VISUAL SYSTEM RESEARCH
I am interested in the development of surround inhibition, movement selectivity and their plasticity in the hamster superior colliculus (SC). The hamster visual system is well suited for developmental studies because retinocollicular connections are established during post-natal development. In addition, the hamster SC is a good model for studying recovery from brain trauma. Lesion of the caudal SC within the first 2 days of birth promotes development of the entire visuotopic map in the remaining half. The specific questions are:
1. How doe surround inhibition shape selectivity for the velocity of a moving stimulus in the SC?
2. How does surround inhibition in the SC develop?
Selected Publications
Razak KA and Pallas SL (2007) Inhibitory plasticity facilitates recovery of stimulus velocity tuning in the superior colliculus after chronic NMDA receptor blockade. Journal of Neuroscience 27: 7275-7283 [pdf of article]
Razak KA and Pallas SL. Dark rearing reveals the mechanism underlying stimulus size tuning of superior colliculus neurons. Visual Neuroscience 23:741-748, 2006 [pdf of article]
Razak, KA and Pallas SL (2005) Neural mechanisms of stimulus velocity tuning in the superior colliculus. Journal of Neurophysiology 94:3573–3589 [pdf of article]
Razak KA, Huang L and Pallas SL (2003) Chronic NMDA receptor blockade increases receptive field size without affecting stimulus velocity or size tuning of superior colliculus neurons. Journal of Neurophysiology 90: 110-119.