The results of this program of research also provide the foundations for future work which could have important clinical implications, particularly for the treatment and prevention of PTSD, as well as the treatment of self- harmers.
7.6.1 Thought Suppression, ABM Retrieval and PTSD
One of the key findings of this program of research was that thought suppression was a better predictor of enhanced negative ABM retrieval and reduced personal semantic memory retrieval than symptoms of depression and PTSD (Chapters 3 & 6). The retrieval of ABMs is crucial to shaping and maintaining the concept of the self, and as such recalling and processing ABMs forms an important part of all talk-based psychotherapies. If thought suppression, like rumination, is at least in part responsible for producing some of the ABM patterns observed in clinical populations, then addressing this coping style in therapies could aid in altering the cognitive symptoms of the disorders. A crucial future research study here should investigate whether altering coping mechanisms in high trait suppressors results in changes in ABM patterns. For instance, if high suppressors are encouraged to only suppress a thought or memory in situations when they cannot address them, but to address the issues as soon as the time to do so is appropriate, this may
break the cycle of perpetual suppression in order to cope with an unwanted thought or memory. In therapy, high suppressors could be encouraged to note any thought or memories they are actively suppressing, and to raise these thoughts during their next therapy session in order to process them. These thoughts, in return, may become less intrusive in the future and therefore reduce the need to suppress them. If this is the case, then this coping mechanism could be addressed in therapeutic settings in order to alter ABM retrieval patterns in patients.
A second potential clinical implication concerns the prevention of PTSD in high-risk groups. The research presented in Chapter 4 demonstrated that inducing thought suppression in a normal student group directly resulted in the faster retrieval of negative episodic ABMs, as well as reduced personal semantic memory retrieval; which are recall patterns also observed in
individuals suffering from PTSD. Therefore, it is possible that a suppressive coping style may be one of the factors that influence whether or not an individual develops the cognitive symptoms of PTSD following the exposure of a traumatic event. A large-scale longitudinal study would be needed in order to test this hypothesis; however, the potential benefits of the results are considerable. If it is found that individuals with a higher tendency to engage in thought suppression are more likely to develop some of the cognitive
symptoms of PTSD, then individuals at high risk of trauma exposure, such as firemen, police officers and soldiers could be screened for levels of thought suppression and be instructed in the benefits of using other, approach based coping mechanisms instead before deployment.
7.6.2 Thought Suppression, ABM Retrieval and Self-Harm
A final clinical implication of this present program of research revolves around the role of thought suppression in the ABM patterns seen in individuals who self-harm. If the act of deliberate self-harm is a viewed as an avoidant coping mechanism in itself (Chapman, Gratz & Brown, 2006) then a possible model for explaining the inter-relationship between ABM retrieval, thought suppression and self-harm is that both thought suppression and self- harm may occur in order to cope with unwanted negative thoughts and memories. Seeing that childhood trauma is a common predecessor of deliberate self-harm, potential self-harmers often have extremely negative experiences in their pasts. The results of the present program of research suggest that self-harmers are high trait thought suppressors (Chapter 4), which implies that as an initial attempt to cope with these unwanted memories potential self-harmers may engage in thought suppression.
However, this engagement is likely to lead not only to the suppressed thought being more accessible (paradoxical effect of thought suppression), but also to increased retrieval of other negative memories and fewer personal semantic memories (Chapter 4). The increased negative memory retrieval would be a considerable strain on the working self. These negative memories would either have to be suppressed further, or become assimilated into the
autobiographical memory knowledge base, which requires the adjustment of the goals of the working self. The reduced personal semantic memory
retrieval may imply a less stable concept of the self, which is more vulnerable to changes. If thought suppression continues to fail, the individual may turn to other, more extreme coping mechanisms, such as self-harm. Self-harm may
become more acceptable to the Self-Memory System if the goals of the working self and the self-concept become too negatively biased. In short, the present theory holds that thought suppression may lead to ABM retrieval patterns that together with the failed suppression attempts may create a vicious loop in which deliberate self-harm becomes more likely. Naturally, more research is needed in order to evaluate this theoretical model of thought suppression, ABM retrieval and self-harm. However, if this is found to be the case then addressing a suppressive coping style in self-harmers in therapeutic settings could prove to be particularly effective in the treatment of self- harming behaviours.