Glazewski Stanislaw, Benedetti Brett L, Barth Alison L
Institute for Science and Technology in Medicine and School of Life Sciences, Keele University, Keele, Staffordshire ST5 5BG, United Kingdom.
J Neurosci. 2007 Apr 4;27(14):3910-20. doi: 10.1523/JNEUROSCI.0181-07.2007.
Each cerebral hemisphere processes sensory input from both sides of the body, but the impact of this convergence on shaping and modifying receptive field properties remains controversial. Here we investigated the effect of chronic deprivation of ipsilateral sensory whiskers on receptive field plasticity in primary somatosensory cortex. In the absence of ipsilateral whiskers, cortical receptive fields were significantly larger than control after 1 week. Removal of all but a single whisker from one side of the face [single-whisker experience (SWE)] has been shown to result in the expansion of the cortical area responding to the spared whisker. We compared the effects of SWE in the presence (SWE-unilateral) and absence (SWE-bilateral) of ipsilateral whiskers. SWE-bilateral deprivation results in a significant increase in neuronal responses to spared whisker stimulation both in its cognate barrel column and in adjacent, surrounding barrel columns compared with control and SWE-unilateral deprived animals. Surround receptive fields in deprived columns were maintained in SWE-bilateral treated animals but depressed in SWE-unilateral animals. The increase in spared whisker responses was progressive with longer deprivation periods. These data show that ipsilateral whiskers can constrain receptive field size in the barrel cortex.
每个大脑半球都处理来自身体两侧的感觉输入，但这种汇聚对塑造和改变感受野特性的影响仍存在争议。在这里，我们研究了同侧感觉触须长期剥夺对初级体感皮层感受野可塑性的影响。在没有同侧触须的情况下，1周后皮层感受野明显大于对照组。从面部一侧去除除一根触须外的所有触须[单触须体验（SWE）]已被证明会导致对留存触须做出反应的皮层区域扩大。我们比较了在存在（SWE-单侧）和不存在（SWE-双侧）同侧触须的情况下SWE的影响。与对照组和SWE-单侧剥夺动物相比，SWE-双侧剥夺导致留存触须刺激在其同源桶状柱和相邻的周围桶状柱中的神经元反应显著增加。在SWE-双侧处理的动物中，剥夺柱中的周围感受野得以维持，但在SWE-单侧动物中则受到抑制。留存触须反应的增加随着剥夺时间的延长而逐渐增加。这些数据表明同侧触须可以限制桶状皮层中的感受野大小。
