The surface side of the body oriented upwards, away from the pull of gravity, is the Dorsal side. The opposite side, typically the one closest to the ground when walking on all legs, swimming or flying, is the Ventral side. For example: the spine is located on the dorsal side, a sharks Dorsal Fin is well known and a cow's udder is on the Ventral side.

Visual information is transmitted from V1 via two streams
A. Dorsal stream :

• "Where" pathway
  
• Location and movement for action
• Unconscious pathway
• Receives mostly magnocellular input
• Projects to post. parietal association cortex

B. Ventral stream :

• "What" pathway
• Object recognition / analysis of form
• Conscious pathway
  
• Receives an equal mix of magnocellular and parvocellular input
  
• Projects to extrastriate cortex (V2, V3, V4, V5) and to inferior temporal cortex (TEO, TE, STS)

A. The dorsal stream is involved in spatial awareness: recognizing where objects are in space, and guidance of actions i.e. reaching.

• Detailed map of the visual field.
• Accurate body image.

• Perception and interpretation of spatial relationships.
• Detecting and analysing movements.
• Learning of tasks involving coordination of the body in space

It starts in V1 with purely visual functions and gradually transfers to spatial awareness at its termination in the Posterior Parietal Cortex (PPC),

• LIP area: Produces enhanced activation when attention is moved onto the stimulus.

• VIP area: Integrates visual and somatosensory information.

B. The ventral stream is associated with object recognition and form representation. All it's areas are influenced by extraretinal factors in addition to the nature of the stimulus in their receptive field. These factors include:

• Attention
• Working memory
• Stimulus salience

Each visual area contains a full representation of visual space, it contains neurons whose receptive fields together represent the entire visual field, and it has strong connections to:

• Medial temporal lobe: stores long-term memories
• Limbic system: controls emotions
• Dorsal stream: deals with object locations and motion

It starts in V1 and travels through V2 - V4 to the Inferior Temporal Lope (ITL).

• PIT (posterior inferotemporal)
• CIT (central inferotemporal)
• AIT (anterior inferotemporal)

The ventral stream does not merely provide a description of the elements in the visual world, it also plays a crucial role in judging the significance of these elements.