A new field in monkey's frontal cortex: premotor ear-eye field (PEEF).

In macaque monkey, area 8B is cytoarchitectonically considered a transitional area between the granular Brodmann area 9, rostrally, and the rostral part of the dorsal agranular Brodmann area 6, caudally. As for electrophysiological data, microstimulation of area 8B evokes ear and/or eye movements; unit activity recording shows neurons encoding different auditory environmental stimuli and ear and/or eye movements. Moreover, visual attentive fixation modulates the discharge of auditory environmental neurons and auditory-motor neurons. As for anatomical data, area 8B is connected with auditory cortical areas, superior colliculus and cerebellum. Current functional and anatomical evidences support that area 8B is a specific Premotor Ear-Eye Field (PEEF) involved in auditory stimuli recognition and in orienting processes. In conclusion, we suggest that PEEF could play an important role in engaging the auditory spatial attention for the purpose of orienting eye and ear towards the sound source.