Excitatory and inhibitory receptive fields of tectal cells are differentially modified by magnocellular and parvocellular divisions of the pigeon nucleus isthmi |
| |
Authors: | Y Wang J Xiao S-R Wang |
| |
Institution: | (1) Laboratory for Visual Information Processing, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China e-mail: wangsr@sun5.ibp.ac.cn Tel.: +86-10-6488-9858/8528, CN |
| |
Abstract: | It has been known that magnocellular and parvocellular divisions of the pigeon nucleus isthmi exert excitatory and inhibitory
actions on tectal cells, respectively. The present study shows that injection of N-methyl-D-aspartate into the parvocellular division results in an increase in responsive strength and extent of the inhibitory
receptive fields, which expand into the excitatory receptive fields of tectal cells. This injection concurrently leads to
a decrease in responsiveness and extent of the excitatory fields. On the other hand, injection of acetylcholine into the magnocellular
division enhances visual responsiveness, although the excitatory field is not obviously changed in extent. Meanwhile, strength
and extent of the inhibitory fields are decreased by acetylcholine. The excitatory and inhibitory fields are reduced in both
strength and extent by magnocellular and parvocellular injection of lidocaine, respectively. It suggests that isthmic inputs
from both parvocellular and magnocellular divisions converge onto the same tectal cells, and the magnocellular and parvocellular
subnuclei can modulate excitatory and inhibitory receptive fields of tectal cells, respectively, with some interactions between
both fields.
Accepted: 1 March 2000 |
| |
Keywords: | Receptive field Optic tectum Nucleus isthmi Pigeon Visual system |
本文献已被 SpringerLink 等数据库收录! |
|