The Processing Of Configural Superiority Effect In The Ventral Visual Pathway:A FMRI And TMS Study

Wertheimer,one of the founders of Gestalt psychology,emphasized that our perception is organized in a way to segregate objects from their background.This shows that object formation is an important goal of perceptual organization.However,in the study of perceptual organization,the importance of object formation is ignored.An important phenomenon in perceptual organization is the structural superiority effect(CSE): When the whole of the figure has structural advantages,the recognition of the whole should take priority over the recognition of the part of the figure.So why is CSE effective in visual perception? Considering the importance of object formation in perceptual organization,we propose that the purpose of CSE is to facilitate the formation of perceptual objects.Therefore,when the object is not formed,the configural superiority will no longer be effective.Since the 1970 s,there have been many experiments to study the phenomenon of CSE,but the research on the neural mechanism of this phenomenon is very limited,especially the neural coding of CSE in visually relevant brain regions has not yet been fully understood.Studies have shown that,compared to the early visual cortex(EVC),higher-level visual cortex,such as Lateral occipital complex(LOC),plays a key role in the treatment of CSE.But is this area necessary for the formation of configural superiority effects in the brain? Is the handling of configural superiority only relevant to the region? There is no evidence to explain in previous studies.Therefore,more in-depth research and discussion are needed.Therefore,this article focuses on: 1.The importance of object formation for CSE;2.The neural mechanism of CSE.In order to control the formation of objects,this article uses random-dot stereograms to form objects and non-objects(holes)to study the impact of object formation on CSE;using functional magnetic resonance imaging(fMRI)and transcranial magnetic stimulation(TMS)to explore the processing of configural superiority effects in the ventral visual pathway.First,through behavioral experiments,three sets of behavioral experiments were conducted using the three-dimensional visual stimulus formed by binocular parallax to verify our hypothesis:CSE is only valid for objects,but not holes.Then,the whole brain imaging data under the task state was collected by fMRI,the brain area activation under the task wasanalyzed,and the EVC and LOC brain areas in the ventral visual pathway are analyzed in more detail of ROI to further explore the key brain area for processing CSE.Combined with previous studies and the activation of brain regions in this article by magnetic resonance,three brain regions: left lateral occipital complex(LOC_L),right lateral occipital complex(LOC_R)and left anterior temporal lobe(ATL_L)were selected as stimulation target points for subsequent TMS experiments.The behavioral results of the subjects were analyzed to explore the role of these three brain regions in the configural superiority effect.Both the three sets of behavioral experiments and the results of behavioral experiments in magnetic resonance showed that only when the object was formed there is the configural superiority effect,which verifieds our hypothesis.MRI brain activation results showed that when performing configural superiority effect tasks,LOC had a large activation,which was consistent with previous studies.The subsequent univariate and multivariate results showed that the processing of configural superiority effects was not completed by a specific brain area,but by the joint processing of multiple brain areas.It was also found that EVC can be activated by any stimulus,while LOC can only be activated by certain shapes or objects.Subsequent TMS experiments did not produce significant results,but some trends could be found in the analysis.Stimulating LOC will affect human response to structural superiority effects.More accurate damage studies require further experiments to confirm.