Sensitivity to spectrotemporal modulations is critical for speech perception, yet how cortical representations of these modulations adapt to cognitive goals remains unclear. Using EEG in human listeners, we examined how task demands shape spectrotemporal encoding during speech perception under controlled background noise. Participants engaged in either a comprehension or detection task using identical speech stimuli, allowing us to isolate top-down effects on auditory processing of speech modulations. We developed the Modulation Response Function (MRF), a novel analysis method that reconstructs cortical sensitivity to spectrotemporal features. While both tasks elicited robust neural encoding, spectrotemporal tuning profiles diverged: comprehension selectively enhanced cortical sensitivity to formant-related modulations, whereas detection amplified pitch-related modulations. These task-specific patterns emerged despite identical sensory input, highlighting a flexible, goal-driven reshaping of spectrotemporal representation in auditory cortex. These findings provide evidence of a flexible regime of encoding spectrotemporal modulations in service of difference cognitive tasks in order to support speech perception in challenging environments.
Huet et al. (Wed,) studied this question.