Middle temporal gyrus
The middle temporal gyrus is one of three gyri on the lateral surface of the temporal lobe.
The middle temporal gyrus is bounded dorsally by the superior temporal sulcus and superior temporal gyrus and ventrally by the inferior temporal sulcus and inferior temporal gyrus. It extends posteriorly from the temporal pole, blending into the parietal and occipital lobes with the limits defined by an arbitrary line, the lateral parietotemporal line .
The middle temporal gyrus is supplied by all 4 temporal branches of the middle cerebral artery that emerge from the lateral sulcus .
Recent tractography-based parcellation of the MTG identified four distinct subregions based on anatomical connectivity, with each subregion involved in unique functions :
- anterior middle temporal gyrus (aMTG)
- sound recognition and semantic retrieval
- middle middle temporal gyrus (mMTG)
- semantic memory
- posterior middle temporal gyrus (pMTG)
- language processing
- sulcus middle temporal gyrus (sMTG)
- decoding gaze direction and intelligible speech and processing of verbal mental arithmetic
Lesions in the pMTG result in deficits in language comprehension (Wernicke's aphasia) .