Research

Our research aims to examine the dynamic/adaptive nature of human visual perception – including its cross-modal, sensory-motor, developmental, decision making, and neurological aspects – using methods having a broad scope. Methodologically, several techniques have been particularly successful, as indicated below.

(1) Microscopic psychophysics of visual perception in a very brief time period (1-200 ms) has revealed how the visual system identifies transient visual input in the context of a sustained, or continuously changing, frame of reference. Our exploration of the "flash lag effect" in motion perception is an example; another example is about the “postdictive” aspect of apparent motion.

(2) Utilizing our new technique combining transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) and psychophysics, we have isolated the exact spatio-temporal details of the visual cortical processes which are directly responsible for various phenomenological aspects of visual perception.

(3) We explore a variety of non-invasive techniques to modulate neural activity in the alert, adult, human subjects, including the TMS and the tDCS which are mentioned above. The other techniques include fMRI- or EEG-based neural feedback.

(4) Various effects in the domain of cross-modal integration have been intensively studied. The auditory-visual effects include; the double flash, the stream/bounce, the crossmodal chronostasis, and the simultaneity adaptation effects. Also, we investigate crossmodal plasticity of the brain by a visual prosthetics device.

(5) Using fMRI, we investigate neural correlates of reward-based decision making and learning.

(6)  Behavioral and neural aspects of visual attractiveness/ preference decision have been studied. Our latest findings include the “gaze cascade” effect (that is, an implicit gaze bias precedes conscious preference decision), the segregation of Novelty and Familiarity principles across object categories, the implicit leakage of visual attractiveness from neglected to attended objects, etc.

(7) We investigate neural correlates of implicit social interactions, utilizing the interpersonal, hyperscan (EEG) system.

Our projects include:

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