Yusuke Nakashima

• Ph.D
• Postdoctoral Research Associate at Brown University

Introduction While the social burden of insomnia is substantial, neurochemical mechanisms underlying it are poorly understood. Animal studies suggest the involvement of the medial prefrontal cortex (mPFC) in sleep-wake regulation through glutamatergic and GABAergic signaling. However, the specific roles of these neurotransmitters in human insomnia...

Infant studies have suggested that the detection of biological motion (BM) might be an innate capacity, based on newborns' spontaneous preference for BM. However, it is unclear if, like adults, infants recognize humans from BM and are able to build the representation of bodies and faces. To address this issue, we tested whether exposure to BM influ...

Significance Recent studies in neuroscience suggest that visual perception is not processed by the purely feed-forward system but by the interaction of forward, horizontal, and feedback processing called recurrent loops. The present study examined the development of recurrent processing using visual backward masking, a perceptual phenomenon in whic...

Recurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feedforward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered...

Motion direction of a large high-contrast pattern is more difficult to perceive than that of a small one [1]. This counterintuitive perceptual phenomenon is considered to reflect surround suppression, a receptive field property observed in the visual cortex [2, 3, 4, 5]. Here, we demonstrate that this phenomenon can be observed in human infants. In...

The present study examined whether the Ebbinghaus illusion can be induced by surrounding contexts that are suppressed from conscious perception. We employed continuous flash suppression to render the contextual stimuli invisible. The surrounding contexts were presented to one eye and the masking stimulus was presented to the other eye, followed by...

We used a differential Pavlovian conditioning paradigm to measure tilt aftereffect (TAE) strength. Gabor patches, rotated clockwise and anticlockwise, were used as conditioned stimuli (CSs), one of which (CS+) was followed by the unconditioned stimulus (UCS), whereas the other (CS−) appeared alone. The UCS was an air puff delivered to the left eye....

We investigated whether motion aftereffects (MAE) can be contingent on surroundings. Random dots moving leftward and rightward were presented in alternation. Moving dots were surrounded by an open circle or an open square. After prolonged exposure to these stimuli, MAE were found to be contingent upon the surrounding frames: dots moving in a random...

We investigated whether aftereffects can be contingent on surroundings. Gabor patches tilted clockwise and counterclockwise were presented in alternation. Each patch was surrounded by an open circle or an open square. After prolonged exposure to these stimuli, tilt aftereffects were found to be contingent upon the surrounding frames: Vertical test...