Date and time: Friday, 18 March 2022, 17:00-20:00 (JST)

Venue: The symposium will be held online through Zoom (ID/Passcode will be provided to registered participants).

Language: English

Organizer: Tatsuya Yoshizawa (Leader of a research team supported by Kanagawa University Grant for Joint Research)

Co-organizer：Research group ‘Universality and Diversity of Perceptual and Cognitive Systems’ at The Institute for Humanities Research, Kanagawa University

Speakers

• Kojima H. (Kanazawa University)
• Asakura N. (Osaka University)

Program

Abstract

1.Is Chromatic Motion System Lateralized?

Haruyuki KOJIMA (Kanazawa University)

Visual psychologists have long assumed, in general, that our visual sensitivity to the visual world is best at the center in the visual field and concentric to the eccentricity, so that it is not biased either to the right or left of the visual field. However, sometimes, studies have reported a-symmetricities in our visual perception, such as color perception and motion perception. The present talk will introduce our study that have investigated hemispheric sensitivity to chromatic motion perception. A series of experiments examined sensitivities of two visual hemifields for isoluminance points, detection thresholds, and motion thresholds with chromatic or achromatic stimuli. We will discuss our experimental results from the points of view of visual pathway as well as visual perceptual mechanism.

2. A Kalman filter model for adaptation to delayed auditory feedback in adults who stutter

Nobuhiko ASAKURA (Center for Mathematical Modeling and Data Science, Osaka University)

Sensorimotor integration is crucial for efficient speech production, and its dysfunction may be related to the speech disorder of stuttering. Recent evidence shows a stronger effect of adaptation to delayed auditory feedback (DAF) in adults who stutter than in fluent controls. Here, I present a Kalman filter model of DAF adaptation. This model estimates the delay of auditory reafference by optimally combining its prediction with the actual sensory measurement of auditory signals. The model predicts that the effects of DAF adaptation become stronger either when the precision of prediction decreases or when the precision of the measurement increases. Fitting the model to behavioral data reveals that adults who stutter are more imprecise in their prediction of reafferent auditory feedback delays, and that the degree of imprecision is correlated with their stuttering severity.