1 / 8

The role of gamma oscillations in perceptual binding and scene analysis.

The role of gamma oscillations in perceptual binding and scene analysis. Andy Dykstra HST.722 November 1, 2007. Perceptual Binding?. Objects have features However, we perceive them as whole entities

sevita
Download Presentation

The role of gamma oscillations in perceptual binding and scene analysis.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The role of gamma oscillations in perceptual binding and scene analysis. Andy Dykstra HST.722 November 1, 2007

  2. Perceptual Binding? • Objects have features • However, we perceive them as whole entities • How does one associate the various features with each other to form the representation of the object? • How does one assign features to objects when multiple objects are present? • How do different neuronal patterns, each representing a feature, “bind” together to bring about unified percepts and meaningful action? Von der Malsburg (1981), Roskies (1999), Tallon-Baudry and Bertrand (1999)

  3. 30 – 80 Hz fluctuations in neuronal signals measured at varying levels (units, local field potentils, EEG, MEG) Three types: Steady-state response Evoked (synchronized with stimulus) Induced (brought about by stimulus, but not synchronous with stimulus) Epiphenomena or fundamental role in perception and cognition? Gamma Oscillations? Gray (1994), Buzsáki (2006), Buzsáki and Draguhn (2004), Tallon-Baudry and Bertrand (1999)

  4. Are they related? • Gamma oscillations may provide mechanism of synchronizing neuronal populations representing different features • This, when observed, could bind features

  5. Joilot et al. (1994) Evoked responses @ ~40Hz track perception of one or two clicks Results from the Auditory System.

  6. Results from the Auditory System. • Ross et al. (2005) • Stimulus induced reset of 40-Hz ASSR

  7. Results from the Auditory System. • Lakatos et al. (2005) • Hierarchy of oscillatory activity in primary auditory cortex • Delta (1-4Hz) modulates theta (4-10Hz), which modulates gamma (30-50Hz) • Suggests that auditory cortex is optimized to process rhythmic inputs and provides possible mechanism for rhythmic expectation

  8. Questions?

More Related