The Rapid Extraction of Gist—Early Neural Correlates of High-level Visual Processing

Abstract

Abstract■ The human cognitive system is highly efficient in extracting information from our visual environment. This efficiency is based on acquired knowledge that guides our attention toward relevant events and promotes the recognition of individual objects as they appear in visual scenes. The experience-based representation of such knowledge contains not only information about the individual objects but also about relations between them, such as the typical context in which individual objects co-occur. The present EEG study aimed at exploring the availability of such relational knowledge in the time course of visual scene processing, using oscillatory evoked gammaband responses as a neural correlate for a currently activated cortical stimulus representation. Participants decided whether two simultaneously presented objects were conceptually coherent (e.g., mouse-cheese) or not (e.g., crown-mushroom). We obtained increased evoked gamma-band responses for coherent scenes compared with incoherent scenes beginning as early as 70 msec after stimulus onset within a distributed cortical network, including the right temporal, the right frontal, and the bilateral occipital cortex. This finding provides empirical evidence for the functional importance of evoked oscillatory activity in high-level vision beyond the visual cortex and, thus, gives new insights into the functional relevance of neuronal interactions. It also indicates the very early availability of experience-based knowledge that might be regarded as a fundamental mechanism for the rapid extraction of the gist of a scene. ■

Distributed Patterns of Event-Related Potentials Predict Subsequent Ratings of Abstract Stimulus Attributes

“…We conclude that our analysis was successful in predicting post-experimental time reference ratings from brain activity recorded during passive stimulus viewing, providing evidence that this specific stimulus dimension might be processed automatically, without deliberately directing attention. These findings are in line with reports that the ‘gist’ or general meaning of a scene can be extracted rapidly, as early as 70 ms after exposure to a stimulus [59] , [60] . Moreover, we could predict directly from brain activity the extent to which individuals experienced some very abstract attributes of the stimuli that were not part of the explicitly depicted elements of the image (e.g.…”

Associative recognition processes are modulated by the semantic unitizability of memoranda

“…Ample evidence from the visual perception literature has documented the importance of semantic and spatial object-to-object relations to online unitization or to ''perceptual grouping'' processes (e.g., Auckland, Cave, & Donnelly, 2007;Davenport, 2007;Green & Hummel, 2006;Gronau & Shachar, 2014;Oppermann, Hassler, Jescheniak, & Gruber, 2012;Roberts & Humphreys, 2011). More relevant to the present research, several studies have demonstrated the significance of such unitization processes for visual memory encoding and retrieval processes (e.g., Hollingworth, 2006;Mandler & Parker, 1976;Mandler & Ritchey, 1977).…”

Perceiving the Tree in the Woods: Segregating Brain Responses to Stimuli Constituting Natural Scenes

“…We demonstrated the feasibility of a role for SSVEPs in unraveling the contribution of simultaneous neuronal processes involved in the perception of scenes. Future studies should combine experimental designs that allow the analysis of SSVEPs and of markers of ultrafast categorization processes (Müller and Hillyard, 2000;Oppermann et al, 2011).…”