Attention rhythmically samples multi-feature objects in working memory

Abstract

Attention allows us to selectively enhance processing of specific locations or features in our external environment while filtering out irrelevant information. It is currently hypothesized that this is achieved through boosting of relevant sensory signals which biases the competition between neural representations. Recent neurophysiological and behavioral studies revealed that attention is a fundamentally rhythmic process, tightly linked to neural oscillations in frontoparietal networks. Instead of continuously highlighting a single object or location, attention rhythmically alternates between multiple relevant representations at a frequency of 3–8 Hz. However, attention cannot only be directed towards the external world but also towards internal visual working memory (VWM) representations, e.g. when selecting one of several search templates to find corresponding objects in the external world. Two recent studies demonstrate that single-feature objects in VWM are attended in a similar rhythmic fashion as perceived objects. Here we add to the literature by showing that non-spatial retro-cues initiate comparable theta-rhythmic sampling of multi-feature objects in VWM. Our findings add to the converging body of evidence that external and internal visual representations are accessed by similar rhythmic attentional mechanisms and present a potential solution to the binding problem in working memory.

Behavioral fluctuation reflecting theta-rhythmic activation of sequential working memory

“…Conversely, detailed observation of our behavioral index (i.e., reaction time, RT) in tasks that require participants to recall sequential information would reveal temporal uctuation of neural activity realizing sequential working memory. Such behavioral uctuations have been reported in the eld of attention (Fiebelkorn et al, 2013;Helfrich et al, 2018;Landau & Fries, 2012;VanRullen, 2018) and working memory (Abdalaziz et al, 2023;Chota et al, 2022;Peters et al, 2021;Pomper & Ansorge, 2021). For instance, it was reported that the reaction time and detection rate for a stimulus in a location showed uctuation in the theta range, showing that even "sustained" attention is not stable but uctuates (Fiebelkorn et al, 2013;Helfrich et al, 2018).…”

Microsaccades track location-based object rehearsal in visual working memory

“…Accordingly, our microsaccade observations may signal serial refreshing by the oculomotor system that may serve as a mechanism supporting object maintenance. In future studies, it will be interesting to address whether and how these microsaccade findings relate to recent complementary findings of serial object-sampling in working memory (e.g., Chota et al, 2022; Peters et al, 2021; Pomper & Ansorge, 2021).…”

Periodic neglect after frontoparietal lesions provides causal evidence for rhythmic attention sampling

“…Recently, similar observations have been made for object- 10 and feature-based 38 attention as well as abstract cue-guided visual perception 12 . It might also apply to related cognitive concepts, such as working-memory 39 or other sensory domains, such as audition 40 . Several lines of inquiry suggested that rhythmic brain activity in the frontoparietal attention network constitutes a viable mechanism that efficiently segregates attentional sampling from attentional shifting, i.e., separates sensory from motor functions 2 .…”