Neuroanatomy 

The symptoms, signs, and syndromes of psychiatry, whether organic or biological psychiatric disease or not, in the main reflect alterations in functions which reside in the cerebral cortex, including the limbic lobe, and those structures and pathways closely related to the cortex. These cortical manifestations of psychiatric disease include alterations in thought, language, perception, mood, memory, motivation, personality, behaviour, and intellect. Therefore, this brief account of brain structures and pathways that are important in psychiatry will concentrate on the cerebral cortex and related structures and pathways. Readers who require a fuller account of central nervous system anatomy are referred to the many standard texts, which give a more complete coverage of the subject. Broadly speaking, neuroanatomy can be subdivided into two parts—the topographical organization of the brain and spinal cord, and the anatomical connections forming functional pathways in the central nervous system. The former is of vital importance clinically, since pathologies rarely respect the boundaries of functional systems, and knowledge of the spatial relationships of different brain structures is increasingly useful as modern imaging methods more accurately visualize detailed brain structure in vivo. However, it is the second subdivision of the subject which makes the greater contribution to understanding the biological basis of psychiatric disease, and it is this that will be at the centre of the present account.