“Selective blockade of the neural pathway related to the visuomotor translation in non-human primates”

Optogenetics enables us to manipulate neural activities in millisecond order. This technique allows us to reveal not only correlation but also causality between a neural circuit and its function. The usability of the optogenetics has been demonstrated mainly in the small model animals such as mice. In the big brain animals such as non-human primates, however, applied studies of the optogenetics are still not so many. In this study, I’ll apply this technique for the study of visual responses in the superior colliculus (SC) of macaque monkeys to investigate its function for the visuomotor transformation.
It is known that the neurons in the superficial layer of SC respond to visual stimuli and this visual response is enhanced if an animal makes saccade toward the visual target. Because of such properties, it is suggested that neurons in the superficial layer of SC are involved in the neural mechanism for visuomotor translation. SC neurons receive visual information both directly from the retina and via primary visual cortex (V1). However, it is not clear which visual pathway is important for the visual response in the superficial SC. In this study, I will introduce the opsin, which elicits hyperpolarization, into V1 by using viral vectors. To selective block of the V1-SC pathway, I will illuminate the axon terminals projecting from V1 via an optical fiber placed on SC. Under such selective blockade, I will test the visual responses of the superficial SC neurons and reveal the dependency of the visual response on this pathway to get insight into the visuomotor translation function in SC.

 

 
Recent Publications
1. Kinoshita M, Matsui R, Kato S, Hasegawa T, Kasahara H, Isa K, Watakabe A, Yamamori T, Nishimura, Y, Alstermark B, Watanabe D, Kobayashi K, Isa T. (2012) Genetic dissection of the circuit for hand dexterity in primates. Nature 487:235-238.
2. Isa T, Kinoshita M, Nishimura Y. (2013) Role of Direct vs. Indirect Pathways from the Motor Cortex to Spinal Motoneurons in the Control of Hand Dexterity. Frontiers in Neurology 4: 191
3. Thongchai S, Isa K, Matsui R, Kato S, Kinoshita M, Kobayashi K, Watanabe D, Kobayashi K, Isa T. (2013) Viral vector-mediated selective and reversible blockade of the pathway for visual orienting in mice. Frontiers in Neural Circuits 7, 162
4. Watakabe A, Ohtsuka M, Kinoshita M, Takaji M, Isa K, Mizukami H, Ozawa K, Isa T, Yamamori T. (2015) Comparative analyses of adeno-associated viral vector serotypes 1, 2, 5, 8 and 9 in marmoset, mouse and macaque cerebral cortex. Neuroscience research 93, 144-57.

Posted:2016/03/10