Dynamic properties of internal noise probed by modulating binocular rivalry

Area of Science:

• Neuroscience
• Computational Neuroscience
• Perceptual Psychology

Background:

• Neural systems exhibit inherent noise, influencing moment-to-moment perception.
• Binocular rivalry demonstrates this noise effect, with alternating perception of competing visual stimuli.
• Understanding internal noise dynamics is crucial for explaining perceptual variability.

Purpose of the Study:

• To investigate the impact of external noise modulation on perceptual consistency during binocular rivalry.
• To characterize the temporal properties of internal noise in the human visual system.
• To develop and validate a computational model of binocular rivalry incorporating internal noise.

Main Methods:

• Modulating rivaling stimuli with dynamic sequences of external noise at various rates and amplitudes.
• Assessing perceptual consistency by repeating noise sequences and analyzing percept stability.
• Employing a computational model with a 1/f temporal amplitude spectrum for internal noise.

Main Results:

• External noise modulations, particularly at higher contrasts and 1/8Hz, significantly increased perceptual consistency.
• The computational model with a 1/f internal noise spectrum and 16% standard deviation best explained the experimental data.
• The study successfully estimated dynamic properties of internal noise during binocular rivalry.

Conclusions:

• External noise can be leveraged to probe and modulate internal noise processes in the visual system.
• Internal noise in binocular rivalry exhibits pink noise characteristics (1/f spectrum).
• This research offers a novel technique for estimating internal noise dynamics, applicable to perception and spontaneous brain activity.