Siucinska E, Kossut M
Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, ul. Pasteura 3, 02-093 Warsaw, Poland.
Neuroscience. 2004;127(4):961-71. doi: 10.1016/j.neuroscience.2004.06.004.
Sensory experience and learning can modify cortical body maps. We have previously reported that 3 days of classical conditioning, in which stimulation of a row of whiskers was paired with tail shock, produced an expansion of the cortical representation of the "trained row" labeled with 2-deoxyglucose (2DG), in layer IIIb and IV of the barrel cortex. The present study examined plastic remodelling of the vibrissal cortical representation after pairing whisker stimulation with a drop of sweet water. Cortical representations of rows of whiskers were mapped by 2DG autoradiography after 3 days and 2 months of training. The training resulted in enlargement of the cortical representation of vibrissae involved in the stimulus pairing compared with the contralateral representation of a row of whiskers, that were not touched during the training. This modification of whisker representation was different after short-term and long-term appetitive training. After three pairing sessions, changes in the width of cortical representation were visible in layers II/IIIa (29%) and layers V/VI (28%). After 2 months of training, significant changes in the width of cortical representation row B were found only in layer IV (41%). The changes were not observed in animals, that received whisker stimulation alone or in those who were subjected to training with unpaired stimuli. The results demonstrate that stimulus-pairing-induced changes in cortical whisker representation appeared with different time courses at different levels of cortical columnar information processing.
感觉体验和学习能够改变皮层躯体图谱。我们之前曾报道，连续3天进行经典条件反射实验，即对一排触须进行刺激并同时施加尾部电击，会使桶状皮层IIIb层和IV层中用2-脱氧葡萄糖（2DG）标记的“受训练排”的皮层表征发生扩展。本研究考察了将触须刺激与一滴糖水配对后，触须皮层表征的可塑性重塑。在训练3天和2个月后，通过2DG放射自显影法绘制了各排触须的皮层表征图。与训练期间未被触碰的一排触须的对侧表征相比，训练导致参与刺激配对的触须的皮层表征扩大。短期和长期的味觉性训练后，触须表征的这种改变有所不同。经过三次配对实验后，皮层表征宽度的变化在II/IIIa层（29%）和V/VI层（28%）可见。经过2个月的训练后，仅在IV层发现皮层表征B排的宽度有显著变化（41%）。在仅接受触须刺激的动物或接受非配对刺激训练的动物中未观察到这种变化。结果表明，刺激配对诱导的皮层触须表征变化在皮层柱状信息处理的不同水平上呈现出不同的时间进程。
