Time course of the integration of spatial frequency-based information in natural scenes

Abstract

It is known that visual information is processed separately and based on multiple spatial frequencies. Therefore, integration of information is important for categorization of natural scenes. To clarify the time course of visual integration, we examined categorization accuracies for spatially filtered images as a function of image exposure duration. Results indicated that, with image durations of 100-ms, accuracy was superior with spatially integrable images when compared with accuracy levels based upon the probability summation model estimated from accuracies of separately presented low- and high-frequency images. This finding suggests that spatial frequency integration begins earlier than 100-ms after the image onset.

The effects of display time and eccentricity on the detection of amplitude and phase degradations in textured stimuli

“…The time courses of frequency and phase processing have both previously been studied independently, using different stimuli and tasks (Kihara & Takeda, 2010;Rousselet et al, 2008). Evidence from those studies suggested that phase spectrum information is available for visual tasks with a delay of approximately 40 ms after amplitude spectrum information becomes available.…”

“…Kihara and Takeda (2010) investigated the time course of this process in an experiment that used a natural image categorization task. They found an advantage for composite low-and high-pass filtered stimuli over probability summation of separate filtered images between 83 and 100 ms after stimulus onset, implying that integration of channel outputs has begun by this time.…”

“…Rousselet, Pernet, Bennett, and Sekuler (2008) investigated how early eventrelated potentials (ERPs) to images of faces are affected by the addition of phase noise and found that sensitivity to phase noise starts at around 120-130 ms. This is slightly longer than the time needed to integrate information from multiple frequencies (Kihara & Takeda, 2010). However, very different stimuli and experimental procedures were used in the two experiments.…”

Modulation of microsaccades by spatial frequency during object categorization

“…Importantly, the 83 categorization of LSF-only objects outperformed the categorization of HSF objects for the 84 exposure durations of up to 250 ms, suggesting a prior for LSF information in early 85 processing in this kind of categorization task (Kihara & Takeda, 2010). The differences did 86 not change when attentional demands were increased, suggesting that the effects are based on 87 the first feedforward processing (Kihara & Takeda, 2012).…”

“…Spatial frequency information at different scales contributes to object categorization from around 100 ms of exposure duration (Kihara & Takeda, 2010, 2012. Importantly, the 83 categorization of LSF-only objects outperformed the categorization of HSF objects for the 84 exposure durations of up to 250 ms, suggesting a prior for LSF information in early 85 processing in this kind of categorization task (Kihara & Takeda, 2010).…”