Vision Dynamics

We study mechanisms underlying the human visual system using functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) as well as psychophysical techniques.  Our experiments focus mainly on understanding of the vision dynamics, such as attention, contextual modulation and filling-in processes.

TOWARDS A PERFORMANCE-ENHANCING INTERFACE

As the mechanisms of attention become better understood, it becomes possible to estimate the direction of attention and preparedness levels of a person by monitoring brain activity. We are furthering research to apply this method by aiming towards constructing a performance-enhancing interface that provides necessary information to the person
“at just the right time, and at just the right place”
.

THE MECHANISMS OF ATTENTION

We measure brain activity that occures when attention is directed to some location of feature,and clarify the mechanisms of attention.

Figure.1 Areas of the brain
that process visual information

1. Study on spatial attending

We have found that when attention is directed to a spatial location, alpha band activity in the corresponding early visual cortex becomes more desynchronized before stimulus presentation than when attention is not directed to the location.

Figure.2

This can be thought of as preparation for the incoming visual stimulus that will eventually be presented. We have also found that the more pronounced this preparatory activity is, the better the subject performs at discriminating the stimulus when it is presented.

Figure.3

2. Study on feature-based attention (color, movement, etc.)

When attention is directed to a feature, like color or motion, the visual areas that process the feature become active before the stimulus is presented. This can also be thought of as preparatory activity for the incoming stimulus presentation.

Figure.4

PEOPLE

<Researchers>

– Noriko Yamagishi
– Matthew DeBrecht
– Okito Yamashita
– Taku Yoshioka
– Yusuke Takeda

<Collaborators>
– Daniel E. Callan
– Stephen J. Anderson (Aston University)
– Takeo Watanabe (Boston University)