- Email: [email protected]
An overview of the neural circuitry for sound processing
Neuroscience and Biobehavioral Reviews 35 (2011) 2045
Contents lists available at ScienceDirect
Neuroscience and Biobehavioral Reviews journal homepage: www.elsevier.com/locate/neubiorev
Editorial
An overview of the neural circuitry for sound processing
Keywords: Neural circuit Auditory plasticity Sound information processing
Hearing is a sense focused on the processing of sound information. This everyday occurrence is neither simple nor effortless and the brain is remarkably enabled to extract and process relevant sounds in the presence of many others, which is an ability often referred to as the cocktail-party effect. Auditory physiologists and neuroscientists have been challenged by the neural circuitry that underlies several important processes. How is the brain wired for the processing, analysis, integration and extraction of information carried by acoustic waves? How is the brain re-wired in response to previous experience? This special issue presents thirteen articles that examine this theme from various perspectives. Although the cocktail-party effect was proposed by Cherry in 1953, our understanding of the underlying neural mechanisms remains incomplete. Dr. Li and his colleagues explore the frequency-following responses of the brain as a valuable measure for investigating the neural circuits underlying cocktail-party effect. Frequency, intensity and timing are fundamental parameters of acoustic waves. Neural circuits for extracting and representing auditory information based on these sound parameters are studied in three articles. Dr. Metherate focuses on the processing and integration of sound spectral information in cortical circuits including the thalamocortical pathway, the long-range intracortical pathway and cholinergic modulation. Dr. Barbour investigates a rarely attended issue: how the auditory system represents sounds invariantly across the full intensity range of hearing. Drs. Wenstrup and Portfors explore the computational power of the auditory midbrain for target-distance information, extracting the echo delay from the emitted biosonar pulse in echo-locating bats. Authors further exhibit the transmission of target-distance information from the auditory midbrain to other brain regions for further analysis and for rapid adjustments in flight and vocalization. The interplay of excitation and inhibition in thalamocortical and cortical circuits is a rapidly expanding topic and is featured in four papers. Dr. Ojima discusses the interaction of excitatory and inhibitory synaptic inputs for suppressive responses in the auditory cortex based on intra-cell recording with a sharp glass electrode. The same interaction and its impact on the receptive field of cortical neurons using in vivo whole-cell voltage-clamp recording are addressed by Dr. Zhang and his colleagues. Drs. Froemke and Jones 0149-7634/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.neubiorev.2011.07.003
highlight the establishment of the neuronal receptive field during early development. Dr. Yan and his colleagues further address the developmental issue and specifically comment on the impact of drastic changes in thalamocortical inputs. Similar to other sensory systems, the central auditory system is dynamic. Its function is altered following auditory learning/experience and ear trauma. Drs. Pienkowski and Eggermont review experience-driven auditory plasticity in frequency maps and discuss putative mechanisms. They also emphasize that the mature auditory brain is more plastic than previously thought. Dr. King and his colleagues present evidence of long-term and short-term auditory plasticity for sound localization during development and adulthood. Drs. Pantev and Herholz show this dramatic capacity of the brain in human subjects, i.e., the auditory plasticity following music training. Given the facts that auditory plasticity is primarily guided by auditory cues and that the thalamocortical system transmits precise auditory information to the auditory cortex, Dr. Yan and his colleagues focus on the thalamocortical mechanism involved in sound-guided plasticity in the auditory cortex. This special issue concludes with an article by Drs. Arnott and Alain who draw our attention to a unique issue on the dualstream model of auditory perception. They argue that the auditory dorsal pathway can be understood as one concerned with the goaldirected action of guiding the eyes to a location of interest in the visual field. Their explanation of the function of the dorsal pathway provides a more ecologically valid perspective on auditory processing in dorsal brain regions. We thank all of the authors for their significant contributions to our field. Their work not only provides critical commentary on past progress but it also presents new ideas and future directions for studies of the neural interactions involved in hearing. Jun Yan ∗ University of Calgary, Department of Physiology and Pharmacology, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1 Liang Li Peking University, China ∗ Corresponding
author. Tel.: +1 403 220 5518; fax: +1 403 283 8731. E-mail address:[email protected] (J. Yan) 24 June 2011
Contents lists available at ScienceDirect
Neuroscience and Biobehavioral Reviews journal homepage: www.elsevier.com/locate/neubiorev
Editorial
An overview of the neural circuitry for sound processing
Keywords: Neural circuit Auditory plasticity Sound information processing
Hearing is a sense focused on the processing of sound information. This everyday occurrence is neither simple nor effortless and the brain is remarkably enabled to extract and process relevant sounds in the presence of many others, which is an ability often referred to as the cocktail-party effect. Auditory physiologists and neuroscientists have been challenged by the neural circuitry that underlies several important processes. How is the brain wired for the processing, analysis, integration and extraction of information carried by acoustic waves? How is the brain re-wired in response to previous experience? This special issue presents thirteen articles that examine this theme from various perspectives. Although the cocktail-party effect was proposed by Cherry in 1953, our understanding of the underlying neural mechanisms remains incomplete. Dr. Li and his colleagues explore the frequency-following responses of the brain as a valuable measure for investigating the neural circuits underlying cocktail-party effect. Frequency, intensity and timing are fundamental parameters of acoustic waves. Neural circuits for extracting and representing auditory information based on these sound parameters are studied in three articles. Dr. Metherate focuses on the processing and integration of sound spectral information in cortical circuits including the thalamocortical pathway, the long-range intracortical pathway and cholinergic modulation. Dr. Barbour investigates a rarely attended issue: how the auditory system represents sounds invariantly across the full intensity range of hearing. Drs. Wenstrup and Portfors explore the computational power of the auditory midbrain for target-distance information, extracting the echo delay from the emitted biosonar pulse in echo-locating bats. Authors further exhibit the transmission of target-distance information from the auditory midbrain to other brain regions for further analysis and for rapid adjustments in flight and vocalization. The interplay of excitation and inhibition in thalamocortical and cortical circuits is a rapidly expanding topic and is featured in four papers. Dr. Ojima discusses the interaction of excitatory and inhibitory synaptic inputs for suppressive responses in the auditory cortex based on intra-cell recording with a sharp glass electrode. The same interaction and its impact on the receptive field of cortical neurons using in vivo whole-cell voltage-clamp recording are addressed by Dr. Zhang and his colleagues. Drs. Froemke and Jones 0149-7634/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.neubiorev.2011.07.003
highlight the establishment of the neuronal receptive field during early development. Dr. Yan and his colleagues further address the developmental issue and specifically comment on the impact of drastic changes in thalamocortical inputs. Similar to other sensory systems, the central auditory system is dynamic. Its function is altered following auditory learning/experience and ear trauma. Drs. Pienkowski and Eggermont review experience-driven auditory plasticity in frequency maps and discuss putative mechanisms. They also emphasize that the mature auditory brain is more plastic than previously thought. Dr. King and his colleagues present evidence of long-term and short-term auditory plasticity for sound localization during development and adulthood. Drs. Pantev and Herholz show this dramatic capacity of the brain in human subjects, i.e., the auditory plasticity following music training. Given the facts that auditory plasticity is primarily guided by auditory cues and that the thalamocortical system transmits precise auditory information to the auditory cortex, Dr. Yan and his colleagues focus on the thalamocortical mechanism involved in sound-guided plasticity in the auditory cortex. This special issue concludes with an article by Drs. Arnott and Alain who draw our attention to a unique issue on the dualstream model of auditory perception. They argue that the auditory dorsal pathway can be understood as one concerned with the goaldirected action of guiding the eyes to a location of interest in the visual field. Their explanation of the function of the dorsal pathway provides a more ecologically valid perspective on auditory processing in dorsal brain regions. We thank all of the authors for their significant contributions to our field. Their work not only provides critical commentary on past progress but it also presents new ideas and future directions for studies of the neural interactions involved in hearing. Jun Yan ∗ University of Calgary, Department of Physiology and Pharmacology, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1 Liang Li Peking University, China ∗ Corresponding
author. Tel.: +1 403 220 5518; fax: +1 403 283 8731. E-mail address:[email protected] (J. Yan) 24 June 2011