Browsing by Subject "RSC"

Now showing 1 - 3 of 3

Open Access
Functional subdomains within scene-selective cortex: parahippocampal place area, retrosplenial complex, and occipital place area
(Society for Neuroscience, 2016) Çukur, Tolga; Huth, A. G.; Nishimoto, S.; Gallant, J. L.
Functional MRI studies suggest that at least three brain regions in human visual cortex-the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA; often called the transverse occipital sulcus)-represent large-scale information in natural scenes. Tuning of voxels within each region is often assumed to be functionally homogeneous. To test this assumption, we recorded blood oxygenation level-dependent responses during passive viewing of complex natural movies. We then used a voxelwise modeling framework to estimate voxelwise category tuning profiles within each scene-selective region. In all three regions, cluster analysis of the voxelwise tuning profiles reveals two functional subdomains that differ primarily in their responses to animals, man-made objects, social communication, and movement. Thus, the conventional functional definitions of the PPA, RSC, and OPA appear to be too coarse. One attractive hypothesis is that this consistent functional subdivision of scene-selective regions is a reflection of an underlying anatomical organization into two separate processing streams, one selectively biased toward static stimuli and one biased toward dynamic stimuli.
Open Access
Perception of built environments and its neural modulation by the behavioral goals of the perceiver
(2023-07) Koç, Aysu Nur
A scene is a view of an environment with a spatial layout one can act within. Scene perception has been studied extensively in the neuroscience literature, examining changes in neural activity across the brain and scene-selective regions (PPA, RSC, OPA), in response to various low and high-level features and tasks. The focus of the field has been mostly on outdoor scenes based on broad categorical differences (e.g. natural/man-made) or basic differences between otherwise similar indoor environments (e.g. ceiling height) and behavioral components regarding scene perception have been overlooked. Interactions with fields such as environ-mental psychology or neuroarchitecture, which could inspire a more ecologically valid study of scenes, are rare. Hereby, we investigated the perception of built environments where we spend most of our time, drew our categorization method from the architecture literature, and employed multiple tasks. The categories were elements that (i) allow our access to and circulation within environments (entrances, exits, corridors, stairs); and that (ii) do not directly aid locomotion but rather serve human needs (restrooms, eating and seating areas). FMRI scans were obtained from 23 participants as they viewed scenes from built environments and performed two tasks: a categorization task based on the main afforded action differences between the defined categories, and an approach-avoidance task where participants decided to enter the scene or not, measuring the initial action regarding an environment. Scene-selective ROIs were defined with a localizer session. Univariate analyses did not reveal strong differences between the tasks. Searchlight MVPA revealed categories, but not tasks, are classified at the whole-brain level, at the lingual and parahippocampal gyri, the SMA, and the occipital cortex. Model-based RSA at the ROI level revealed that tasks modulate activation patterns to built environments in all three ROIs, but do not entirely explain them, whereas categorical and visual models did not correlate with the activation patterns in any of these regions. We utilize an interdisciplinary perspective to scene perception to expand the ecological validity of the stimuli and task con-tent, showing that neural responses to built environments are modulated by the behavioral goals of the observer at the ROI level, and stimulus category at the whole-brain level.
Open Access
Task-modulated neural responses in scene-selective regions of the human brain
(Elsevier Ltd, 2025-02) Koç, Aysu Nur; Ürgen, Burcu Ayşen; Afacan, Yasemin
The study of scene perception is crucial to the understanding of how one interprets and interacts with their environment, and how the environment impacts various cognitive functions. The literature so far has mainly focused on the impact of low-level and categorical properties of scenes and how they are represented in the scene-selective regions in the brain, PPA, RSC, and OPA. However, higher-level scene perception and the impact of behavioral goals is a developing research area. Moreover, the selection of the stimuli has not been systematic and mainly focused on outdoor environments. In this fMRI experiment, we adopted multiple behavioral tasks, selected real-life indoor stimuli with a systematic categorization approach, and used various multivariate analysis techniques to explain the neural modulation of scene perception in the scene-selective regions of the human brain. Participants (N = 21) performed categorization and approach-avoidance tasks during fMRI scans while they were viewing scenes from built environment categories based on different affordances ((i)access and (ii)circulation elements, (iii)restrooms and (iv)eating/seating areas). ROI-based classification analysis revealed that the OPA was significantly successful in decoding scene category regardless of the task, and that the task condition affected category decoding performances of all the scene-selective regions. Model-based representational similarity analysis (RSA) revealed that the activity patterns in scene-selective regions are best explained by task. These results contribute to the literature by extending the task and stimulus content of scene perception research, and uncovering the impact of behavioral goals on the scene-selective regions of the brain.