Information about the behavioural and psychological correlates of alph
a(2)-adrenoceptor stimulation has arisen from manipulations and record
ings of the activity of the rostral noradrenergic projection from the
nucleus locus coeruleus in a variety of species. The results of anatom
ical and chemical lesioning experiments, direct electrical stimulation
, the effects of alpha(2)-adrenoceptor agonists and antagonists and si
ngle unit recordings combine to develop a view that the brain noradren
ergic system plays an important role in mediating changes in cortical
and perhaps thalamic activity that underly the direction of attention.
Inputs into the nucleus locus coeruleus are such that this projection
might subserve the contribution of somatic markers to decision-making
and behaviour.