Lack of attention for link between sleeping problems and aggression in forensic psychiatry

Forensic psychiatric patients are more likely to have sleeping problems. According to Jeanine Kamphuis, sleeping problems could play a role in aggressive and unacceptable behaviour. Her research involved studying human patients and conducting behavioural experiments on rats. Kamphuis will be awarded a PhD by the University of Groningen on 27 March 2017.

We've all been there: sudden bouts of ill temper the day after a bad night’s sleep. Lack of sleep or poor sleep quality can affect our behaviour. ‘Until recently, psychiatry paid very little attention to sleep deprivation’, explains forensic psychiatrist Jeanine Kamphuis. There were, however, suspicions that forensic psychiatric patients had more than their fair share of sleeping problems.

Self-assessment

While training to become a psychiatrist, Kamphuis tried to establish a link between sleep and aggression. Working with the research group at the Forensic Psychiatric Clinic Assen, she analysed the sleep patterns of the patients and examined their own assessments of their bouts of aggression. She also asked the staff to assess the levels of aggression, while she spoke to patients about incidents that had taken place. ‘This gave us a more objective picture of the aggression, which we could use alongside the patients’ self-assessment. This element had been missing in previous studies of similar groups.’

Clear link

Kamphuis found a clear link between sleeping problems and aggression. Interpreting her findings is tricky: ‘We cannot be entirely sure that sleeping problems are causing the aggression. Aggressive behaviour could, for example, be causing the sleeping problems.’ She does, however, see sufficient reason for treating patients’ sleeping problems with behavioural therapy. ‘In a follow-up study, a new PhD candidate will try to find out whether aggression decreases if patients sleep better.’

Experiments on rats

Kamphuis also carried out experiments on rats. She used a colony from the University of Groningen, which displayed wide genetic and behavioural diversity. ‘Some rats are more aggressive than others, just like people. We wanted to see how they would react to sleep deprivation.’ Although they did not become more aggressive when deprived of sleep, Kamphuis did notice an effect in an experiment that monitored ‘impulse control’.

Impulse control

In this experiment, the rats were given a ball of food when they depressed a pedal, but only if they did so at intervals of 30 seconds or more. The rats that had not had enough sleep were less able to be patient. ‘Impulses are controlled in the prefrontal cortex, an area that keeps the amygdala, the brain’s emotion centre, in check. We know from previous research that in humans, the prefrontal cortex is less efficient after a night without sleep.’ Follow-up studies may shed more light on the molecular mechanisms that a play a role in this process.

Risk assessments

The picture painted by this research is more complex than Kamphuis had initially assumed. ‘We thought we'd find a one-on-one correlation between sleep and aggression. Although this doesn't appear to be the case, this is the first piece of research that clearly establishes the role that sleep plays.’ Kamphuis would now like to see sleep used as an aspect of patient evaluations in forensic psychiatry. ‘We should be looking at the sleeping patterns of patients at the time an offence was committed. And we should take sleep into account in our periodical risk assessments.’

CV

Jeanine Kamphuis studied medicine at the University of Groningen, completing her training as a psychiatrist in 2010. Since 2014, she has worked as a forensic psychiatrist in the Forensic Psychiatric Clinic Assen. The animal research was carried out in the department of Behavioural Biology of the GELIFES research institute. Kamphuis will be awarded a PhD by the Faculty of Science and Engineering on 27 March 2017 at 11 a.m. Her supervisors are Prof. J.M. Koolhaas and Prof. D.J. Dijk.

Her thesis entitled The relation between sleep and violent aggression can be downloaded here:
The relation between sleep and violent aggression