Desensitisation and Cognitive Priming

Drug-Based Approaches

SSRIs

Selective serotonin reuptake inhibitors (e.g. fluoxetine) block the reabsorption of serotonin in synaptic clefts, increasing availability of the neurotransmitter. Because low serotonin is associated with impulsive aggression, SSRIs are used to moderate aggressive behaviour in clinical populations. Coccaro and Kavoussi (1997) conducted a randomised controlled trial with patients diagnosed with personality disorders and found that fluoxetine significantly reduced irritability and aggressive outbursts compared to placebo over a 12-week period. The effect was sustained across the trial with few dropouts.

Mood Stabilisers — Lithium

Sheard et al. (1976) conducted a double-blind, placebo-controlled trial of lithium carbonate in a prison population. Inmates receiving lithium showed a significant reduction in violent incidents and infractions compared to those receiving placebo. This RCT design provides strong evidence for lithium's causal effect on institutionalised aggression. However, lithium has a narrow therapeutic window: levels slightly above the therapeutic range are toxic.

Anti-Androgens

Anti-androgens (e.g. medroxyprogesterone acetate, MPA; cyproterone acetate) reduce testosterone synthesis or block testosterone receptors, thereby decreasing the hormonal contribution to aggression. Bradford (1988) found that MPA treatment was associated with approximately a 48% reduction in sexual offence recidivism compared to untreated controls. Anti-androgens are used primarily in the management of sexual aggression and paraphilias.

Surgical and Neural Interventions

Mark and Ervin (1970) reported cases in which surgical lesions of the amygdala reduced violent outbursts in patients with temporal lobe epilepsy. Deep brain stimulation (DBS) offers a more reversible alternative: electrodes implanted in subcortical regions allow ongoing modulation of activity. However, these interventions raise profound ethical issues: they are invasive, largely irreversible (in the case of ablation), target brain regions identified on the basis of correlation rather than established causation, and may suppress behaviour beyond aggression.

Evaluation

RCT evidence for SSRIs (Coccaro & Kavoussi, 1997) and lithium (Sheard et al., 1976) is methodologically strong — random assignment and blinding permit causal inference. However, generalisability is limited: samples tend to be clinical or institutional populations, and findings may not apply to the general population.

A fundamental critique is that biological approaches are reductionist: they target physiological mechanisms whilst ignoring the social, cognitive, and developmental factors that also drive aggression. Drug treatments reduce biological predisposition but do not address learned patterns of violence, hostile attribution biases, or socioeconomic risk factors. Aggression is likely to return if medication is discontinued without additional psychological intervention.

Significant ethical concerns arise, particularly in institutional contexts: can consent be genuinely free when offered in prison or under legal compulsion? The use of anti-androgens as a condition of parole raises issues of autonomy and bodily integrity. Surgical interventions (amygdaloid ablation) are irreversible and have been associated with broader personality changes beyond the reduction of aggression.