ABSTRACT
The temporal lobe is structurally and functionally the most diverse of the human brain, and is the most studied from a neuropsychological perspective. Its varied anatomical structures are intimately connected with extratemporal regions that together form systems necessary for auditory, visual and olfactory perception, memory, language, and emotional processing. This chapter is an attempt to synthesize the results of much of the research, conducted over the last 50 years, on the consequences of temporal lobe lesions. Memory defects constitute the best known and most intensively studied symptom of temporal lobe damage, and the phenomenology of temporal lobe memory syndromes will be discussed. The temporal lobe also contains primary auditory and olfactory cortices, and damage to these areas can result in auditory and olfactory perceptual and processing deficits. The amygdala, structurally and hodologically one of the most complex regions of the entire brain, is also located in the temporal lobe, and the most obvious effects of amygdalar damage will be presented. Visual perceptual deficits can result from damage to geniculostriate afferents in the posterior temporal lobe, or to the higherorder visual processing stream that courses anteriorly along the temporal lobe from the occipital cortex. Language deficits constitute another wellknown result of temporal lobe cortical lesions and are often seen in clinical syndromes involving temporal lobe degeneration, such as semantic dementia. An understanding of the consequences of temporal lobe damage requires both knowledge of underlying anatomy and respect for the degree to which cortical developmental plasticity can compensate for early damage.
