Summary
Hierarchical neurons detect edges, motion and objects, as shown by Hubel and Wiesel.
In depth
Retina to LGN to V1; V1 has simple and complex cells tuned to orientation; dorsal 'where' stream for motion and location, ventral 'what' stream for object identity. Hubel and Wiesel won the 1981 Nobel Prize.
Receptive fields grow more complex along the pathway. Visual information is processed in parallel streams. Damage to specific regions produces specific deficits.
Key idea: vision is constructed by the brain, not a camera.
Retinal ganglion cells have centre-surround receptive fields, and the LGN of the thalamus relays to V1 (striate cortex). Hubel and Wiesel found simple cells (oriented bars), complex cells (motion), and orientation columns and ocular dominance columns. Processing builds hierarchically from edges to shapes (V2, V4) to objects (inferotemporal cortex, with face-selective patches); the ventral 'what' stream and dorsal 'where/how' stream (Ungerleider and Mishkin; Goodale and Milner). Area MT/V5 handles motion, and V4 colour.
Lesions cause specific deficits: prosopagnosia (face blindness), akinetopsia (motion blindness), and blindsight (response to stimuli in a blind field without awareness). Deep convolutional neural networks resemble ventral stream hierarchy and were inspired by it. Visual illusions reveal processing assumptions.
Example: the brain fills in the blind spot, so you do not notice the gap.
Frequently asked questions
What is Visual Cortex Processing?
Hierarchical neurons detect edges, motion and objects, as shown by Hubel and Wiesel.
Which area of biology covers Visual Cortex Processing, and how advanced is it?
Visual Cortex Processing is one of the 54 topics in Neuroscience. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Neural Development, Language Areas of the Brain, Brain Regions.
Can you give an example of Visual Cortex Processing?
Damage to the fusiform face area causes prosopagnosia.
What should I learn before Visual Cortex Processing?
Work through the Beginner topics in Neuroscience first, such as Nervous System, Neuron, Central and Peripheral Nervous Systems, then return to Visual Cortex Processing. Advanced topics assume the Intermediate vocabulary.
What topics are related to Visual Cortex Processing?
The closest topics to Visual Cortex Processing are Neural Development, Language Areas of the Brain, Brain Regions, Sensory Receptors. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Visual Cortex Processing?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Visual Cortex Processing. To practise the whole of Neuroscience, use the Neuroscience quiz.
How is Visual Cortex Processing different from Neural Development?
Visual Cortex Processing: Hierarchical neurons detect edges, motion and objects, as shown by Hubel and Wiesel. Neural Development: Neurons are generated, migrate, extend axons and form synapses guided by chemical cues. Read both side by side and note what each one explains.
How should I study Visual Cortex Processing step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Neural Development and explain the difference aloud. Finally, take the Neuroscience quiz and come back to this page for any question you miss.