The Sprague effect is the phenomenon where homonymous hemianopia, caused by damage to the visual cortex, gets slightly better when the contralesional superior colliculus is destroyed.[1][2] The effect is named for its discoverer, James Sprague, who observed this phenomenon in 1966 using a cat model.[3] Several reasons have been thought of for this happening, including mutual inhibition between the two brain hemispheres.[4] For similar reasons of inhibiting an inhibitory structure, damaging the substantia nigra, for instance by using ibotenic acid, can also cause the same improvement.[5]
References edit
- ^ Weddell, Rodger A. (August 2004). "Subcortical modulation of spatial attention including evidence that the Sprague effect extends to man". Brain and Cognition. 55 (3): 497–506. doi:10.1016/j.bandc.2004.02.075. PMID 15223196.
- ^ Lomber, Stephen G.; Malhotra, Shveta; Sprague, James M. (2007-02-01). "Restoration of Acoustic Orienting Into a Cortically Deaf Hemifield by Reversible Deactivation of the Contralesional Superior Colliculus: The Acoustic "Sprague Effect"". Journal of Neurophysiology. 97 (2). United States: Journal of Applied Physiology: 979–993. doi:10.1152/jn.00767.2006. PMID 17151228.
- ^ Sprague, James M. (1966-09-23). "Interaction of Cortex and Superior Colliculus in Mediation of Visually Guided Behavior in the Cat". Science. 153 (3743): 1544–1547. doi:10.1126/science.153.3743.1544. PMID 5917786.
- ^ Hilgetag, Claus C. (2000-06-01). "Spatial neglect and paradoxical lesion effects in the cat — A model based on midbrain connectivity". Neurocomputing. 32–33. ScienceDirect: 793–799. doi:10.1016/S0925-2312(00)00246-0.
- ^ Wallace, Steven F.; Rosenquist, Alan C.; Sprague, James M. (1990). "Ibotenic acid lesions of the lateral substantia nigra restore visual orientation behavior in the hemianopic cat". The Journal of Comparative Neurology. 296 (2). Wiley-Blackwell: 222–252. doi:10.1002/cne.902960204.