Original Research Article
No disillusions in auditory extinction: perceiving a melody comprised of unperceived notes
1 Department of Psychology and Helen Wills Neuroscience Institute, University of California, USA
2 Department of Psychology and Interdisciplinary Center for Neural Computation, The Hebrew University of Jerusalem, Israel
3 Department of Psychology, University of California, USA
4 Loewenstein Rehabilitation Hospital and Sackler faculty of Medicine, Tel Aviv University, Israel
2 Department of Psychology and Interdisciplinary Center for Neural Computation, The Hebrew University of Jerusalem, Israel
3 Department of Psychology, University of California, USA
4 Loewenstein Rehabilitation Hospital and Sackler faculty of Medicine, Tel Aviv University, Israel
The formation of coherent percepts requires grouping together spatio-temporally disparate sensory inputs. Two major questions arise: (1) is awareness necessary for this process; and (2) can non-conscious elements of the sensory input be grouped into a conscious percept? To address this question, we tested two patients suffering from severe left auditory extinction following right hemisphere damage. In extinction, patients are unaware of the presence of left side stimuli when they are presented simultaneously with right side stimuli. We used the ‘scale illusion’ to test whether extinguished tones on the left can be incorporated into the content of conscious awareness. In the scale illusion, healthy listeners obtain the illusion of distinct melodies, which are the result of grouping of information from both ears into illusory auditory streams. We show that the two patients were susceptible to the scale illusion while being consciously unaware of the stimuli presented on their left. This suggests that awareness is not necessary for auditory grouping and non-conscious elements can be incorporated into a conscious percept.
Keywords: auditory extinction, unilateral neglect, auditory scene analysis, streaming, scale illusion, implicit processing
Copyright: © 2008 Deouell, Deutsch, Scabini, Soroker and Knight. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Leon Y Deouell, Department of Psychology, The Hebrew University of Jerusalem, Jeruslaem 91905, Israel. e-mail: leon.deouell@huji.ac.il
Citation: Deouell L, Deutsch D, Scabini D, Soroker N and Knight RT (2008) No disillusions in auditory extinction: perceiving a melody comprised of unperceived notes. Front. Hum. Neurosci. (2007) 1:15. doi:10.3389/neuro.09.015.2007
Received: 16 October 2007; paper pending published: 29 November 2007; accepted: 03 January 2008; published online: 28 March 2008.
Edited by:
Robert T. Knight, University of California Berkeley, USA
Reviewed by:
William J. Jagust, University of California Berkeley, USA
George R. Mangun, University of California Davis, USA
George R. Mangun, University of California Davis, USA
*Correspondence: Leon Y Deouell, Department of Psychology, The Hebrew University of Jerusalem, Jeruslaem 91905, Israel. e-mail: leon.deouell@huji.ac.il
