Download Document

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
 1st - Strongly involved in the top-down
control of eye movement,
 2nd – 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 longterm 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 TH41.
2. 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.