DrTatjana Seizova-Cajic

Student opportunities

1. Perception of MOTION in touch

This project explores the idea that motion is a major organizing principle for somatosensory and visual maps. Motion across the skin -- or retina -- stimulates locations next to each other in a quick sequence, and those far apart, with a delay. This way, the timing of stimulation of different somatosensory neurons informs about their spatial relations. Motion could thus be critical for development of brain maps. Brain plasticity extends into adulthood and moving stimuli may be able to change maps and space perception in adults. But do they?

We apply unusual patterns of motion to the skin of adult humans and use psychophysics (perceptual tests) to determine if there is a change in their space perception.

2. Filling in of artificial NUMB SPOTS on the skin

A truly numb skin patch can by definition not convey any sensation. We can also create artificial numbness, if we carefully avoid touching one skin patch while repeatedly touching its surround. These artificial numb spots allow us to study how the brain deals with the actual lack of input. We study how they are ‘filled-in’ with sensation in spite of a lack of input – how the brain fills in the gaps.

3. Illusion of SELF-TOUCH

We discovered an illusion of self-touch in which a contact with another person’s fingertips, after several minutes, results in the illusion that we are touching ourselves. This bias toward perceiving self-touch likely occurs because we far more often touch ourselves than others. This projects investigates conditions that favour and impede the illusion, with the aim to better understand cues for self- vs other-touch and laws of tactile perceptual organization.

Potential for collaboration

We would be happy to collaborate with researchers who use high-resolution EEG or fMRI to assess neural correlates of the perceptual phenomena described above.

For example, our self-touch project is concerned with switching between two fundamentally different perceptual states (other-touch vs self-touch) and would be useful for study of their neural correlates. They should be clearly identifiable against other activity because the perceptual switch occurs during complete rest (unchanged bodily posture).