1.4 Dorsal and ventral visual streams

Visual processing in the brain involves two key pathways: the dorsal and ventral streams. These streams work together to help us perceive and interact with our visual world, playing crucial roles in art creation and appreciation.

The dorsal stream handles spatial information, helping us locate objects and interact with them. The ventral stream processes object identity, enabling recognition of shapes, colors, and faces. Understanding these pathways sheds light on how we perceive and create art.

Dorsal and ventral streams

• The dorsal and ventral streams are two major pathways in the visual processing system of the brain that process different aspects of visual information
• These streams are crucial for perceiving and interacting with the visual world, including creating and appreciating art
• Understanding the functions and interactions of these streams can provide insights into how the brain processes visual information and how this relates to artistic abilities and experiences

Visual processing pathways

Dorsal "where" pathway

Top images from around the web for Dorsal "where" pathway

• 

  Magnocellular and Parvocellular pathways – Introduction to Sensation and Perception View original

  Is this image relevant?

• 

  Frontiers | Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and ... View original

  Is this image relevant?

• 

  Module 21: Visual System – Anatomy 337 eReader View original

  Is this image relevant?

• 

  Magnocellular and Parvocellular pathways – Introduction to Sensation and Perception View original

  Is this image relevant?

• 

  Frontiers | Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and ... View original

  Is this image relevant?

1 of 3

Top images from around the web for Dorsal "where" pathway

• 

  Magnocellular and Parvocellular pathways – Introduction to Sensation and Perception View original

  Is this image relevant?

• 

  Frontiers | Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and ... View original

  Is this image relevant?

• 

  Module 21: Visual System – Anatomy 337 eReader View original

  Is this image relevant?

• 

  Magnocellular and Parvocellular pathways – Introduction to Sensation and Perception View original

  Is this image relevant?

• 

  Frontiers | Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and ... View original

  Is this image relevant?

1 of 3

• Processes spatial information about the location, motion, and depth of objects in the visual field
• Enables the perception of where objects are in space and how to interact with them (reaching, grasping)
• Extends from the primary visual cortex to the parietal lobe

Ventral "what" pathway

• Processes information about the identity, color, and form of objects in the visual field
• Enables the recognition and identification of objects, faces, and scenes
• Extends from the primary visual cortex to the temporal lobe

Anatomy of streams

Origins in primary visual cortex

• Both streams originate in the primary visual cortex (V1) in the occipital lobe
• V1 receives input from the lateral geniculate nucleus of the thalamus and performs early visual processing (edge detection, orientation selectivity)
• From V1, visual information is split into the dorsal and ventral streams for further processing

Dorsal stream structures

• Includes areas V2, V3, V5/MT (middle temporal), and regions in the parietal lobe (intraparietal sulcus, superior parietal lobule)
• These areas are involved in processing motion, depth, and spatial relationships between objects
• The parietal lobe integrates visual information with proprioceptive and motor information for visuomotor coordination

Ventral stream structures

• Includes areas V2, V4, and regions in the temporal lobe (inferotemporal cortex, fusiform gyrus)
• These areas are involved in processing color, form, and object identity
• The inferotemporal cortex contains neurons that respond selectively to complex visual stimuli (faces, objects, scenes)

Functions of streams

Dorsal stream: spatial processing

• Processes the location and motion of objects in space, enabling the perception of where things are and how they are moving
• Involved in the coordination of visual information with motor actions (reaching, grasping, eye movements)
• Enables the perception of depth and distance, which is crucial for interacting with the environment and creating realistic art

Ventral stream: object recognition

• Processes the identity and features of objects, enabling the recognition and categorization of visual stimuli
• Involved in the perception of color, form, and texture, which are important for identifying and discriminating between objects
• Enables the recognition of faces, which is crucial for social interactions and portraiture in art

Interactions between streams

Interconnections and feedback loops

• The dorsal and ventral streams are not entirely separate but have interconnections and feedback loops that allow for the integration of information
• Areas in the parietal lobe (dorsal stream) and temporal lobe (ventral stream) have reciprocal connections that enable the exchange of spatial and object information
• Feedback connections from higher-order areas to earlier visual areas (V1, V2) allow for top-down modulation of visual processing based on attention and expectations

Integration of information

• The dorsal and ventral streams ultimately converge in regions such as the prefrontal cortex and hippocampus, where spatial and object information is integrated
• This integration is necessary for the formation of coherent visual representations and memories
• In art, the integration of spatial and object information is crucial for creating and appreciating complex visual compositions

Dorsal stream and art

Perception of spatial relationships

• The dorsal stream's processing of spatial relationships is essential for the perception and creation of art that involves the arrangement of elements in space
• Artists rely on their dorsal stream to perceive and manipulate the spatial relationships between lines, shapes, and forms in their work
• Viewers of art also use their dorsal stream to perceive the spatial composition and layout of artworks

Depth and distance processing

• The dorsal stream's processing of depth and distance is crucial for creating and appreciating art that conveys a sense of three-dimensionality and space
• Artists use techniques such as linear perspective, overlapping, and shading to create the illusion of depth in their work, which relies on dorsal stream processing
• Viewers of art use their dorsal stream to perceive the depth and distance relationships within artworks, enabling them to experience the sense of space and immersion

Visuomotor coordination in art creation

• The dorsal stream's role in visuomotor coordination is essential for the physical creation of art, such as drawing, painting, and sculpting
• Artists rely on their dorsal stream to coordinate their visual perception with their motor actions, enabling them to accurately control their movements and create precise marks and forms
• The development of visuomotor skills through artistic practice may lead to enhanced dorsal stream function and spatial processing abilities

Ventral stream and art

Artistic style and content recognition

• The ventral stream's role in object recognition is crucial for the perception and appreciation of artistic style and content
• Viewers of art use their ventral stream to recognize and categorize the objects, scenes, and symbols depicted in artworks, enabling them to understand the subject matter and meaning
• The ventral stream also enables the recognition of artistic style, such as the distinctive brushwork or color palette of a particular artist or movement

Aesthetic appreciation and evaluation

• The ventral stream's processing of color, form, and texture is involved in the aesthetic appreciation and evaluation of art
• Viewers of art use their ventral stream to perceive the visual qualities of artworks, such as the harmony of colors, the balance of shapes, and the richness of textures
• The ventral stream's response to these visual qualities may contribute to the subjective experience of beauty and the formation of aesthetic preferences

Facial recognition in portraiture

• The ventral stream's specialization for facial recognition is particularly relevant for the creation and appreciation of portraiture in art
• Portrait artists rely on their ventral stream to accurately perceive and represent the unique features and expressions of their subjects' faces
• Viewers of portraits use their ventral stream to recognize and interpret the identity, emotions, and character of the depicted individuals

Disorders affecting streams

Dorsal stream disorders and art

• Disorders that affect the dorsal stream, such as visual agnosia or optic ataxia, can impair spatial processing and visuomotor coordination, which may impact artistic abilities
• Artists with dorsal stream disorders may struggle with perceiving and representing spatial relationships, depth, and motion in their work
• Viewers with dorsal stream disorders may have difficulty perceiving the spatial composition and layout of artworks, which may affect their understanding and appreciation

Ventral stream disorders and art

• Disorders that affect the ventral stream, such as prosopagnosia or color agnosia, can impair object recognition and color perception, which may impact artistic abilities and experiences
• Artists with ventral stream disorders may struggle with recognizing and representing objects, faces, and colors in their work
• Viewers with ventral stream disorders may have difficulty recognizing and interpreting the content and style of artworks, which may affect their understanding and appreciation

Research on streams in artists

Neuroimaging studies of visual pathways

• Neuroimaging techniques, such as fMRI and PET, have been used to study the visual pathways in the brains of artists and non-artists
• These studies have investigated the activation and connectivity of the dorsal and ventral streams during various artistic tasks, such as drawing, painting, and viewing art
• Some studies have found differences in the activation and connectivity of visual areas between artists and non-artists, suggesting that artistic training and expertise may be associated with changes in visual processing

Comparisons of artists vs non-artists

• Studies comparing artists and non-artists have investigated whether there are differences in the structure and function of the dorsal and ventral streams between these groups
• Some studies have found that artists show enhanced activation and connectivity in visual areas compared to non-artists, particularly in the ventral stream
• Other studies have found that artists may have greater gray matter volume or cortical thickness in visual areas, suggesting that artistic training and practice may lead to structural changes in the brain

Implications for art education

Training spatial skills via dorsal stream

• Art education that emphasizes spatial skills, such as perspective drawing, 3D modeling, and sculpture, may help to train and enhance dorsal stream function
• Engaging in activities that require the perception and manipulation of spatial relationships, depth, and motion may lead to improvements in dorsal stream processing and visuomotor coordination
• Incorporating spatial training into art education may not only improve artistic skills but also have benefits for other domains that rely on spatial abilities, such as mathematics and engineering

Enhancing object recognition via ventral stream

• Art education that emphasizes object recognition, such as still life drawing, portrait painting, and visual analysis, may help to train and enhance ventral stream function
• Engaging in activities that require the perception and representation of objects, faces, and colors may lead to improvements in ventral stream processing and object recognition abilities
• Incorporating object recognition training into art education may not only improve artistic skills but also have benefits for other domains that rely on visual perception, such as scientific observation and medical diagnosis