1. Organized as columns perpendicular to the cortical surface

2. Columns are frequency-specific (cochlear map)

3. Divided into parallel strips running along the length of A1; columns in some strips respond to binaural stimuli; in other strips, columns respond to stimuli in a particular ear and are inhibited by input from the contralateral ear

4. Although some frequency discrimination is possible even with bilateral injury to A1, discrimination of complex sounds, such as speech, requires the auditory cortex

C. Auditory Cortex Projections

1. A1 projects to adjacent areas such as A2 (secondary auditory cortex, area 42, which also gets input from the thalamus) and speech processing areas

2. Projection areas associated with identifying significance of sounds, language, etc.