Representational Neglect A Spatial Imagery Deficit

Unilateral neglect is defined as the patient's failure to report, respond to, or orient toward novel and or meaningful stimuli presented to the side opposite to the brain lesion (Heilman et al., 1985 Vallar and Bisiach, 1997). For example, neglect patient can forget to read the left part of a journal or a book omit to eat the left half of a plate or forget to sheave the left hemi-face. This syndrome is frequently consecutive to the damage of the right brain hemisphere. It often is in...

Casimir An Architecture For Mental Spatial Knowledge Processing

In the following, various aspects of our model Casimir (Computational Architecture, Specification and Implementation of Mental Image-based Reasoning) will be presented. The aim of Casimir is to realize a cognitively adequate computational description for mental reasoning processes based on mental images and mental models. Casimir is conceptualized as a comprehensive system including mental processes in long-term memory (LTM) and in working memory (WM), as well as the interaction between mental...

Associative Memories

Associative memory receives input from all of the modality-specific mechanisms that allow us to recognize objects. For example, we can recognize a dog by seeing it, hearing its bark, or petting its fur and once we recognize it, using different what systems, we can identify it, using long-term associative memory. Outputs from the ventral and dorsal pathways converge in long-term associative memory. The mere fact that you can picture where certain items are in your kitchen cabinets is evidence...

Design of Representation Structures for Working Memory Representations

As described above, spatio-analogical representations in working memory (WM) can be either spatial or visual, where the spatial representation is assumed to be constructed first during a reasoning task and may be further processed towards a visual mental image. From the perspective of cognitive economy (Collins and Quillian, 1969), however, it is sensible to assume that a mental representation is only made as specific as necessary with respect to the task to be performed on. Thus, a visual...

Mental Spatial Knowledge Processing

Being an indispensable precondition of any goal-directed behavior of intelligent species in an environment, spatial knowledge processing has received intense attention in cognitive science. Spatial skills rely on mental facilities that go far beyond abstract symbol manipulation (e.g., Huttenlocher, 1968). Mental spatial reasoning capabilities are directly intertwined with perceptual and motor systems (e.g., Barsalou, 1999). Thus, research results in spatial cognition have helped to develop a...

Gross Anatomical Subdivision

The parietal lobe is one of the core regions for spatial processing. This area has undergone a major expansion during human evolution and occupies approximately one fourth of the human brain. It is the region of the cerebral cortex located between the frontal and occipital lobes. On the medial surface this region is roughly demarcated anteriorly by the central sulcus, ventrally by the subparietal sulcus, and posteriorly by the parieto-occipital sulcus. On the lateral surface the parietal lobe...

Lesion Studies In An Era Of Brain Imaging

In a recent issue of the Journal of Cognitive Neuroscience, Anjan Chatterjee noted that, As an example of the present-day peculiarities of conducting lesion studies, in a competitive renewal of a National Institutes of Health grant investigating unilateral spatial neglect, I was asked by a primary reviewer from a cognitive neuroscience study section to 'justify the use of patients to study the topic in question' (p. 849). The implication is that studying cognitive problems in patients with...

Functions Controlled By The Parietal Cortex

Many psychological functions are related to the parietal cortex. Some of them are presented and discussed in this book. In this paragraph I would like to summarize these functions in a broader context. The parietal cortex can be subdivided on a functional basis in at least two parts, the anterior and posterior parietal cortex. The anterior parietal cortex is covered by the postcentral gyrus (Brodmann areas 1, 2, and 3) and the parietal operculum (area subparietalis). Figure 9-4. Schematic...

Of Spatial Cognition And Mental Rotation

Spatial cognition may be defined as the ability to generate, retain, retrieve, and transform well-structured visual images. Spatial ability occupies a pivotal role in all models of human ability. For example, most models of human ability state that together with verbal ability spatial cognition captures more variance than any other dimensions in large, representative batteries of ability tests (Thurstone, 1938). Spatial ability has been measured with various tests such as form boards, block...

The Ventral And Dorsal Systems

Patterns of activity in the visual buffer provide input to two major systems. The ventral system is a set of brain regions running from the occipital lobe through the inferior temporal lobe. The ventral system encodes object properties, such as shape, color, and texture. Some cells in these areas are so highly tuned that they respond to very specific stimuli, such as faces seen in profile. Higher cells in the system (i.e., those further down the processing pathway) have very large receptive...