Dynamics of the functional link between area MT LFPs and motion detection
Jackson E T Smith1, Vincent Beliveau2, Alan Schoen2
1Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom; Department of Physiology, McGill University, Montreal, Quebec, Canada; and.
Journal of Neurophysiology
|May 8, 2015
Summary
Neural signals in the middle temporal area (MT) show distinct timing patterns related to motion perception. Fast high-gamma signals correlate with early perception, while slower beta signals reflect later processing stages.
Area of Science:
- Neuroscience
- Computational Neuroscience
- Systems Neuroscience
Background:
- Perceptual decisions involve complex neural processes.
- Different neural origins are linked to distinct cortical local field potential (LFP) frequency bands.
- Spike activity and LFPs in the middle temporal area (MT) correlate with motion perception.
Purpose of the Study:
- To investigate the temporal dynamics of neural-behavioral correlations between MT spikes and LFPs.
- To differentiate the neural origins underlying the functional link between MT activity and motion perception.
Main Methods:
- Simultaneous wide-band activity recording from two MT locations in monkeys.
- Monkeys performed a threshold, two-stimuli, motion pulse detection task.
- Comparison of temporal dynamics of neural-behavioral correlations for MT spikes and LFPs across different frequency bands (high-gamma, beta).
Main Results:
- High-gamma (100-200 Hz) LFPs showed fast, positive correlation with detection performance shortly after stimulus onset, similar to spike responses.
- Beta (10-30 Hz) LFPs exhibited slower, negative correlation with performance, peaking late and independent of stimulus configuration or reaction time.
- A late change in LFP correlation across electrodes suggested common input to MT locations before the behavioral response.
Conclusions:
- Early high-gamma LFPs likely represent fast, bottom-up sensory processing causally linked to motion pulse perception.
- Late-arriving beta and high-gamma LFPs may reflect slower, top-down neural-behavioral correlations originating after perception.
- This framework distinguishes early sensory processing from later cognitive influences on behavior.
