Linked Life Data

10463791

Source:http://linkedlifedata.com/resource/pubmed/id/10463791

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-10-8
pubmed:abstractText
Xenopus frogs exhibit dramatic changes in the binocular projections to the tectum during a critical period of development. Their eyes change position in the head, moving from lateral to dorsal and creating an increasing region of binocular overlap. There is a corresponding shift of binocular projections to the tectum that keeps the two eyes' maps in register with each other throughout this period. The ipsilateral input is relayed via the nucleus isthmi. Two factors bring the ipsilateral projection into register with the contralateral projection. First, chemoaffinity cues establish a crude topographic map beginning when the shift of eye position begins. Approximately 1 month later, visual cues bring the ipsilateral map into register with the contralateral map. The role of visual input is demonstrated by the ability of the axons that bring the ipsilateral eye's map to the tectum to reorganize in response to a surgical rotation of one eye and to come into register with the contralateral eye's map. This plasticity can be blocked by NMDA receptor antagonists during the critical period. In normal adults, reorganization is minimal. Eye rotation fails to induce reorganization of the ipsilateral map. However, plasticity persists indefinitely in animals that are reared in the dark, and plasticity can be restored in normally-reared animals by treatment with NMDA. The working model to explain this plasticity posits that correlated input from the two eyes triggers opening of NMDA receptor channels and initiates events that stabilize appropriately-located isthmotectal connections. Specific tests of this model are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0301-0082
pubmed:author
pubmed:issnType
Print
pubmed:volume
59
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
81-106
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Plasticity in the tectum of Xenopus laevis: binocular maps.
pubmed:affiliation
Department of Physiology and Biophysics, State University of New York, Buffalo 14214, USA. sudin@buffalo.edu
pubmed:publicationType
Journal Article, Review