Violent Behavior

• Violence is an intentional act of threatened, attempted, or actual physical and/or psychological harm against a nonconsenting individual.

• Physical violence encompasses punching, strangling, weapon use, stabbing, shooting, and implicit actions including threats, psychological intimidation, coercion, and attempts at bodily harm.

• To better explain causal pathways, most overviews of the psychology of violence categorise it into types—sexual, homicide, hate-related, terrorism—while others focus on motivations.

• The FBI's Behavioral Analysis Section classifies murder into four motivation-based categories.

• Reactive violence is emotionally driven, while instrumental violence is goal-oriented. Research reveals that single-violence offenders commit reactive violence.

• Yet, instrumental and reactive violence are not completely distinct, and different processes and mechanisms underlying them.

Neuropsychological and Developmental Factors

• Since Mary Shelley's 1818 Frankenstein, the "abnormal brain" or "bad biology" has intrigued the public and researchers.

• Criminology and psychology have traditionally used biological theories of crime and violence.

• As research advanced, Lombroso's "born criminal" idea was replaced.

• Forensic evolutionary psychology, genetics, neurotransmitter systems, and early neuropsychological impairments are covered.

Forensic Evolutionary Psychology and Violent Behavior

• Darwin's theory of evolution focused on species members' survival and reproduction.

• Evolutionary psychology explores how natural selection impacts our minds and behaviour.

  • It examines how generations of affective, behavioural, and cognitive factors have shaped human behaviour.

• Homicide Adaptation Theory (HAT) posits that humans have developed psychological adaptations for murder to solve time-period-specific adaptive challenges, such as self-defense against approaching death.

  • HAT suggests that killing another person provided evolutionary benefits that self-defense in the face of imminent death did not.

• Some ancestral situations where murder would have benefited include

  • eliminating a cost-inflicting intrasexual competition

  • obtaining rivals' reproductively relevant resources

  • obtaining fruitful partners

  • building and sustaining a reputation that deters exploitation, lowering rival costs

  • stopping conspecifics from exploiting, injuring, raping, or killing self, family, mates, and coalitional allies in the present and future

  • protecting territory, resources, shelter, and food from competition

  • removing non-related people that waste resources

  • removing genetic relatives who interfere with investment in other vehicles better able to transform resource investment into genetic fitness

Genetics, Neurotransmitters, and Violent Behavior

• Media has popularised the idea of a "born killer" and shown small links between specific genetic differences and antisocial and violent behaviour.

• Yet, most genetic influences on human behaviour are complicated and polygenic, resulting from multiple genes and environmental factors.

• Research has focused on genes that degrade neurotransmitters like dopamine, serotonin, and monoamine oxidase (MAOA).

• Dopamine is implicated in behavioural activation. It motivates through activating other neurotransmitters.

• Research have connected severe violent conduct to dopamine overproduction or activity.

• Suicide, mood and personality disorders, impulsive violence, and drinking have been linked to low serotonin levels.

• Monoamine oxidase (MAOA): An enzyme that breaks down serotonin, dopamine, and other neurotransmitters, has been related to impulsive and violent aggression.

• Caspi et al. (2002) observed that maltreated boys' MAOA was linked to hostility and violence.

• Jeffrey Gray (1981, 1987) postulated that the behavioural activation system (BAS) and the behavioural inhibition system (BIS) interact to control learning and behaviour (BIS).

• Fowles (1988) employed Gray's theoretical framework to explain violent behaviour, suggesting that underactivation of the BIS due to low serotonin and norepinephrine levels causes impulsive behaviour that raises the risk for antisocial and aggressive behaviour.

Early Childhood Factors and Neuropsychological Deficits

• Prenatal and postnatal problems have been related in studies to a later development of delinquency.

• A risk factor for delinquency and violent behaviour has been found as prenatal lead exposure.

• Lower levels of self-control have been associated to developmental deficits in the prefrontal cortex during early childhood.

• Baby temperament is also associated with externalising behaviour issues in middle childhood, as well as antisocial and violent behaviour later in life.

• Hunger in childhood has been linked to various developmental difficulties, including impulsivity and violent behaviour.

Affect, Cognition, and Violence

• Social cognitive psychology provides theoretical frameworks, such as Excitation Transfer Theory and Frustration-Aggression Hypothesis, for understanding how background qualities interact with the environment and influence violent behaviour.

Excitation Transfer, Frustration-Aggression, and Cognitive Neoassociation

• Berkowitz's frustration-aggression hypothesis studied the dual roles of emotion and cognition. It was proposed that aversive situations cause negative affect, leading to aggressive conduct.

• Later, Berkowitz's updated cognitive neoassociation model of aggressiveness proposed that negative emotion initially stimulates a fight-or-flight response, which is activated by a network of connected thoughts, feelings, and physiological reactions.

• In the second phase of the Cognitive Neoassociation and Excitation Transfer paradigm, which examines the roles of affect and cognitions in violent conduct, cognitive processes are engaged.

• Zillmann et al. (1972) theorised that physiological arousal from a previous scenario might be carried over to a new one, although persons in this state prefer to ascribe any lingering physiological arousal to their current surroundings.

• Sexual content and violence, video game addiction and violence, and temperature and violence have all been investigated using both theories.

The General Affective Aggression Model

• General affective aggression model (GAAM) suggests that individual and situational aspects influence a person's arousal, affect, and cognition, which are subject to evaluation and decision processes that result in a behavioural reaction.

• In general, distal variables are biological or environmental in nature, whereas proximal factors pertain to the qualities of the immediate surroundings and exhibit a direct influence on behaviour.

• The GAAM considers cognition to be of the utmost importance, particularly those facets that are frequently exposed to and practised.

• Instant evaluation can lead to impulsive and unconsidered acts, such as violence, however this depends greatly on the individual involved.

• When the instant evaluation is linked to an unfavourable consequence and people have sufficient time and cognitive capacities, they will engage in a reevaluation.

• During reassessment, individuals search for more social clues, recall pertinent experiences, and explore alternate interpretations for what occurred.

• GAAM has been used to explain connections between media violence and actual aggressiveness, intimate partner violence, and stalker behaviour.

• However, other researchers have contended that the GAAM does not adequately explain the entire spectrum of violent conduct, and that the supporting evidence is riddled with methodological flaws.

Personality and Violent Behavior

Personality Types, Impulsivity, and Self-Regulation

• Trait psychology has been utilised for a long time to investigate the relationship between personality and violent conduct.

• Current political developments have generated interest in Adorno's authoritarian personality, Friedman and Rosenman's type A personality, and Megargee's differentiation between under- and overcontrolled offenders.

• Subsequent research has abandoned Megargee's distinction and reconceived the issue in terms of impulsivity and self-regulation.

• Eysenck suggested that impulsivity included both adventurism and sensation-seeking.

• Personality theorists have postulated four subtraits or pathways that contribute to impulsive behaviour: urgency, lack of premeditation, lack of perseverance, and sensation seeking.

• Current research has uncovered connections between impulsivity and intimate relationship violence, suicide, personality disorder, and violence.

• Self-regulation is the capacity to manage emotional responses and analyse and choose acceptable behavioural responses.

• Harris et al. (2001) presented a two-pathway model for general criminal violence, but Cassar et al. (2003) identified four distinct self-regulation-based paths to violent behaviour.

Personality Disorders and Violence

• The DSM-5 defines a personality disorder as a lasting pattern of thought and emotion that severely impairs an individual's ability to function in daily life.

• Antisocial personality disorder (ASPD) is the most frequently addressed personality condition in relation to violence, affecting offenders more frequently than non-offenders.

• Research demonstrate that ASPD is associated with a variety of unfavourable effects. ASPD and substance use disorder have been connected to violent behaviour, and narcissistic personality disorder is also associated with violence.

• Narcissistic personality disorder refers to a pattern of grandiosity, need for adulation, and lack of empathy, which may serve to temper a person's violent tendencies.

• By disregarding negative feedback, narcissists may preserve their inflated sense of self, leading to rage and violence.

Psychopathy and Violent Behavior

• Psychopathy is a personality condition characterised by an extreme absence of empathy and concern for others.

• Three clusters of symptoms characterise psychopathy: interpersonal, emotional, and behavioural.

• Psychopaths are frequently charismatic and fascinating communicators, but they can come out as arrogant and egotistical.

  • They have committed more violent crimes than nonpsychopathic offenders, as indicated by research conducted to date.

• Psychopathy is a risk factor for violent behaviour, including homicide, and differs from other offenders in terms of motive, arousal level, victims, and level of planning.

• According to studies, psychopaths are more prone to target strangers, exhibit instrumental traits, and commit sexually violent crimes with sadistic undertones.

• There is accumulating evidence supporting the validity of the personality construct.

• The PCL-R scores of women are lower than those of men, and the average base rate of psychopathy among female convicts in penal facilities is lower.

• Gender differences may explain why psychopaths who are male are more prone to engage in physical violence, whereas psychopaths who are feminine are more likely to engage in relational aggression.

• Psychopathy has some cross-cultural validity, however there is evidence that the disorder's prevalence or severity varies from culture to culture.