The neural correlates of 'deaf-hearing' in man : Conscious sensory awareness enabled by attentional modulation

• Published in: Brain (London, England : 1878) Vol. 123; no. 3; pp. 532 - 545
• Main Authors: ENGELIEN, A, HUBER, W, SILBERSWEIG, D, STERN, E, FRITH, C. D, DÖRING, W, THRON, A, FRACKOWIAK, R. S. J
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.03.2000; Oxford Publishing Limited (England)
• Subjects: Acoustic Stimulation; Adult; Attention - physiology; Audiometry; Auditory Cortex - blood supply; Auditory Cortex - physiopathology; Biological and medical sciences; Consciousness - physiology; Hearing Loss, Central - diagnostic imaging; Hearing Loss, Central - etiology; Hearing Loss, Central - physiopathology; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Neurology; Neuropsychological Tests; Reaction Time - physiology; Stroke - complications; Tomography, Emission-Computed; Vascular diseases and vascular malformations of the nervous system; Volition - physiology; Radionuclide study; Human; Central hearing loss; Nervous system diseases; Stroke; Pathophysiology; Middle cerebral artery; Auditory attention; Auditory disorder; Cardiovascular disease; Retrocochlear hearing loss; Nuclear magnetic resonance imaging; Auditory cortex; Cerebral disorder; Vascular disease; Case study; Central nervous system disease; Medical imagery; Perception hearing loss; Cerebrovascular disease; Positron; Emission tomography
• ISSN: 0006-8950; 1460-2156; 1460-2156
• DOI: 10.1093/brain/123.3.532

Attentional modulation of normal sensory processing has a two-fold impact on human brain activity: activation of a network of localized brain regions is associated with paying attention, and activation of specific sensory regions is enhanced relative to passive stimulation. The mechanisms underlying attentional modulation of perception in patients with lesions of sensory cortices are less well understood. Here we report a unique patient suffering from extensive bilateral destruction of the auditory cortices (including the primary auditory fields) who demonstrated conscious perception of the onset and offset of sounds only when selectively attending to the auditory modality. This is the first description of such an attentively modulated 'deaf-hearing' phenomenon and its neural correlates, using H(2)(15)O-PET. Increases in cerebral blood flow associated with conscious awareness of sound that was achieved by listening attentively (compared with identical auditory stimulation presented when the patient was inattentive) were found bilaterally in the lateral (pre)frontal cortices, the spared middle temporal cortices and the cerebellar hemispheres. We conclude that conscious awareness of sounds may be achieved in the absence of the primary auditory cortex, and that selective, 'top-down' attention, associated with prefrontal systems, exerts a crucial modulatory effect on auditory perception within the remaining auditory system.