Auditory cortex
The auditory or auditory cortex (from Latin audire = German "to hear" or Latin auditio = German "hearing" and Latin cortex = German "cortex") - also called the hearing center or auditory cortex - is the Area of the cerebral cortex that is used to process and become aware of acoustic stimuli . It is therefore the end point of the hearing path .
Anatomical location
In humans, the auditory cortex lies on the upper turn of the temporal lobe , the superior temporal gyrus . A considerable part lies in the depth of the Sylvian groove ( fissura lateralis ), and is covered by the frontal and parietal lobes ; these are the gyri temporales transversi , which are also known as Heschl's transverse windings (after Richard Heschl ). The Wernicke area on the supramarginal gyrus , which is assigned to speech understanding , is sometimes assigned to the auditory cortex. According to Korbinian Brodmann's brain atlas , the auditory cortex corresponds to the Brodmann areas 41 , 42 and 22 and to some extent area 52 . Microanatomically, it is a six-layer isocortex .
Structure and function
The primary ( A1, BA 41 ), the secondary ( A2, BA 42 ) and the tertiary auditory area surround each other concentrically . Similar to all primary receptive fields , the primary hearing field shows a spatial organization: in this case it is the frequencies in several places that have a continuous representation, the so-called tonotopy . So you can draw several maps of the represented frequencies on the brain surface. The secondary and tertiary fields are associative; In other words , they are used primarily to compare, classify and evaluate current hearing information with familiar ones . This happens mostly unconsciously. On the other hand, auditory stimuli penetrate into the consciousness that are unknown or not classifiable or that potentially indicate something threatening (“warning stimuli”), as well as everything on which one concentrates . The most important functional part of the auditory cortex in humans is speech understanding.
See also
literature
- Otto Detlev Creutzfeldt : Cortex Cerebri . Springer Verlag, 1992, ISBN 3-540-12193-5 , 484 pp.
- Karl Zilles, Gerd Rehkämper: Functional Neuroanatomy . 3. Edition. Springer, 1993, ISBN 3-540-54690-1 , 454 pp.
- Alfred Benninghoff , Detlev Drenckhahn et al .: Anatomy. Macroscopic anatomy, embryology and histology of humans . Volume 2. 15th edition. Urban & Schwarzenberg, 1994, ISBN 3-541-00255-7
