Dynamics of history-dependent perceptual judgment

Area of Science:

• Neuroscience
• Sensory Perception
• Computational Modeling

Background:

• Perception is not solely determined by current sensory input.
• The influence of prior stimuli on subsequent judgments is a key aspect of sensory processing.

Purpose of the Study:

• To investigate the role of stimulus history in tactile perception.
• To quantify the impact of past vibrissal vibrations on current judgments of stimulus strength.

Main Methods:

• Rats performed a tactile discrimination task involving vibrissal vibrations.
• Behavioral data were analyzed to identify history-dependent effects.
• A computational model was developed to explain the observed effects.
• Human subjects were tested with fingertip vibrations to assess cross-species generalizability.

Main Results:

• A repulsive stimulus history effect was observed: prior low-speed stimuli increased 'strong' judgments, while high-speed stimuli increased 'weak' judgments.
• This effect decayed exponentially over preceding trials but strengthened with longer inter-trial intervals.
• Human participants exhibited similar history-dependent perception.

Conclusions:

• Sensory history significantly modulates tactile perception in a repulsive manner.
• A single-parameter model successfully captures the dynamics of this history effect.
• This work provides insights into the neural mechanisms underlying how past experiences shape ongoing subjective perception.