Brodmann areas 3, 1, and 2 correspond to which cortical region?

• A. Motor cortex
• B. Primary auditory cortex
• C. Angular gyrus
• D. Somatosensory

Answer: (D)

The concept being tested is how Brodmann areas map to specific cortical regions. Areas 3, 1, and 2 form the primary somatosensory cortex, located in the postcentral gyrus of the parietal lobe. This region receives tactile and proprioceptive information from the body, organized in a somatotopic map so that different body parts are represented in a orderly layout. Areas 3, 1, and 2 are primarily involved in processing basic touch sensations—texture, pressure, and proprioception—often with 3b acting as a main input and 1 and 2 refining and integrating the signal.

In contrast, the motor cortex lies in the precentral gyrus (area 4), responsible for voluntary movement. The primary auditory cortex sits in the transverse temporal gyrus (areas 41 and 42). The angular gyrus, located in the inferior parietal lobule (area 39), participates in higher-level tasks like language and number processing. Because Brodmann areas 3, 1, and 2 are the somatosensory regions, they match the somatosensory description.