Effects of "temporal preparation" on neural processing of physical and affective material attributes

It remains unclear whether different material attributes, such as glossiness and aesthetics, rely on different stages of visual processing. This study investigated how "temporal preparation," defined here as participants' expectation of stimulus duration, modulates the neural dynamics of material perception, thereby helping reveal the underlying processing stages. Electroencephalography (EEG) was recorded while participants viewed images of various objects and made judgments of either glossiness or aesthetic value. Temporal preparation was manipulated by changing the ratio of short (100 ms) to long (1000 ms) stimulus presentations within each session. This manipulation was intended to alter participants' expectations of stimulus duration without directly constraining the actual presentation duration. Decoding analyses were used to classify binary perceptual judgments from the EEG signals. The results showed that expectations of shorter durations enhanced decoding accuracy for glossiness, whereas expectations of longer stimulus durations tended to enhance decoding accuracy for aesthetics. These findings suggest that temporal preparation influences neural representations differently depending on the material attribute. This approach provides a useful methodological framework for dissociating perceptual strategies and offers new insights into the temporal dynamics of different material impressions.