Hippocampal contributions to neurocognitive mapping in humans: A new model

Abstract

The ability of an organism to develop, maintain, and act upon an abstracted internal representation of spatially extensive environments can provide an increased chance in ensuring that organism's survival. Here, we propose a neurocognitive model of spatial representation describing how several different processes interact and segregate the differing types of information used to produce a unified cognitive map. This model proposes that view-based egocentric and vestibulomotor translational information are functionally and anatomically separate, and that these parallel systems result in independent, but interacting, models within a neurocognitive map of space. In this context, we selectively review relevant portions of the large literature, addressing the establishment and operation of such spatial constructs in humans and the brain systems that underpin them, with particular reference to the hippocampal formation (HF). We present a reinterpretation of the types of knowledge used in the formation of this spatial construct, the processes that act upon this information, the nature of the final spatial representation, and describe how these universal concepts relate to the proposed model of spatial processing. The relevant experimental paradigms used to examine the neural basis of spatial representation and the main findings from previous research are also briefly presented. Finally, we detail a series of testable theoretical, behavioral, and anatomical predictions made by the model.

Pedestrian navigation using the sense of touch

“…Spatial strategies can be either egocentric (body-centred) or allocentric (environment-centred), and O' Keefe and Nadel (1978) have suggested that there is a dichotomy between the two (Roche et al, 2005). Learning the layout of an environment can involve strategies such as exploration and search, and in some cases the use of secondary information sources such as maps and photographs can aid the navigator in a novel or unfamiliar environment (Roche et al, 2005).…”

“…Learning the layout of an environment can involve strategies such as exploration and search, and in some cases the use of secondary information sources such as maps and photographs can aid the navigator in a novel or unfamiliar environment (Roche et al, 2005). Two commonly used techniques to learn the layout of the environment are either gaining route-based knowledge or survey-based knowledge.…”

“…Two commonly used techniques to learn the layout of the environment are either gaining route-based knowledge or survey-based knowledge. Route-based knowledge is acquired by physically navigating the environment, an egocentric strategy due to the fact that information is obtained depending on the location of the navigator (Roche et al, 2005). Route-based navigation is based on remembering specific sequences of positions that the person obtains by navigating their environment (Foo, Warren, Duchon, & Tarr, 2005).…”

“…There has been some debate over how humans recall information after navigating environments, with accounts including egocentric and allocentric elements, as well as incorporating route and survey-based information (Roche, Mangaoang, Commins, & O'Mara, 2005). Humans require certain spatial strategies in order to navigate their environment -including a mental representation of the area that they are navigating and the ability to determine a suitable route to explore the environment (Tversky, 2000).…”

Cognitive rehabilitation: assessment and treatment of persistent memory impairments following ECT

“…Assessments of patients who have received ECT do not appear to consider the possibility of such impairments, despite their impact on everyday life. In our work on temporal lobe epilepsy (Mangaoang et al, 2004;Roche et al, 2005), we developed a number of tasks (the Landmark Location, Landmark Recognition and Virtual Map tasks) to measure the ability of patients with left or right unilateral hippocampal damage to recognise photographs of well-known Dublin landmarks and to accurately name their location on a modified map of the city. Patients also described in writing the routes they would take to get from one landmark to another on a map of a virtual city.…”