Separating sensory from timing processes: a cognitive encoding and neural decoding approach

The internal clock is a psychological model for timing behavior. According to information theory, psychological time might be a manifestation of information flow during sensory processing. Herein, we tested three hypotheses: (1) whether sensory adaptation reduces (or novelty increases) the rate of the internal clock (2) whether the speed of the clock reflects the amount of cortical sensory processing? (3) whether motion tunes clock speed.

The current study used an oddball paradigm in which participants detected duration changes while being recorded with electroencephalography (EEG). For data analysis, we combined cognitive modeling with neural decoding techniques. Specifically, we designed Adaptive-Thought-of-Control (ACT-R) models to explain human data and linked them to the sensory EEG features discovered through machine learning.

Our results indicate that timing performance is influenced by both timing and non-timing factors. The internal clock may reflect the amount of sensory processing, thereby clarifying a long-standing sensory timing mystery.