What are the what and where pathways?

What are the what and where pathways?

In the currently prevailing view, the different maps are organised hierarchically into two major pathways, one involved in recognition and memory (the ventral stream or ‘what’ pathway) and the other in the programming of action (the dorsal stream or ‘where’ pathway).

Where are the dorsal and ventral visual pathways?

The ventral stream originates in primary visual cortex and extends along the ventral surface into the temporal cortex; the dorsal stream also arises in primary visual cortex, but continues along the dorsal surface into parietal cortex.

What is the Where pathway responsible for?

The dorsal stream (or, “where pathway”) leads to the parietal lobe, which is involved with processing the object’s spatial location relative to the viewer and with speech repetition.

What was the Ungerleider and Mishkin experiment?

Ungerleider and Mishkin (1982) identified two processing stream that extend from striate cortex in the occipital lobe to the parietal and temporal lobes. The pathway that extends to the temporal lobe is attributed to be important for identifying objects. So the temporal pathway has been called the “what” pathway.

What is the visual pathway?

The visual pathway refers to the anatomical structures responsible for the conversion of light energy into electrical action potentials that can be interpreted by the brain. It begins at the retina and terminates at the primary visual cortex (with several intercortical tracts).

Where is the ventral pathway?

The ventral pathway was described as coursing through the occipitotemporal cortex to the anterior part of the inferior temporal gyrus (area TE)[1, 2], with a likely extension into the ventrolateral prefrontal cortex (VLPFC/area FDv)[3].

What is the ventral visual pathway?

The ventral visual pathway is a functional stream involved in the visual recognition of objects. The anatomical substrates to the ventral visual pathway were initially identified in macaque monkeys by Mishkin and Ungerleider (1982).

What are the two pathways in the visual system?

Evidence is strong that the visual pathway is segregated into two distinct streams—ventral and dorsal.

Which visual pathway carries information concerning the where of an object?

From the visual cortex, the visual signals travel in two directions. One stream that projects to the parietal lobe, in the side of the brain, carries magnocellular (“where”) information. A second stream projects to the temporal lobe and carries both magnocellular (“where”) and parvocellular (“what”) information.

What is dorsal pathway?

Definition. The dorsal visual pathway is a functional stream originating in primary visual cortex and terminating in the superior parietal lobule that is responsible for the localization of objects in space and for action-oriented behaviors that depend on the perception of space.