Group 2 Youngjin Kang Anthony Correa Stephanie Regan

Parieto-prefrontal Temporal Pathway  LIP (lateral intraparietal) – contains a map of neurons representing the saliency of spatial locations  VIP (ventral intraparietal) – receives input from the senses. Represented space in head-centered reference frame  MT (also known as V5, or middle temporal) is part of the visual cortex. The middle temporal is a region of the visual cortex that is thought to play an important role

 Links the occipito-paritel circuits with two areas, the pre-arcuate region and the caudal portions of the banks of the principal sulcus in the prefrontal cortex  1 st - Strongly involved in the top-down control of eye movement,  2 nd – involved in spatial working memory

Parieto-premotor Pathway  Major source areas  V6A – located at the boundary of the occipital lobe( known to be devoted to visual information) and the parietal lobe. V6A with both visual and motor cortices. The visual input to V6A derives from area V6, a higher order visual area of the dorsomedial visual stream directly connected with the primary visual area V1 [6]. Area V6A is also linked, directly, with the dorsal premotor cortex

 MIP – medial intraparietal – area contains neurons that encode the location of a read target in nose centered coordinates  VIP – ventral intraparietal – receives input from the senses. Represented space in head-centered reference frame  Mediates eye movement, reaching and grasping, other forms of visually guided actions

Function  “For navigating through the environment. The pathway is focused on navigationally relevant information, from distant-space perception and different visuospatial frames of reference through whole-body motion and head direction to route learning and spatial long- term memory” (p. 219)

Pathway  It links the cIPL (which includes areas Opt and PG in FIG. 2) with the MTL — including the hippocampus — through both direct and indirect projections.

1. Direct - One set of efferents runs from the cIPL directly: (1) First, to a small cytoarchitectonic zone located between the subiculum and CA1 (CA1/prosubiculum). (2) Second, to the pre- and parasubicular subdivisions of the hippocampal formation38,39 (see also REFS 40,41). (3) Third, to the posterior parahippocampal areas TF and TH Indirect - there is a set of indirect projections from the same source to the same targets, relayed through a pair of serially connected caudal limbic areas — the PCC (areas 23 and 31) and the RSC (areas 29 and 30)42– 46.

3. Two major outputs of caudal limbic areas (1) To the presubiculum and parasubiculum, the same hippocampal subdivisions that also receive input directly from the cIPL. (2) To the posterior parahippocampal cortex (areas TF, TH and TFO), which projects in turn to the CA1/prosubicular subdivisions of the hippocampus.