1. Auditory Training Reverses Lead (Pb)-Toxicity-Induced Changes in Sound-Azimuth Selectivity of Cortical Neurons
- Author
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Yuan Cheng, Fanfan Wei, Qingyin Zheng, Guoqiang Jia, Xinde Sun, Liping Yu, Yifan Zhang, Xiaoming Zhou, Ye Shan, Diana I. Lurie, Jie Zhou, Michael M. Merzenich, Min Zhu, and Xia Liu
- Subjects
Lead Poisoning, Nervous System, Childhood ,Cognitive Neuroscience ,Auditory cortex ,Receptors, N-Methyl-D-Aspartate ,050105 experimental psychology ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Discrimination, Psychological ,Medicine ,Animals ,0501 psychology and cognitive sciences ,Sound Localization ,Lead (electronics) ,Auditory Cortex ,Neurons ,business.industry ,05 social sciences ,Pb toxicity ,Cognition ,Rodent model ,Cortical neurons ,Inhibitory neurotransmitter ,Receptors, GABA-A ,Rats ,Disease Models, Animal ,Sound ,Lead ,Excitatory postsynaptic potential ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Lead (Pb) causes significant adverse effects on the developing brain, resulting in cognitive and learning disabilities in children. The process by which lead produces these negative changes is largely unknown. The fact that children with these syndromes also show deficits in central auditory processing, however, indicates a speculative but disturbing relationship between lead-exposure, impaired auditory processing, and behavioral dysfunction. Here we studied in rats the changes in cortical spatial tuning impacted by early lead-exposure and their potential restoration to normal by auditory training. We found animals that were exposed to lead early in life displayed significant behavioral impairments compared with naïve controls while conducting the sound-azimuth discrimination task. Lead-exposure also degraded the sound-azimuth selectivity of neurons in the primary auditory cortex. Subsequent sound-azimuth discrimination training, however, restored to nearly normal the lead-degraded cortical azimuth selectivity. This reversal of cortical spatial fidelity was paralleled by changes in cortical expression of certain excitatory and inhibitory neurotransmitter receptor subunits. These results in a rodent model demonstrate the persisting neurotoxic effects of early lead-exposure on behavioral and cortical neuronal processing of spatial information of sound. They also indicate that attention-demanding auditory training may remediate lead-induced cortical neurological deficits even after these deficits have occurred.
- Published
- 2018