Neurobiological and behavioural aspects of social aggression in healthy men and women

Social aggression poses a major threat for individuals and society. The
investigation of the psychobiological underpinnings of this destructive
phenomenon is thus of critical importance. Recent evidence suggests that
hormonal imbalances in steroid hormones
and aberrant forms of cortical brain communication are associated with social
aggression.

The primary objective of the proposed study is to gain insight in the
underlying neural mechanisms by which frontal cortical activation patterns are
established, and its implications for human aggressive behaviour. The proposed
approach aims to integrate hormonal and physiological properties of
cortico-cortcal and cortico-subcortical brain communication, and relate these
properties to human aggressive behaviour.

As the proposed study aims to compare inter individual differences in
relations in hormonal, physiological and behavioural properties, this
observational study employs a between subjects design.

In order to alleviate experimental demands posed upon the participants, all
participants will perform not all tasks. Therefore, candidate participants will
be asked to perform only a subset of tasks in each of the proposed sub
experiments. The study will consist of four sub experiments, each of which will
last approximately one and a half hour. In 2 of the four proposed sub
experiments, an additional time investment of the participant will be asked
because of the collection of saliva directly after awakening, and the
collection of a saliva sample directly preceding the experimental session. The
experimental sessions will consist of the administration of two questionnaires,
a Transcranial Magnetic Stimulation session and a behavioural task. The
parameters used in the Transcranial Magnetic Stimulation session are well
within internationally accepted stimulation parameters, and bear a negligible
health risk.