Brodmann area 38, also BA38 or temporopolar area 38 (H), is part of the temporal cortex in the

human brain The human brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. The brain consists of the cerebrum, the brainstem and the cerebellum. It controls most of the activities of the ...

. BA 38 is at the anterior end of the temporal lobe, known as the temporal pole. BA38 is a subdivision of the cytoarchitecturally defined temporal region of

cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of ...

. It is located primarily in the most rostral portions of the superior temporal gyrus and the

middle temporal gyrus Middle temporal gyrus is a gyrus in the brain on the temporal lobe. It is located between the superior temporal gyrus and inferior temporal gyrus. It corresponds largely to Brodmann area 21. The middle temporal gyrus is bounded by: * the superi ...

. Cytoarchitecturally it is bounded caudally by the

inferior temporal area 20 Brodmann area 20, or BA20, is part of the temporal cortex in the human brain. The region encompasses most of the ventral temporal cortex, a region believed to play a part in high-level visual processing and recognition memory. This area is also ...

, the middle temporal area 21, the

superior temporal area 22 Brodmann area 22 is a Brodmann's area that is cytoarchitecturally located in the posterior superior temporal gyrus of the brain. In the left cerebral hemisphere, it is one portion of Wernicke's area. The left hemisphere BA22 helps with generati ...

and the

ectorhinal area 36 Brodmann area 35, together with Brodmann area 36, comprise the perirhinal cortex. They are cytoarchitecturally defined temporal regions of the cerebral cortex. Human Brodmann area 35 This area is known as perirhinal area 35. It is a subdivision ...

(Brodmann-1909). The temporal pole is a paralimbic region involved in high level semantic representation and socio-emotional processing. The

uncinate fasciculus The uncinate fasciculus is a white matter association tract in the human brain that connects parts of the limbic system such as the temporal pole, anterior parahippocampus, and amygdala in the temporal lobe with inferior portions of the frontal l ...

provides a direct bidirectional path to the orbitofrontal cortex, allowing mnemonic representations stored in the temporal pole to bias decision making in the frontal lobe. The temporal pole appears to be a convergence zone where concepts (also known as

semantic memories Semantic memory refers to general world knowledge that humans have accumulated throughout their lives. This general knowledge (word meanings, concepts, facts, and ideas) is intertwined in experience and dependent on culture. We can learn about n ...

) that are stored in the ventral anterior temporal lobe are imbued with emotional significance and personal meaning. In addition, concepts of individual people, abstracted away from the perceptual representations, are stored in a “face patch” in the temporal pole. This face patch is found in both non-human primates and humans. This relates to early work showing that damage to the temporal pole can cause an amnestic

prosopagnosia Prosopagnosia (from Greek ''prósōpon'', meaning "face", and ''agnōsía'', meaning "non-knowledge"), also called face blindness, ("illChoisser had even begun tpopularizea name for the condition: face blindness.") is a cognitive disorder of fac ...

in which knowledge of familiar people is lost. Bilateral damage to the temporal poles, though rare, can cause dramatic changes in personality. Kluver-Bucy syndrome involves damage to the greater temporal pole as well as the

amygdala The amygdala (; plural: amygdalae or amygdalas; also '; Latin from Greek, , ', 'almond', 'tonsil') is one of two almond-shaped clusters of nuclei located deep and medially within the temporal lobes of the brain's cerebrum in complex verteb ...

. In this disorder, people and animals demonstrate fearlessness, hypersexuality, and hyperorality This area is among the earliest affected by

Alzheimer's disease Alzheimer's disease (AD) is a neurodegeneration, neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in short-term me ...

frontotemporal dementia Frontotemporal dementia (FTD), or frontotemporal degeneration disease, or frontotemporal neurocognitive disorder, encompasses several types of dementia involving the progressive degeneration of frontal and temporal lobes. FTDs broadly present as ...

frontotemporal lobar degeneration Frontotemporal lobar degeneration (FTLD) is a pathological process that occurs in frontotemporal dementia. It is characterized by atrophy in the frontal lobe and temporal lobe of the brain, with sparing of the parietal and occipital lobes. Commo ...

, and is commonly involved at the start of temporal lobe seizures. Cytoarchitectonic and chemoarchitectonic studies find that it contains at least seven subareas, one of which, "TG", is unique to humans.

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38 Temporal lobe {{neuroanatomy-stub

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