Sensory Experience and Cortical Plasticity.ppt

Sensory Experience and Cortical Plasticity Michael P. Kilgard Frequency Bandwidth is Shaped by Spatial and Temporal Stimulus Features Sensory Experience Controls: Response Strength Cortical Topography Receptive Field Size Maximum Following Rate Synchronization Spectrotemporal Selectivity Training Experiments - Navzer Engineer Amanda Puckett Crystal Novitski Enrichment Experiments - Navzer Engineer Cherie Percaccio Receptive Field Plasticity - Pritesh Pandya Synchrony Experiments - Jessica VazquezFM Experiments - Raluca Moucha Speech Experiments - Pritesh Pandya   ‘SASH’ Group - Spectrotemporal discharge patterns of A1 neurons to ‘sash’ vocalization (n= 5 rats) kHz 16kHz @50dB: 35 % ? 1.9 55 % ? 5.3 (p0.0005) Activity from a single A1 neuron recorded in an awake rat in response to normal and enhanced human speech sounds Behavioral Relevance Neural Activity - Internal Representation External World -Sensory Input Neural Plasticity - Learning and Memory Plasticity Rules - Educated Guess Behavioral Change and Acknowledgements: and * University of Texas at Dallas 20±10 vs. 75±20 μV 81±19 vs. 37±20 μV Red Group Enriched Blue Enriched Environmental Enrichment 22 rats total 40% increase in response strength 1.4 vs. 1.0 spikes per noise burst (p 0.0001) 10% decrease in frequency bandwidth 2.0 vs. 2.2 octaves at 40dB above threshold (p 0.05) Three decibel decrease in threshold 17 vs. 20 dB ms (p 0.001) Enriched Standard A1 Enrichment Effects - after 2 months N = 16 rats, 820 sites Stronger, More Selective, and More Sensitive Environmental Enrichment Improves Response Strength, Threshold, Selectivity, and Latency of Auditory Cortex Neurons Engineer ND, Percaccio CR, Pandya PK, Moucha R, Rathbun DL, Kilgard MP. Journal of Neurophysiology, 2004. High Low Cochlea Cortex High Low Cochlea Cortex