster (Kaniasty & Norris, 1995). Furthermore, Vollhardt and Staub (2011) found that compared with individuals who had not experienced a natural disaster, those who had suffered such trauma exhibited more prosocial attitudes and behaviours, including everyday volunteering activities and short-term emergency helping. Rao et al. (2011) conducted a questionnaire survey with victims of the Wenchuan earthquake and found that as the disaster’s impact on residences intensified, there was a corresponding increase in prosocial behaviour, as evidenced by the Dictator Game and anticipated volunteering activities. Indeed, during the COVID-19 outbreak, people all over the world donated money and materials, and tens of thousands of medical workers rushed to the frontline of the fight against the pandemic; researchers conducted a text analysis of the content of posts by 387,730 Weibo users and found that the severity of the pandemic predicted prosocial tendencies (Ye et al., 2020).

A similar phenomenon has been found in human-caused disasters. After the 9/11 terrorist attacks in the United States, a questionnaire study found that 35%–62% of college students reported having donated blood or money for the victims (Piferi et al., 2006). Stidham et al. (2012) used qualitative descriptive methods to find that survivors of sexual violence help others in a variety of ways. The ABS phenomenon has even been shown in children during wartime, with an increase in prosocial behaviours as measured by the prosocial behaviour rating scale (Raboteg-šaricet al., 1994). An increase in traumatic events was associated with more frequent short-term acts of helping and long-term volunteering among a cohort of college students, according to the results of the online questionnaire survey conducted by Frazier et al. (2013). Thus, ABS has been demonstrated in several studies of people affected by natural and human-caused disasters. The results provide strong evidence that many people in these groups display post-trauma prosocial behaviour.

1.2. Post-trauma prosocial behaviour as a coping strategy

Coping strategies are key factors in recovery from trauma (Rajandram et al., 2011). Midlarsky (1991) asserted that helping others is an effective coping strategy for victims, and proposed three paths by which prosociality can promote positive changes: increase self-cognition, support social integration, and enhance a sense of meaning.

First, prosocial behaviour as a coping strategy in response to trauma can occur through increases in positive self-cognitions, such as an increased sense of self-competence (Bandura et al., 2001; Midlarsky, 1991). Self-competence refers to individuals' feeling that they are capable and have the opportunity to exercise and express their talent (Liu et al., 2013). A sense of self-competence is important because victims are often seen as weak, whereas helpers are seen as having ability or resources (Griskevicius et al., 2010). The real or perceived unequal needs and abilities might encourage victims to help others to reduce this imbalance and re-establish their sense of competence and worth (Midlarsky, 1991).

Second, prosocial behaviour as a coping strategy can promote social integration and social bonding (Midlarsky, 1991; Poulin et al., 2013). Because helpers are viewed positively, the norms of reciprocity and mutual social support promote victims’ prosociality as a way to cope after adversity (Vollhardt & Staub, 2011). The desire for bonding is a basic psychological need, and reflects the social integration which requires the establishment and maintenance of a minimum quality and quantity of social connections (Baumeister & Leary, 1995). Prosocial behaviours in victims are more effective in promoting health and well-being than receiving social support (Brown et al., 2003).

Third, prosocial behaviour can create or enhance a person’s perception of meaning in life (Klein, 2017). The concept of Shattered Assumptions (Janoff-Bulman, 1989) is that the pain of traumatic events destroys victims’ existing system of meaning, forcing victims to view the world as meaningless, disordered, unsafe, unpredictable, and uncontrollable. Therefore, many victims could, through prosocial behaviour, rebuild their belief in a meaningful world and rediscover meaning in life (Janoff-Bulman, 1989).

To summarize, many studies have found that the association between traumatic experiences and prosocial behaviour is intricate and intimate. Prosocial behaviours may serve as a coping strategy to reduce the negative impact of trauma. However, although several theories, as discussed above, suggest how prosocial behaviour alleviates the negative effects of trauma, few studies have tested these theories empirically.

1.3. Present study

The present research comprised three separate studies, designed in view of the hypothesis that prosocial behaviour is an effective strategy for coping with trauma. Study 1 and Study 2 used different trauma-arousal paradigms (i.e. autobiographical recall, Study 1; trauma film, Study 2) and prosocial measurement methods (i.e. single donation task, Study 1; multi-round charitable donation task, Study 2) to explore the positive effects of post-traumatic prosocial behaviour. Study 3 sought to verify whether a prosocial-themed group intervention effectively reduces the harm caused by traumatic events and promotes positive changes.

2. Study 1

Study 1 investigated the impact of an autobiographical recall paradigm on evoking traumatic experiences, and assessed the role of prosocial behaviour in trauma coping. Specifically, it examined how such behaviour helped enhance participants’ sense of meaningfulness and sense of competence, and diminished their search for meaning. Participants knew that at the end of the study they would receive a small financial award; prosocial behaviour was assessed by a self-selectable prosocial situation to decide whether to donate half of that award to a charity for poor children.

2.1. Methods

2.1.1. Participants

The participants were 96 undergraduate and graduate students (48 male and 48 female; M_age = 23.99, SD = 7.18), who were recruited offline from Zhejiang University of Technology and were randomly divided into the trauma group (n = 53) or the control group (n = 43). Participation was voluntary, and the participants signed an informed consent form before the experiment. They were told that at the end of the study they would be paid 30 Renminbi (RMB) to compensate them for their time and effort. The study was approved by the research ethics committee at Zhejiang University of Technology.

2.1.2. Experimental materials

Positive and Negative Affect. The Positive and Negative Affect Schedule (PANAS; Watson et al., 1988) includes two subscales: positive affect (e.g. enthusiastic, interested, excited) and negative affect (e.g. distressed, upset, hostile), which were used to assess the intensity of a participant’s mood. Each subscale consists of ten items, rated on a 5-point Likert scale (1 = ‘very slight or not at all’ to 5 = ‘extremely strong’). Higher scores indicate that participants experienced a more intense positive or negative mood. This study used the Chinese version of the PANAS (Huang et al., 2003), which has demonstrated good reliability and validity.

Sense of Competence. A sense of competence was measured with the Competence Needs Subscale of the Basic Psychological Needs Scale (BPNS), which was developed by Gagné (2003) and later translated into Chinese by Liu et al. (2013). Competence refers to an individual’s feeling of capability and the opportunity to exercise and demonstrate their abilities in interactions with their environment (Liu et al., 2013). This subscale was used to measure the extent to which participants’ psychological need for competence was satisfied (i.e. a sense of competence). It comprised six items, rated on a 7-point Likert scale (1 = ‘not at all true’ to 7 = ‘very true’). Examples of items include, ‘Often, I do not feel very competent’ (reversed) and ‘Most days I feel a sense of accomplishment from what I do.’ Higher scores on the subscale represent a greater sense of competence. Previous studies have confirmed the good reliability and validity of this subscale (Liu et al., 2013).

Meaning. Meaning in this study consisted of the process of meaning-seeking (named ‘search for meaning’) and the results of this process (named ‘sense of meaningfulness’). To assess this, we used the Meaning in Life Questionnaire (MLQ) originally developed by Steger et al. (2006) and later revised for the Chinese context by Liu and Gan (2010). It comprises two distinct subscales: MLQ Search (MLQ–S) and Presence (MLQ–P), which were used to measure the search for meaning (referring to individuals seeking meaning and purpose in their lives) and presence of meaning (indicating individuals perceive their lives as meaningful and purposeful). The questionnaire consists of nine items, each rated on a 7-point Likert scale (1 = ‘absolutely untrue’ to 7 = ‘absolutely true’). Examples of these items include, ‘I am looking for something that makes my life feel meaningful’ and ‘I am always looking to find my life’s purpose' (both representing a search for meaning) as well as, ‘I understand my life’s meaning' and ‘My life has a clear sense of purpose’ (both representing presence of meaning). A higher score on each subscale signifies a greater degree of search for meaning or sense of meaningfulness. The MLQ has demonstrated robust reliability and validity in its measurements (Liu & Gan, 2010).

The autobiographical trauma-recall paradigm (Davis & McKearney, 2003; Griskevicius et al., 2010) was used to evoke traumatic experiences; participants in each group were asked to recall an event and record their emotional experiences related to the recalled event. The instructions for the trauma group were as follows: Please take three minutes to recall a specific event that was unusual, sudden, threatening, or catastrophic, such as an event in which you experienced or witnessed an actual or threatened death, serious injury, sexual violence, or social neglect (e.g. lack of adequate care during childhood). The instructions for the control group were as follows: Please take three minutes to recall an event such as riding your bike, preparing for an exam, brushing your teeth in the morning, or something else that happens in your daily life. As part of the manipulation, participants in both groups were asked to write at least five sentences to describe the event in as much detail as possible, including the time, place, and process of the event, feelings and thoughts at the time, and the impact on them of the event.

The independent variable for prosocial behaviour was defined as a donation group and a non-donation group. Participants were shown the website of the Wheat Field Project, an actual public health programme in China for children living in poverty. Participants were told that they would be receiving monetary compensation for their time and effort at the end of the study, and were asked if they were willing to donate half of the money to the Wheat Field Project. Yang and Kou (2015) found that only self-selected prosocial behaviours improved happiness, so the instructions emphasized that the donations were completely voluntary. After the experiment, all the donations were sent to the charity in the name of the participants. Those who donated half of their award were included in the donation group after the experiment, while those who did not donate awards were included in the non-donation group.

2.1.3. Procedure

The study adopted a 2 (group: trauma group, control group) × 2 (prosocial behaviour: donation group, non-donation group) between-subjects design. The dependent variables were sense of competence and meaningfulness, and search for meaning.

Participants were randomly assigned to the trauma group or control group. They recalled traumatic events (trauma group) or daily events (control group) according to the procedures of the autobiographical trauma-recall paradigm. The participants then completed the PANAS as a manipulation check. After that, the Wheat Field Project was introduced to all participants, and they were asked whether they were willing to donate half of their award in this experiment to the children in impoverished mountainous areas. Finally, the participants completed questionnaires to assess their sense of competence and meaningfulness, and their search for meaning.

After the experiment, the participants were paid according to their actual income (that is, the participants who agreed to make a donation received half the participation award). A brief interview and assessment were conducted to ensure that the participants were no longer affected by the traumatic event that they had recalled during the study.

2.2. Results

As a manipulation check, the emotional state of the trauma group and control group were compared after the autobiographical recall task. The PANAS negative affect scores were significantly higher in the trauma group (M = 2.65, SD = 0.80) than in the control group (M = 1.29, SD = 0.30), t(69) = 11.37, p < .001, d = 2.25. These two groups did not differ in positive affect (M = 2.18, SD = 0.77; M = 2.31, SD = 0.77), t(94) = −0.85, p = .40. This result implies that the trauma manipulation, which was implemented through the autobiographical recall task, significantly influenced negative affect, and effectively evoked the recall of traumatic experiences.

Analysis of variance was conducted with sense of competence, search for meaning, and sense of meaningfulness as dependent variables. The descriptive statistics for each group are shown in Table 1. The main effect of trauma was significant for sense of competence, F(1,92) = 4.09, p = .05, η_p²= 0.04, with lower scores in the trauma group (M = 4.36, SD = 0.84) than in the control group (M = 4.62, SD = 0.75; t(94) = −2.02, p_Bonferroni = .05, d = −0.42), indicating that traumatic experience was associated with a weaker sense of competence. The main effect of prosocial behaviour was nonsignificant, F(1,92) = 0.02, p = .90. However, the interaction effect of trauma and prosocial behaviour on sense of competence was significant (see Figure 1(a)), F(1,92) = 5.41, p = .02, η_p²= 0.06. For a more detailed analysis of simple effects, we employed a Bonferroni post hoc test with a correction for multiple comparisons. The results showed that for the non-donation group, sense of competence in the trauma group was lower than that for the control group (t(37) = −2.83, p_Bonferroni = .04, d = −0.91), whereas, for the donation group, there was no significant difference between the trauma and control groups (t(55) = 0.24, p_Bonferroni = 1.00, d = 0.06). These findings suggested that recall of trauma was associated with reduced sense of competence in a subsequent questionnaire; however, this reduction was attenuated in participants who donated to charity after recalling their trauma.

Figure 1. Plots of interaction effects for (a) Sense of competence and (b) Sense of meaningfulness in Study 1.

Table 1. Mean (M) and standard deviation (SD) for each group in Study 1.

Dependent Variable	Independent Variables	Donation Group (n = 57)	Non-donation Group (n = 39)
Sense of Competence	Trauma Group (n = 53)	4.52 (0.95)	4.12 (0.59)
	Control Group (n = 43)	4.47 (0.73)	4.83 (0.74)
Search for Meaning	Trauma Group (n = 53)	5.26 (1.08)	5.08 (1.19)
	Control Group (n = 43)	5.20 (0.95)	5.00 (1.41)
Sense of Meaningfulness	Trauma Group (n = 53)	4.49 (1.07)	3.94 (1.25)
	Control Group (n = 43)	4.53 (0.95)	4.77 (1.19)

For search for meaning, there was no main effect of trauma, F(1,92) = 0.09, p = .77, nor main effect of prosocial behaviour, F(1,92) = 0.62, p = .44, and no interaction effect, F(1,92) = 0.003, p = .96. This result suggested that neither the traumatic experience nor the donation had an impact on an individual’s meaning-seeking, and that donating behaviour in both groups did not induce changes in searching for meaning.

The main effect of trauma on sense of meaningfulness was marginally significant, F(1,92) = 3.51, p = .06, η_p²= 0.04, with lower scores in the trauma group (M = 4.27, SD = 1.16) than in the control group (M = 4.63, SD = 1.05; t(94) = −1.87, p_Bonferroni = .06, d = −0.39), suggesting that recalling trauma experience threatened the sense of meaningfulness in life. The main effect of prosocial behaviour was nonsignificant, F(1,92) = 0.44, p = .51. The interaction effect of trauma and prosocial behaviour was marginally significant (see Figure 1(b)), F(1,92) = 2.88, p = .09, η_p²= 0.03. Simple effect results showed that for participants who did not donate their rewards, trauma experience did not significantly decrease their sense of meaningfulness compared with the control group, although there was nearly a large effect size between the two groups (t(37) = −2.32, p_Bonferroni = .14, d = −0.75). In the donation group, the sense of meaningfulness was not significantly different between the control group and the trauma group (t(55) = −0.14, p_Bonferroni = 1.00, d = −0.04). These findings indicated that traumatic experience recall was linked to a diminished sense of meaningfulness, as observed in a subsequent questionnaire. However, this reduction was less in participants who donated to charity, which arguably means donating could protect the destructive impact of trauma on a sense of meaningfulness.

2.3. Discussion

Study 1 showed that the autobiographical trauma-recall paradigm effectively elicited the recollection of traumatic experiences and the negative emotions associated with them. Recalling traumatic experiences was found to be associated with a diminished sense of competence and sense of meaningfulness. According to the Shattered Assumptions Theory (Janoff-Bulman, 1989), experiencing a trauma reduces individuals’ positive and optimistic assumptions about themselves and the world, and disrupts positive feelings of self-competence and meaningfulness. Trauma is related to a decrease in positive emotions (Martela et al., 2018), which might weaken individuals’ motivation for engaging in enjoyable activities and diminish their interest in daily activities, potentially contributing to emotional blunting or anhedonia, and ultimately increasing the risk of developing PTSD (Blackburn & Owens, 2015; Kashdan et al., 2007). Childhood trauma (Wilson et al., 2009), war (Kashdan et al., 2007), natural disasters (Zhou et al., 2017), and other traumatic events have been found to have significant negative impacts on individuals. Although the mean differences between the trauma group and the control group in the present study were relatively small for sense of competence and sense of meaningfulness, significant differences were found. Moreover, this was only triggered by the recall of traumatic memories following an experimental paradigm conducted in a controlled laboratory environment, which potentially limited the extent of observed effects of trauma and ecological validity. Future research should investigate both individuals who have just experienced trauma and those who have just recalled trauma, to further confirm the differences in the effects of experiencing versus recalling trauma.

An important finding in our study was that the negative impact of traumatic experience on both sense of competence and sense of meaningfulness in life appeared to be weakened when participants donated to a charitable cause. The hypothesis was partially supported: prosocial behaviour may be effective as a coping strategy in response to the negative effects of trauma, which is consistent with Midlarsky’s (1991) view. When individuals devote themselves to a cause or to loved ones, they are more likely to realize their own value and perceive the potential meanings of life (Frankl, 1985). Prosocial behaviour serves as a mechanism whereby individuals immerse themselves in the broader social context, altruistically seeking welfare for others. This process facilitates the discovery of meaning in life and the reconstruction of confidence in their enduring capabilities, thereby providing a compensatory response to the feelings of meaninglessness and powerlessness induced by trauma. However, in Study 1 we used a dichotomous measure of prosocial behaviour (donation vs. non-donation); therefore, to address this deficiency, we used a more complex and potentially accurate measure of prosocial behaviour in Study 2.

3. Study 2

To substantiate the findings in Study 1 with another paradigm, we used a trauma film paradigm in Study 2 to induce traumatic experiences, while prosociality was measured with a multi-round charitable donation task. Alongside the dependent variables evaluated in Study 1, we incorporated an assessment of a sense of relatedness to examine the role of prosocial behaviour in fostering social integration after experiencing trauma.

3.1. Methods

3.1.1. Participants

We recruited 43 undergraduate and graduate students offline from Zhejiang University of Technology (21 male and 22 female; M_age = 20.30, SD_age = 1.30). By self-report, none of the participants had a history of psychiatric disorder and none had participated in any similar experiments. They signed the informed consent form before the experiment and received a monetary award (Up to 30 RMB) after the experiment.

3.1.2. Experimental materials

The PANAS was used as a manipulation check. The subscales of Competence Needs and Relatedness Needs in the BPNS and the MLQ were used to measure dependent variables. All of these were used in Study 1 except the Relatedness Needs Subscale of the BPNS, described here.

Sense of Relatedness. The Relatedness Needs Subscale of the BPNS was developed by Gagné (2003) and later translated into Chinese by Liu et al. (2013) to measure participants’ sense of relatedness. Relatedness refers to the individual’s feeling of caring for others and being cared for by others, experiencing a sense of security from being part of other individuals and groups (Liu et al., 2013). This subscale was used to measure the extent to which participants felt their relatedness or bonding needs were satisfied, with seven items rated on a 7-point Likert scale (1 = ‘not at all true’ to 7 = ‘very true’). Examples of items included ‘I get along with people I come into contact with’ and ‘I really like the people I interact with.’ Higher scores on the subscale represent a higher level of relatedness needs satisfaction or sense of relatedness. Previous studies have confirmed the good reliability and validity of this subscale (Liu et al., 2013).

The trauma film paradigm (TFP; Holmes et al., 2004) was used to induce a traumatic experience. This is a well-established paradigm of traumatic experience arousal. Participants were shown a film related to a traumatic event, with the assumption that exposure to a traumatic film induces symptoms similar to those observed in an actual trauma event, including negative emotions and intrusive memories of the trauma experienced (James et al., 2016). The trauma group and control group, respectively, watched the videos, ‘Wenchuan Earthquake’ or ‘Weather Forecast’ for seven minutes.

Prosociality was assessed using a multi-round charitable donation task, following Varma and Hu (2022). Participants accepted or rejected each possible allocation decision, and had to make decisions in each of 16 rounds to ensure stable measurements. Prosociality was indicated by the mean amount of money each participant decided to donate in the task, which was treated as a continuous variable. First, a descriptive introduction to a donation case from Tencent Public Welfare was presented, and then participants were asked to make an allocation decision by pressing a button. There were 16 trials for each task; that is, 16 donation schemes were presented. Participants had a fictional amount of 30 RMB (the total amount of participant award), a part of which they could keep or donate in each trial. Participants chose to accept or reject the schemes by pressing the key on the keyboard (see Figure 2). They were told that their decision in the task was related to their final award. To reduce the risk of participants guessing the intention of the experiment, distraction tasks that also used keystroke responses were included.

Figure 2. Multi-round charitable donation task.

3.1.3. Procedure

In this between-subjects design, participants were randomly divided into the trauma group (n = 23) or the control group (n = 20), with all participants providing their informed consent. Prosociality was examined as a moderator that influenced the impact of the two groups on the dependent variables. These variables were sense of competence, sense of relatedness, search for meaning, and sense of meaningfulness.

First, participants in both groups were shown peaceful pictures to generate calmness. Then, they watched a video to induce a traumatic experience (trauma group) or neutral emotions (control group). They completed the PANAS as a manipulation check. Next, a multi-round charitable donation task was used to measure the degree of prosociality. Finally, participants completed the measures of sense of competence and relatedness, search for meaning, and sense of meaningfulness. The procedure for each group was the same, as shown in Figure 3. After the experiment, participants filled in a donation commitment form. We deducted the average amount of money donated by each participant in the donation task from their participant award (30 RMB). Additionally, we interviewed the participants to assess their emotional state and ensure that they were no longer disturbed by the trauma film.

Figure 3. Experimental process in Study 2.

Note. PANAS = Positive and Negative Affect Schedule. MLQ = Meaning in Life Questionnaire.

3.2. Results

An independent samples t-test showed that the trauma group’s negative affect (M = 1.79, SD = 0.61) was significantly higher than that of the control group (M = 1.30, SD = 0.31), t(34) = 3.34, p = .002, d = 1.15. There was no significant difference in positive affect between the trauma group (M = 1.70, SD = 0.45) and control group (M = 1.82, SD = 0.75), t(41) = −0.62, p = .54. This suggests that the TFP was effective in evoking the trauma experience in the trauma group.

Next, the moderating effect analysis was conducted using PROCESS in SPSS version 26.0 (Hayes, 2017). In this analysis, the trauma group was treated as the independent variable, while prosociality was examined as a potential moderator influencing the effects of trauma on sense of competence and relatedness, search for meaning, and sense of meaningfulness. Simple slope analysis was used to further analyse the moderating effect of prosociality on the negative effect of trauma. We divided the participants into high and low groups according to their prosociality (high prosocial group = M + 1SD; low prosocial group = M – 1SD; e.g. Aiken & West, 1991), and then compared the impact of trauma on the dependent variables at these two prosociality levels.

For sense of competence, the moderation model was nonsignificant, F(3,39) = 0.20, p = .90. The main effect of trauma was nonsignificant, b = 0.08, p = .81; the main effect of prosociality was nonsignificant, b = 0.03, p = .90; and the interaction effect between trauma and prosociality was nonsignificant, b = −0.19, p = .55. This suggests that trauma exposure, prosociality, and the interaction of the two did not significantly affect a sense of competence. Thus, the damage of trauma to a sense of competence in Study 1 was not replicated.

For sense of relatedness, the moderation model was marginally significant, F(3,39) = 2.41, p = .08, η_p²= 0.16. The main effect of trauma was marginally significant, b = 0.52, p = .09; the main effect of prosociality was nonsignificant, b = 0.02, p = .91; and the interaction effect of trauma and prosociality was nonsignificant, b = −0.44, p = .12. This suggests that exposure to traumatic events evoked a marginally significant sense of relatedness for individuals, while prosociality, or the interaction of trauma and prosociality, did not significantly impact their sense of relatedness.

For search for meaning, the moderation model was significant, F(3,39) = 3.94, p = .02, η_p²= 0.23. Neither the main effect of trauma (b = 0.42, p = .11) nor the main effect of prosociality was significant, b = −0.04, p = .84; but the interaction effect between trauma and prosociality was significant, b = −0.48, p = .05. Further simple slope analysis showed that for participants with low levels of prosociality, trauma significantly positively predicted search for meaning, simple slope = 0.88, p = .02; for participants with high levels of prosociality, trauma had a nonsignificant negative predictive effect on search for meaning, simple slope = −0.15, p = .68, as shown in Figure 4. The findings suggest that prosociality moderated the relationship between trauma and the search for meaning. Specifically, for participants exhibiting low levels of prosociality, simulated trauma triggered a heightened search for meaning.

Figure 4. Results of simple slope analysis in Study 2.

For sense of meaningfulness, the moderation model was nonsignificant, F(3,39) = 1.73, p = .18. Specifically, the main effect of trauma was marginally significant, b = −0.53, p = .06; the main effect of prosociality was not significant, b = 0.09, p = .65; and the effect of the interaction between trauma and prosociality was nonsignificant, b = −0.25, p = .35. This implies that exposure to trauma events threatened individuals’ sense of meaningfulness, but prosociality was not helpful for enhancing meaningfulness in the face of trauma. This finding did not support the results of Study 1.

3.3. Discussion

The TFP adopted in Study 2 effectively induced participants’ traumatic experience. Compared with the control group, the trauma group reported a lower sense of meaningfulness, which is consistent with the concept of Shattered Assumptions (Janoff-Bulman, 1989). Unlike our hypothesis, the trauma group’s sense of relatedness was marginally significantly higher than that of the control group, indicating that the experience of trauma satisfied the need for relatedness. Perhaps the trauma video that we chose in this study may account for the result. The Wenchuan earthquake on 12 May 2008 was the worst collective natural disaster in China in decades, in which more than 80,000 people died or remain missing; it generated a direct economic loss of about 845 billion yuan (Wang & Wang, 2023). The whole nation united and showed unprecedented solidarity when facing the devastating disaster (Xu, 2009). We speculated that the video of the Wenchuan earthquake activated not only the trauma experience but also the memory or experience of unity or solidarity, which enhanced the sense of bonding. Therefore, a ceiling effect may have occurred, and the promoting effect of prosocial behaviour on the sense of relatedness did not manifest as we expected. Whether this result can be generalized to other collective traumas, and how it would apply to individual traumas, needs further examination.

The current study found that prosociality can moderate the relationship between trauma and meaning seeking, but it does not moderate the impact of trauma on a sense of competence or meaningfulness. Interestingly, we also found that after experiencing the catastrophic disaster, individuals with low prosociality reported greater intention to search for meaning, whereas for high-prosociality individuals the search for meaning was the same in both the trauma and the control groups. This implies that prosociality may act as a coping mechanism, associated with mitigating the effects of trauma, potentially by preventing an increase in meaning seeking.

The findings were inconsistent with the results of Study 1, in which prosocial behaviour moderated the negative impact of trauma on the sense of competence and meaningfulness, with a small to medium effect size. In Study 2, the moderating effect of prosociality on trauma consequences was mainly reflected in meaning seeking, with large effect sizes. This may be attributed to differences in the methods used to induce trauma arousal. The autobiographical recall paradigm used in Study 1 induces personally experienced trauma. Thus, the type of trauma participants recalled was unclear – it could be collective or individual trauma, human-caused or natural disaster – nor was it specified how much time had passed since the trauma had been experienced. The challenge posed by these traumatic events exceeded the participants’ coping capabilities, thereby threatening their competence. The trauma film paradigm used in Study 2, by contrast, evokes natural disasters that are experienced collectively. Compared with individual trauma, collective trauma is more likely to stimulate collective strength; if the trauma is human-caused, it is more likely to destroy expectations of one’s abilities, resulting in a sense of incompetence (Muldoon et al., 2019). Therefore, while Study 1 reflected a moderating effect on sense of competence, the moderating role of prosocial behaviour between trauma and sense of competence was nonsignificant in Study 2.

Understanding and finding meaning can be an important part of the process of coping with trauma and adapting to the post-traumatic environment. This process can be divided into two sequential stages: searching for meaning and finding meaning. These two stages show differences in emotional experience, degree of pain, and adaptability (Silver & Updegraff, 2013). From a temporal perspective, individuals who experience trauma will search for meaning first, then find the meaning. Notably, not all meaning-seeking processes result in meaning found. Therefore, in Study 2, evoking a temporary traumatic experience externally was more likely to stimulate meaning seeking than finding meaning. In Study 1, recalling a personal traumatic event, in which the participants might have finished the process of searching for meaning and found meaning in the trauma, instead evoked a sense of meaningfulness. Moreover, the experimental paradigms in Study 1 and Study 2 were conducted in a controlled laboratory environment, potentially limiting the extent of the observed effects of trauma and ecological validity.

4. Study 3

Study 1 and Study 2 provided partial evidence that prosocial behaviours could, potentially, effectively alleviate the adverse impacts of trauma. In Study 3, we examined the potential effectiveness of a prosocial-themed intervention aimed at reducing PTSD, addressing the search for meaning, enhancing the sense of competence, relatedness, and meaningfulness, and facilitating PTG.

4.1. Methods

4.1.1. Participants

A survey assessing post-traumatic symptoms was distributed online to 254 undergraduate students at several universities in Zhejiang Province (China). Participants who scored in the top 50% on the PTSD measure were invited to partake in Study 3. On the premise of respecting participants’ willingness, 20 participants with traumatic experiences and a high degree of PTSD were finally involved. In the recruitment advertisement, we informed the potential participants that there would be three assessments: at the beginning of the intervention programme (T1), at the end of the intervention (T2), and at a follow-up 1 month after the intervention (T3). After confirming their participation, a one-to-one interview was conducted with each person to collect their demographic information and reconfirm their participation intention. Participants were randomly divided into two groups: the intervention group (n = 11; 5 male and 6 female; M_age= 21.18, SD_age= 1.89) and the waitlist control group (n = 9; 3 male and 6 female; M_age = 20.33, SD_age= 1.50).

4.1.2. Experimental materials

The Competence Needs and Relatedness Needs Subscales of BPNS, and the MLQ (see Methods in Studies 1 and 2) were used in Study 3. Given that all participants in Study 3 had experienced trauma, measures of PTSD and PTG were incorporated to directly examine the effects of the intervention.

PTSD. The self-report PTSD Checklist was compiled by Weathers et al. (2013) and was based on the DSM-5 criteria. The present study used the Chinese version of the scale revised by Zhou et al. (2017) to measure participants’ post-traumatic stress symptoms, with 20 items rated on a 5-point Likert scale (1 = ‘not at all’ to 5 = ‘extremely’). Examples of items included, ‘Repeated, disturbing, and unwanted memories of the traumatic events’ and ‘Avoiding memories, thoughts, or feelings related to the traumatic event.’ As the score increased, the post-traumatic stress symptoms became more severe. This scale demonstrated high reliability in this study, with α coefficients of 0.88 at T1, 0.93 at T2, and 0.93 at T3.

PTG. The Post-traumatic Growth Inventory was compiled by Tedeschi and Calhoun (1996) and the Chinese version was revised by Zhou et al. (2014) to measure PTG. It comprises 22 items across three subscales: Perceived Changes in Self (e.g. ‘I discovered that I'm stronger than I thought I was’; ‘I’m able to do better things with my life'), Changed Sense of Relationships with Others (e.g. ‘Knowing that I can count on people in times of trouble’; ‘A sense of closeness with others’), and Changed Philosophy of Life (e.g. ‘My priorities about what is important in life’; ‘An appreciation for the value of my own life’). The items were rated on a 6-point Likert scale (1 = ‘no change’ to 6 = ‘very great degree of change’). An increase in scores of subscales indicated that more positive changes occurred in each dimension of post-traumatic growth. In current study, this scale showed high reliability at T1 (α = 0.94), T2 (α = 0.94) and T3 (α = 0.94).

4.1.3. Procedure

A randomized controlled trial (RCT) design was adopted, with group (intervention or waitlist control) as the independent variable, and sense of competence and relatedness, search for meaning, sense of meaningfulness, PTSD, and PTG (and its subscales – perceived changes in self, changed sense of relationships with others, and changed philosophy of life) as dependent variables.

The intervention group agreed to complete 2-hour face-to-face interventions each week for 4 weeks. The intervention involved group activities with prosociality as the theme. The waitlist control group received no intervention at all. Both groups were assessed when the intervention started (pre-test), when the intervention ended (post-test), and 1 month after the intervention (follow-up). The steps of the intervention are illustrated in Figure 5.

Figure 5. Experimental process in Study 3.

Pre-test (T1): Participants were required to sign the informed consent form and fill out all the questionnaires.

Intervention: The intervention group participated in a prosocial-themed group intervention for about two hours per week in a month. The intervention was led by a doctoral student in clinical and counselling psychology under the guidance of an experienced psychological counsellor. The intervention incorporated themes such as an introduction to prosocial behaviour, value identification, best self, and other topics related to prosocial behaviours (Table 2).

Table 2. Activity programme for prosocial-themed group intervention in Study 3.

Name	Purpose	Content
Preliminary acquaintance	Group members get to know each other, formulate group commitment, and get an initial understanding of prosocial behaviour	Face-to-face introduction, group rule-building, introduction to prosocial behaviour, assignment of prosocial homework
My Values	Explore and further understand participants’ existing values, and guide by prosocial values	Identity warm-up, value debate, sharing of prosocial behaviour experience, assignment of prosocial homework
Mutual assistance	Express participants’ own needs and dilemmas, and promote mutual assistance	Positive non-verbal communication, experience sharing and member support, sharing of prosocial behaviour experience, assignment of prosocial homework
Farewell	Learn how to listen and praise others, end of the group, and farewells	Learn to listen and praise, share prosocial behaviour experiences, end, and farewells

Post-test (T2): At the end of the intervention, both groups completed the same questionnaires used in pre-test. Then, one-to-one interviews were conducted with participants in the intervention group to gather their feedback.

Follow-up (T3): One month after the intervention finished, participants in both groups completed all the questionnaires once more.

4.1.4. Data analysis

We followed the data analysis methods used by Zang et al. (2013) for RCTs with small sample. Analyses of covariance (ANCOVAs), serving as a reliable statistical strategy for assessing the results of RCTs (Vickers, 2005; Zang et al., 2013), were used to compare main dependent variables between the two groups at T2 or T3, after controlling for corresponding variables at T1. Paired t-tests were used to analyse T1 vs. T2, and T1 vs. T3 within each group. Hedge’s g was reported as the effect size of within-group variations, and η_p² was reported as the effect size of between-group variations.

4.2. Results

Tables 3 and 4 present the M and SD of each dependent variable at each time point (T1, T2, and T3) in the intervention group and the waitlist control group. As expected, given the randomized assignment to groups, there were no significant group differences (ps > .05) for any variables at baseline (T1). Table 3 presents the difference in test values and effect sizes within and between groups, before and after the intervention. Owing to the small sample size, the statistical significance may not meaningful; the results are reported and discussed mainly in terms of effect size. Statistical significance is also presented for reference in Tables 3 and 4.

Table 3. Analysis of differences between pre-test (T1) and post-test (T2) in Study 3.

Variable	Group	M(SD)		Mean Difference (T2–T1)	Within-group			Between-group (T2)
		T1	T2		t	p	Hedge's g	F	p	ηp^2
Sense of Competence	Intervention Group	4.47 (1.16)	4.52 (1.15)	0.05	0.16	.88	0.05	0.23	.64	0.01
	Control Group	4.33 (0.82)	4.57 (0.80)	0.24	1.51	.17	0.55
Sense of Relatedness	Intervention Group	4.49 (1.08)	4.68 (1.00)	0.18	0.70	.50	0.23	0.04	.84	0.00
	Control Group	4.89 (0.65)	4.86 (0.51)	–0.03	–0.23	.82	–0.09
Search for Meaning	Intervention Group	4.82 (0.66)	4.57 (1.34)	–0.25	–0.72	.49	–0.24	0.77	.39	0.04
	Control Group	5.39 (1.48)	4.56 (1.43)	–0.83	–2.37	.05	–0.87
Sense of Meaningfulness	Intervention Group	4.11 (1.46)	4.64 (1.68)	0.53	1.46	.17	0.47	0.68	.42	0.04
	Control Group	4.56 (1.32)	4.47 (0.87)	–0.09	0.20	.85	–0.08
PTSD	Intervention Group	3.35 (0.92)	2.71 (0.89)	–0.64	3.52	.01	–1.14	1.44	.25	0.08
	Control Group	3.13 (0.32)	2.85 (0.67)	–0.28	1.58	.15	–0.58
PTG	Intervention Group	3.67 (1.38)	3.93 (1.24)	0.27	2.12	.06	0.69	4.19	.60	0.20
	Control Group	3.91 (0.60)	3.77 (0.85)	–0.15	–1.03	.33	–0.37
Perceived Changes in Self	Intervention Group	3.66 (1.45)	4.04 (1.32)	0.38	2.44	.04	0.80	4.86	.40	0.22
	Control Group	3.89 (0.66)	3.74 (0.71)	–0.15	–0.87	.41	–0.32
Changed Sense of Relationships with Others	Intervention Group	3.70 (1.29)	4.05 (1.33)	0.35	1.52	.16	0.50	4.72	.40	0.22
	Control Group	4.16 (0.70)	3.81 (0.88)	–0.35	–2.38	.05	–0.87
Changed Philosophy of Life	Intervention Group	3.64 (1.74)	3.64 (1.42)	0.00	0.00	1.00	0.00	0.08	.79	0.01
	Control Group	3.67 (0.75)	3.76 (1.24)	0.09	0.31	.77	0.11

Note: PTSD = Post-traumatic stress disorder. PTG = Post-traumatic growth.

Table 4. Analysis of pre-test (T1) and follow-up (T3) difference test in Study 3.

Variable	Group	T3 M (SD)	Mean Difference (T3–T1)	Within-group			Between-group (T3)
				t	p	Hedge's g	F	p	ηp^2
Sense of Competence	Intervention Group	4.55 (1.17)	0.08	0.29	.78	0.10	0.27	.61	0.02
	Control Group	4.24 (1.03)	–0.09	–0.24	.81	–0.09
Sense of Relatedness	Intervention Group	4.86 (0.91)	0.36	1.57	.15	0.51	0.87	.36	0.05
	Control Group	4.81 (0.66)	–0.08	–0.35	.74	–0.13
Search for Meaning	Intervention Group	4.73 (1.53)	–0.09	–0.21	.84	–0.06	1.65	.22	0.09
	Control Group	4.36 (1.32)	–1.03	–2.92	.02	–1.06
Sense of Meaningfulness	Intervention Group	4.69 (1.74)	0.58	1.47	.17	0.47	3.93	.60	0.19
	Control Group	3.80 (1.32)	–0.76	–1.60	.15	–0.58
PTSD	Intervention Group	2.67 (0.93)	–0.68	–3.09	.01	–1.00	0.50	.49	0.03
	Control Group	2.76 (0.80)	–0.38	–1.47	.18	–0.54
PTG	Intervention Group	3.69 (1.55)	0.03	0.15	.89	0.04	2.62	.12	0.13
	Control Group	3.45 (0.62)	–0.46	–1.95	.09	–0.71
Perceived Changes in Self	Intervention Group	3.79 (1.69)	0.13	0.55	.59	0.18	2.35	.14	0.12
	Control Group	3.47 (0.55)	–0.42	–1.79	.11	–0.66
Changed Sense of Relationships with Others	Intervention Group	3.74 (1.56)	0.04	0.20	.84	0.06	2.48	.13	0.13
	Control Group	3.63 (0.73)	–0.52	–1.89	.09	–0.69
Changed Philosophy of Life	Intervention Group	3.48 (1.77)	–0.15	–0.69	.50	–0.23	0.57	.46	0.03
	Control Group	3.22 (0.93)	–0.44	–1.36	.21	–0.49

Note: PTSD = Post-traumatic stress disorder. PTG = Post-traumatic growth.

Between-group comparisons showed that when the corresponding variables at pre-test (T1) were controlled, post-test (T2) differences between the two groups in PTG, perceived changes in self, and changed sense of relationships with others were significant or marginally significant, with large effect sizes (η_p² = 0.20 ∼ 0.22); group differences in PTSD had medium effect sizes (η_p² = 0.08).

After controlling for the corresponding variable at T1, the difference in sense of meaningfulness at T3 between the intervention group and control group showed a large effect size (η_p² = 0.19). There were medium effect sizes between the two groups in search for meaning, PTG, perceived changes in self, and changed sense of relationships with others at T3 (η_p² = 0.09 ∼ 0.13).

To reflect the changes more intuitively in both the intervention group and the control group, Figure 6 presents the average changes over time in search for meaning, sense of meaning, PTSD, PTG, perceived changes in self, and changed sense of relationships with others. Given the numerous results pertaining to within-group differences, see Tables 3 and 4 for more detailed information.

Figure 6. Changes over time in (a) Search for meaning, (b) Sense of meaningfulness, (c) PTSD, (d) PTG, (e) Perceived changes in self, and (f) Changed sense of relationships with others in both groups in Study 3.

Note: PTSD = Post-traumatic stress disorder. PTG = Post-traumatic growth.

4.3. Discussion

A prosocial-themed group intervention was conducted in Study 3 among victims of trauma with high-level PTSD. Pre-test results showed no heterogeneity between the intervention group and the control group. In terms of effect size results, the increase in PTG and decrease in PTSD in the prosocial-themed intervention group were larger than those in the control group. One month after the intervention, an increase in PTG was observed, particularly in positive change in self and relationships with others, with medium effect sizes in the intervention group compared with the control group. This study showed that the prosocial-themed intervention can produce short-term alleviation of PTSD, and the promoting effect on PTG can persist even a month later, thus exerting a long-term impact. On the one hand, engaging in prosocial behaviours may enable victims to temporarily divert their attention from the pain and intrusive memories induced by traumatic events to the needs of others (Steen, 2006; Vollhardt & Staub, 2011). Therefore, while this approach may alleviate the negative effects of trauma in the short term, it may also lead victims to overly focus on the needs of others, and thereby avoid thoughts and feelings related to their trauma. This may prevent them from thinking about or dealing with problematic situations, which can easily increase avoidance symptoms (Woodward et al., 2020), making it difficult to maintain relief from PTSD over a long period. On the other hand, helping others encourages victims to discover their own potential strength, and it also makes it easier for them to depend on and trust others, which can increase positive interactions with others (Tedeschi & Calhoun, 1996, 2004) and thereby promote PTG. Moreover, this positive change tends to persist over time and is genuine and stable. Interestingly, one month after the intervention, there was still a medium effect size observed in its enhancing effect on meaning, particularly in the search for meaning and sense of meaningfulness. The reason for the delayed effect of a sense of meaning might be that the process of extracting meaning from traumatic events is complex and requires time; victims may be in a stage of searching for meaning long after the traumatic event. Engaging in prosocial behaviours can help them find meaning sooner and more effectively; they gradually adapt to genuine contact and interaction with others, feel higher personal value in the process of helping, establish social connections with others, and gain social recognition and goodwill (Klein, 2017). This may result in increased cognitive reappraisal, and thus in their reconstruction of positive patterns in themselves and others (Sharp et al., 2012). These positive experiences accumulate over time and may prompt victims to perceive meaning in life and, eventually, to be more willing to seek other meanings in life (Janoff-Bulman, 1989). These findings hint at the possibility that prosocial-themed interventions could enhance PTG, facilitate finding meaning in life, and mitigate PTSD. However, more comprehensive studies are warranted to fully confirm its implications and long-term effects.

5. General discussion

How can pain be turned into strength? The results from our three experiments tentatively suggest an association between prosocial behaviours and enhanced coping mechanisms for trauma victims. After experiencing trauma, individuals’ prosocial behaviour increases their sense of competence and meaningfulness (Study 1), while reducing their search for meaning (Study 2). Compared with the control group, the intervention group in Study 3 showed that prosocial intervention could promptly reduce PTSD, facilitate PTG, increase the sense of meaningfulness, and prevent a decrease in meaning seeking one month after the intervention (with medium to large effect sizes).

Induced traumatic experiences have negative effects, such as triggering negative emotions, impairing a sense of competence and meaningfulness, thus leading to a search for meaning. This is consistent with the concept of Shattered Assumptions (Janoff-Bulman, 1989). Traumatic experiences destroy victims’ original assumptions about the world and self, leading to a sense of meaninglessness and insecurity, as well as doubts about self-worth, which reduces their sense of competence.

Study 1 found that prosocial behaviour may mitigate the impact of trauma on a person’s sense of competence. We observed that individuals who did not donate to charity exhibited a lower sense of competence after recalling a trauma experience, whereas those who donated did not show such decline. However, Studies 2 and 3 did not replicate these results. The difference between Studies 1 and 2 was the trauma induction paradigms used. In Study 1, the autobiographical recall paradigm focused on personally experienced trauma, whereas Study 2 used the trauma film paradigm, which evokes collectively experienced natural disasters. These paradigms may differ in their impact on individuals’ competence (see the discussion section of Study 2 for more details). Both Studies 1 and 3 involved personally experienced traumatic events, but in Study 3, both groups consisted of trauma victims with high levels of PTSD, which may have produced a floor effect in that the sense of competence was low for both groups. The enhancing effect of prosocial behaviour on competence may be effective for individuals with lower levels of PTSD or without PTSD. For those with high levels of PTSD, short-term prosocial behaviour may be less likely to improve a sense of competence.

Trauma decreased participants’ sense of meaningfulness and increased meaning seeking, a pattern that was more obvious in low prosocial individuals; no differences were detected in high prosocial individuals. The Shattered Assumptions concept asserts that trauma disrupts one’s fundamental assumptions, forcing the victim to face what they may perceive as a meaningless world in which disorder, uncontrollability, insecurity, and random disasters occur (Janoff-Bulman, 1989). This sense of meaninglessness can lead to feelings of depression, distress, and fear, thus driving the victim to actively search for and reestablish meaning (Park & George, 2013; Xu, 2018). Prosocial behaviours can build connections with others and help the victim realize their importance and worth. This is an important way to find meaning and rebuild positive beliefs about the world (Janoff-Bulman, 1989).

The impact of prosocial behaviour on meaning after trauma was reflected in a sense of meaningfulness in Study 1, in meaning seeking in Study 2, and in both in Study 3 (with a delayed effect). Because an autobiographical recall paradigm (i.e. participants are asked to recall a personal traumatic event) was used in Study 1, participants may have completed a search for meaning and found the meaning of their trauma, thereby eliciting a sense of meaningfulness. The trauma film paradigm used in Study 2, by contrast, evoked a temporary traumatic experience externally; for traumatic events that participants have not experienced, the immediate reaction is meaning seeking. In Study 3, victims with high levels of PTSD may have been continuously searching for positive meaning brought about by their traumatic experiences. After participating in prosocial interventions, they had formed many positive experiences and beliefs, which may have prompted them to perceive meaning in life and to be willing to seek more meaning after a period of time (Janoff-Bulman, 1989), thus indicating a delayed emergence of the intervention’s effect on meaning.

Notably, on the basis of the findings of Study 1 and Study 2, Study 3 marks the first development and testing of a prosocial-themed group intervention for trauma victims. This intervention, with victims of trauma who have high PTSD, increased the ecological validity of our findings. It also has the potential to promptly alleviate PTSD and enhance PTG, and over time, possibly elevate individuals’ sense of meaning while preventing a decrease in meaning seeking, as suggested by the medium to large effect sizes observed in Study 3. After the intervention, some participants mentioned in interviews, ‘I stopped thinking about the trauma, and I’m just living with a positive attitude to life' or ‘Knowing how to deal with trauma, this intervention gave me a new understanding about the trauma.’ The prosocial-themed intervention thus relieved pain and reduced negative perceptions of trauma. Prosocial behaviours, moreover, helped them achieve PTG, explore more deeply both self and interpersonal meaning (Joseph & Linley, 2008), and regain a sense of meaning and worth. Participants also mentioned changes in self-experience: ‘I found that I can provide some help to others in some aspects, so I have a sense of accomplishment’ or ‘Others may need me more than I thought.’ Positive experiences such as accomplishment and worth increased. Participants gradually established good connections with others and actively participated in social activities: ‘Maybe it is not difficult to connect with others.’ Victims’ prosocial behaviours led them to seek the welfare of others, find meaning, and rebuild competence.

This study had some limitations. First, due to differences between the trauma induction paradigms and the prosocial behaviour measurement paradigms, the findings of Study 2 could not replicate those of Study 1. Future research should improve the study paradigms to further validate the results, and thereby test the stability of the findings. Furthermore, the participants in Study 3 were trauma victims who reported high levels of PTSD, whereas those in Studies 1 and 2 were from a non-clinical population. These differences in sample characteristics may have contributed to the observed inconsistencies between the findings of Study 3 and those of Studies 1 and 2. Second, in both Study 1 and Study 2, monetary donation tasks were used to measure prosocial behaviour; this is only one type of prosocial behaviour. Therefore, future research should measure prosocial behaviour by, for example, time donation and cooperative behaviour. Third, participants were mainly college students, meaning that both their age range and life experiences were restricted. Our findings require verification among people who represent a wider age range and more types of traumatic events. Fourth, because of the small sample size, especially in Study 3, the results did not reach statistical significance. Therefore, we added effect size as the main statistical result. In future work, the sample diversity should be expanded and the sample size increased to ensure that the findings can be validated. Fifth, some of our findings exhibited marginal significance, thus requiring greater caution in interpreting and generalizing these results. In the future, other potential boundary conditions should be explored to enhance the stability and effects of the research findings.

Despite these limitations, the current study has important theoretical and practical implications. For theoretical implications, this research combined experiments and an RCT to provide multi-method evidence that prosocial behaviour, as a trauma coping strategy, can enhance self-cognition and a sense of meaning. Furthermore, the diversity in the findings may stem from inconsistencies in the paradigms used (i.e. trauma induction paradigm and prosocial behaviour measurement paradigm) or from differences in the samples (i.e. varying levels of post-traumatic stress symptoms) across three studies. While these results may seem contradictory, they provide a broader perspective of the issue at hand. They suggest that the effectiveness of prosocial behaviour as a coping mechanism may vary depending on the type or severity of trauma, or the form of prosocial behaviour. This, in turn, sparks further research and discussion in the fields of trauma and prosociality. In terms of practical implications, to our knowledge, this is the first study to test a prosocial-themed intervention programme for victims of trauma. The intervention was effective in alleviating PTSD, and promoting the reconstruction of meaning and PTG. This finding validates and extends Midlarsky’s (1991) view and its applicability in traumatic events. The findings provide new ideas for incorporating prosocial behaviours into intervention programmes to help victims cope with trauma and turn pain into strength.

Acknowledgements

Thanks to Jia Chen for providing assistance in data collection.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by the Ministry of Education Humanities and Social Sciences Research Youth Fund Project of China [grant number 19YJCZH204].