Spontaneous associative thought may facilitate scene-gist memory via implicit scene-labeling.

Spontaneous associative processes (e.g., mind wandering, spontaneous memory recollection) are prevalent in everyday life, yet their influence on perceptual scene memory is under debate.

Scene-selective brain regions respond to embedded objects of a scene.

Objects are fundamental to scene understanding. Scenes are defined by embedded objects and how we interact with them. Paradoxically, scene processing in the brain is typically discussed in contrast to object processing.

How associative thinking influences scene perception.

Perception of our external environment is not isolated from the influence of our internal thoughts, and past evidence points to a possible common associative mechanism underlying both the perception of scenes and our internal thought. Here, we investigated the nature of the interaction between an associative mindset and scene perception, hypothesizing a functional advantage to an associative thought pattern in the perception of scenes. Experiments 1 and 2 showed that associative thinking facilitates scene perception, which evolved over the course of the experiments.

Contextual associations represented both in neural networks and human behavior.

Contextual associations facilitate object recognition in human vision. However, the role of context in artificial vision remains elusive as does the characteristics that humans use to define context. We investigated whether contextually related objects (bicycle-helmet) are represented more similarly in convolutional neural networks (CNNs) used for image understanding than unrelated objects (bicycle-fork).

Functional Context Affects Scene Processing.

Rapid visual perception is often viewed as a bottom-up process. Category-preferred neural regions are often characterized as automatic, default processing mechanisms for visual inputs of their categorical preference. To explore the sensitivity of such regions to top-down information, we examined three scene-preferring brain regions, the occipital place area (OPA), the parahippocampal place area (PPA), and the retrosplenial complex (RSC), and tested whether the processing of outdoor scenes is influenced by the functional contexts in which they are seen.

Exploring spatiotemporal neural dynamics of the human visual cortex.

The human visual cortex is organized in a hierarchical manner. Although previous evidence supporting this hypothesis has been accumulated, specific details regarding the spatiotemporal information flow remain open. Here we present detailed spatiotemporal correlation profiles of neural activity with low-level and high-level features derived from an eight-layer neural network pretrained for object recognition.

BOLD5000, a public fMRI dataset while viewing 5000 visual images.

Vision science, particularly machine vision, has been revolutionized by introducing large-scale image datasets and statistical learning approaches. Yet, human neuroimaging studies of visual perception still rely on small numbers of images (around 100) due to time-constrained experimental procedures. To apply statistical learning approaches that include neuroscience, the number of images used in neuroimaging must be significantly increased.

Associative hallucinations result from stimulating left ventromedial temporal cortex.

Visual recognition requires connecting perceptual information with contextual information and existing knowledge. The ventromedial temporal cortex (VTC), including the medial fusiform, has been linked with object recognition, paired associate learning, contextual processing, and episodic memory, suggesting that this area may be critical in connecting visual processing, context, knowledge and experience. However, evidence for the link between associative processing, episodic memory, and visual recognition in VTC is currently lacking.

A Neural Basis for Developmental Topographic Disorientation.

Unlabelled: Developmental topographic disorientation (DTD) is a life-long condition in which affected individuals are severely impaired in navigating around their environment. Individuals with DTD have no apparent structural brain damage on conventional imaging and the neural mechanisms underlying DTD are currently unknown. Using functional and diffusion tensor imaging, we present a comprehensive neuroimaging study of an individual, J.

Associative Processing Is Inherent in Scene Perception.

How are complex visual entities such as scenes represented in the human brain? More concretely, along what visual and semantic dimensions are scenes encoded in memory? One hypothesis is that global spatial properties provide a basis for categorizing the neural response patterns arising from scenes. In contrast, non-spatial properties, such as single objects, also account for variance in neural responses. The list of critical scene dimensions has continued to grow--sometimes in a contradictory manner--coming to encompass properties such as geometric layout, big/small, crowded/sparse, and three-dimensionality.

Applying artificial vision models to human scene understanding.

How do we understand the complex patterns of neural responses that underlie scene understanding? Studies of the network of brain regions held to be scene-selective-the parahippocampal/lingual region (PPA), the retrosplenial complex (RSC), and the occipital place area (TOS)-have typically focused on single visual dimensions (e.g., size), rather than the high-dimensional feature space in which scenes are likely to be neurally represented.

Maintaining a cautious state of mind during a recognition test: a large-scale fMRI study.

Decision criterion is an important factor in recognition memory, determining the amount of evidence required to judge an item as previously encountered. For a typical recognition memory test involving the prior study of a set of items, a conservative criterion establishes a higher standard of evidence for recognition and designates fewer items as previously studied. In contrast, a liberal criterion establishes a lower standard of evidence and designates more items as previously studied.

Structurally-constrained relationships between cognitive states in the human brain.

The anatomical connectivity of the human brain supports diverse patterns of correlated neural activity that are thought to underlie cognitive function. In a manner sensitive to underlying structural brain architecture, we examine the extent to which such patterns of correlated activity systematically vary across cognitive states. Anatomical white matter connectivity is compared with functional correlations in neural activity measured via blood oxygen level dependent (BOLD) signals.

The role of the parahippocampal cortex in cognition.

The parahippocampal cortex (PHC) has been associated with many cognitive processes, including visuospatial processing and episodic memory. To characterize the role of PHC in cognition, a framework is required that unifies these disparate processes. An overarching account was proposed whereby the PHC is part of a network of brain regions that processes contextual associations.

Structural foundations of resting-state and task-based functional connectivity in the human brain.

Magnetic resonance imaging enables the noninvasive mapping of both anatomical white matter connectivity and dynamic patterns of neural activity in the human brain. We examine the relationship between the structural properties of white matter streamlines (structural connectivity) and the functional properties of correlations in neural activity (functional connectivity) within 84 healthy human subjects both at rest and during the performance of attention- and memory-demanding tasks. We show that structural properties, including the length, number, and spatial location of white matter streamlines, are indicative of and can be inferred from the strength of resting-state and task-based functional correlations between brain regions.

Individual differences in cognitive style and strategy predict similarities in the patterns of brain activity between individuals.

Neuroimaging is being used increasingly to make inferences about an individual. Yet, those inferences are often confounded by the fact that topographical patterns of task-related brain activity can vary greatly from person to person. This study examined two factors that may contribute to the variability across individuals in a memory retrieval task: individual differences in cognitive style and individual differences in encoding strategy.

Early onset of neural synchronization in the contextual associations network.

Objects are more easily recognized in their typical context. However, is contextual information activated early enough to facilitate the perception of individual objects, or is contextual facilitation caused by postperceptual mechanisms? To elucidate this issue, we first need to study the temporal dynamics and neural interactions associated with contextual processing. Studies have shown that the contextual network consists of the parahippocampal, retrosplenial, and medial prefrontal cortices.

Scenes unseen: the parahippocampal cortex intrinsically subserves contextual associations, not scenes or places per se.

The parahippocampal cortex (PHC) has been implicated in both place/scene processing and episodic memory. We proposed that this region should instead be seen as intrinsically mediating contextual associations and not place/scene processing or episodic memory exclusively. Given that place/scene processing and episodic memory both rely on associations, this modified framework provides a platform for reconciling what seemed like different roles assigned to the same region.

Cultural specificity in amygdala response to fear faces.

The human amygdala robustly activates to fear faces. Heightened response to fear faces is thought to reflect the amygdala's adaptive function as an early warning mechanism. Although culture shapes several facets of emotional and social experience, including how fear is perceived and expressed to others, very little is known about how culture influences neural responses to fear stimuli.

The cortical underpinnings of context-based memory distortion.

Everyday contextual settings create associations that later afford generating predictions about what objects to expect in our environment. The cortical network that takes advantage of such contextual information is proposed to connect the representation of associated objects such that seeing one object (bed) will activate the visual representations of other objects sharing the same context (pillow). Given this proposal, we hypothesized that the cortical activity elicited by seeing a strong contextual object would predict the occurrence of false memories whereby one erroneously "remembers" having seen a new object that is related to a previously presented object.

Famous faces activate contextual associations in the parahippocampal cortex.

The parahippocampal cortex (PHC) has been traditionally implicated both in place processing and in episodic memory. How could the same cortical region mediate these cognitive functions that seem quite different? We have recently proposed that the PHC should be seen as more generally mediating contextual associative processing, which is required for both navigation and memory. We therefore predicted that any associative objects should activate the PHC.

The units of thought.

That associative processing provides the vehicle of thought is a long-standing idea. We describe here observations from cognitive neuroimaging that elucidate the neural processing that mediates this element. This account further allows a more specific ascription of a cognitive function to the brain's "default" activity in mindwandering.

Top-down facilitation of visual object recognition: object-based and context-based contributions.

The neural mechanisms subserving visual recognition are traditionally described in terms of bottom-up analysis, whereby increasingly complex aspects of the visual input are processed along a hierarchical progression of cortical regions. However, the importance of top-down facilitation in successful recognition has been emphasized in recent models and research findings. Here we consider evidence for top-down facilitation of recognition that is triggered by early information about an object, as well as by contextual associations between an object and other objects with which it typically appears.

The parahippocampal cortex mediates spatial and nonspatial associations.

The parahippocampal cortex (PHC) has been implicated in the processing of place-related information. It has also been implicated in episodic memory, even for items that are not related to unique places. How could the same cortical region mediate such seemingly different cognitive processes? Both processes rely on contextual associations, and we therefore propose that the PHC should be viewed not as exclusively dedicated for analyzing place-related information, or as solely processing episodic memories, but instead as more generally playing a central role in contextual associative processing.