Neuroanatomy of Neuropsychiatry (with Treatment Implications)

Abstract

Neuroanatomy is perhaps the most fundamental prerequisite for clinical neuropsychiatry as it illustrates the neural organisation of human behaviour. The neurone doctrine is the concept that the nervous system is made up of discrete individual cells called neurons. Information is mainly transmitted via electrical currents within cells (action potential) and via neurotransmitters (synapsis) between cells. Certain aspects of neuroanatomy and neurophysiology are particularly relevant to the understanding of the brain bases of neuropsychiatric conditions. The frontal lobe has long been recognised as a key area for the regulation of behaviour. This has been confirmed by the clinical characterisation of three prefrontal syndromes (orbitofrontal, ventromedial, and dorsolateral syndrome) encompassing behaviour and cognition. The basal ganglia have been shown to be key components of frontal-subcortical circuits, also referred to as cortico-striato-thalamo-cortical loops. The so-called limbic loop is of central importance to neuropsychiatry, as it connects the basal ganglia with the limbic system. The term ‘limbic system’ indicates a network of interconnected structures in the temporal lobe and diencephalon strongly associated with the processing of primary emotions and memory. Neuropsychiatrists have long used the lesion method to explore the distributed brain networks subserving specific behavioural functions. This method has recently been complemented by sophisticated neurophysiological and neuroimaging techniques. Treatment interventions for neuropsychiatric conditions encompass behavioural, pharmacological, and surgical therapies and often rely on in-depth understanding of the underlying brain processes.

An interest in the brain requires no justification other than a curiosity to know why we are here, what we are doing here, and where we are going

Paul MacLean (1913–2007)