The Co-occurrence of Self-Harm and Aggression: A Cognitive-Emotional Model of Dual-Harm

Abstract

There is growing evidence that some individuals engage in both self-harm and aggression during the course of their lifetime. The co-occurrence of self-harm and aggression is termed dual-harm. Individuals who engage in dual-harm may represent a high-risk group with unique characteristics and pattern of harmful behaviours. Nevertheless, there is an absence of clinical guidelines for the treatment and prevention of dual-harm and a lack of agreed theoretical framework that accounts for why people may engage in this behaviour. The present work aimed to address this gap in the literature by providing a narrative review of previous research of self-harm, aggression and dual-harm, and through doing so, presenting an evidence-based theory of dual-harm - the cognitive-emotional model of dual-harm. This model draws from previous studies and theories, including the General Aggression Model, diathesis-stress models and emotional dysregulation theories. The cognitive-emotional model highlights the potential distal, proximal and feedback processes of dual-harm, the role of personality style and the possible emotional regulation and interpersonal functions of this behaviour. In line with our theory, various clinical and research implications for dual-harm are suggested, including hypotheses to be tested by future studies.

Keywords: Suicide; aggression; assault; co-occurrence; dual-harm; self-harm; self-injury; violence.

FIGURE 1

Experiential avoidance theory of self-harm. This figure provides a simplified illustration of the experiential avoidance theory of self-harm. As highlighted, deficits in emotional regulation may contribute to an individual using experiential avoidance as a response to distressing emotional experiences. Here, experiential avoidance refers to attempts to avoid distressing emotions, even when such attempts may cause harm to the individual. According to the theory, the individual may use self-harm as an experiential avoidance strategy to escape from or avoid their unwanted emotions. Self-harm may provide the individual with temporary relief from their emotional distress, thus leading to negative reinforcement of their self-harm. This negative reinforcement feeds back into the person’s emotional regulation deficits, thus repeating the cycle of experimental avoidance and maintaining the use of self-harm.

FIGURE 2

General Aggression Model. This figure highlights the proximal process of aggression in the General Aggression Model. The proximal process occurs in three stages: Inputs, routes, and outcomes. First, in the input stage, person-related factors and situations act as inputs which, in the routes stage, activate certain emotions, cognitions and arousals in the individual. The person’s internal state then affects appraisal and decision-making processes in the outcome stage, leading to them engaging in either a thoughtful action or impulsive action, such as aggression. This behavioural outcome impacts the individual’s social encounter and feeds back into person and situation related factors through learning mechanisms, thus perpetuating the model’s process.

FIGURE 3

Potential distinct profile of dual-harm. This Venn diagram highlights the potential mechanisms that may distinguish dual-harm as a separate clinical entity from the behaviours of self-harm alone and aggression alone. According to previous research, compared to those who engage in sole-harmful behaviours, individuals who have a history of dual-harm are significantly more likely to engage in a higher frequency of harmful behaviours, as well as a wider range and more severe methods of risky behaviours. Furthermore, these individuals have been found to have higher levels of personal and contextual risk-factors. Such higher levels of risk in those who dual-harm may be an important factor that distinguishes dual-harm from the sole-harm behaviours of self-harm and aggression.

FIGURE 4

The cognitive-emotional model of dual-harm. This figure illustrates the cognitive-emotional model of dual-harm. Here, the causal pathways to dual-harm are divided into two main processes: distal and proximal. In the distal processes, biological and environmental factors combine to develop a certain personality style. Through its effects on cognition, arousal and affect, this personality style facilitates the proximal processes of dual-harm by predisposing the individual to harmful behaviours. In the proximal processes, the social context/situation the individual is in and their expectancies of harmful behaviours influences the function of their dual-harm behaviour (i.e., emotion regulation or interpersonal motivation), as well as the specific harmful behaviour that they choose to engage in (i.e., self-harm or aggression). Specifically, the individual may choose to engage in dual-harm as an emotional regulation response to their distressing negative emotions. Alternatively, they may choose to engage in dual-harm to fulfil an interpersonal function. Finally, the outcome behaviour affects the environmental response and individual’s experience. Through learning processes, this response may reinforce the individual’s maladaptive schemas and feed back into their personality traits and expectancies, thereby repeating the process of dual-harm.