Auditory cortex

Auditory Cortex

The auditory cortex is the part of the temporal lobe that processes auditory information in humans and many other vertebrates. It is a part of the auditory system, performing basic and higher functions in hearing, such as possible relations to language switching.

Structure

The auditory cortex is divided into three separate parts: the primary, secondary, and tertiary auditory cortex. These areas are distinguished by their different neuronal structures and connections, and they perform different functions in the processing of auditory information.

Primary Auditory Cortex

The primary auditory cortex (A1) is the first cortical destination of auditory information originating from the cochlea. It is located on the superior temporal gyrus in the dominant cerebral hemisphere, which is the left hemisphere in about 97% of right-handed individuals and 70% of left-handed individuals.

Secondary Auditory Cortex

The secondary auditory cortex (A2) receives input from A1 and from various other brain areas. It is involved in the interpretation of the basic characteristics of sound such as pitch and volume.

Tertiary Auditory Cortex

The tertiary auditory cortex has multiple inputs and outputs with the primary and secondary auditory cortexes, as well as various other brain areas. It is involved in higher level processing of complex sounds, and is thought to play a role in the perception and recognition of speech and music.

Function

The auditory cortex is involved in tasks such as identifying and segregating auditory "objects" and detecting the location of a sound in space. It also plays a key role in the perception of music and other complex sounds, as well as in the understanding and production of speech.

Clinical Significance

Damage to the auditory cortex can result in auditory agnosia, a condition in which an individual has difficulty recognizing or interpreting sounds, despite having normal hearing. Other conditions associated with damage to the auditory cortex include tinnitus, hyperacusis, and various forms of auditory hallucination.

See Also

• Neuroscience
• Neuroanatomy
• Auditory system
• Temporal lobe