It is commonly assumed that different perceptual qualities arising from sensory stimuli depend on their physical nature being transformed by specific peripheral receptors, for example, colour, vibration or heat. A notable unexplained exception is the low and high repetition rates of any sound perceived as rhythm or pitch, respectively. Using auditory discrimination learning in bilaterally auditory cortex ablated animals, we demonstrate that the perceptual quality of sounds depends on the way the brain processes stimuli rather than on their physical nature. In this context, cortical and subcortical processing steps have different roles in analysing different aspects of sounds with the complete analysis accomplished not before information converges in the auditory cortex.
Leibniz Institute for Neurobiology, Magdeburg, Germany
Correspondence and requests for reprints to PD Dr Holger Schulze, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
Tel: +49 391 6263322; fax: +49 391 6263328; e-mail: Holger.Schulze@IfN-Magdeburg.de
Sponsorship: A.D. was supported by Grant SCHU-1272/2-1 of the Deutsche Forschungsgemeinschaft (DFG) to Dr Schulze.
Received 7 March 2006 accepted 26 March 2006
Current address: Dr Simone Kurt, Department of Neurobiology, University of Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany.