Transcript Columns and Hypercolumns

Erin Berrisford, Lisa Fenske, Adam
Justin, Sara Duxbury, Joe Tuzinski, &
Ryan Mastellar
History
 Hubel and Wiesel
 Used a recording electrode to push farther and farther down into the cortex, finding
neurons with similar response properties
 Neurons with similar orientation are arranged in vertical columns throughout the
cortex
What is a column?
A column is a trio of vertical cells
Respond to similar stimuli and characteristics
The cells in each column work together to interpret a
stimuli
Take a thick, yellow, slanted line
One cell interprets the yellow, another the thickness,
another orientation- all these cells work together to
see a yellow line that is thick and slanted
Each column prefers input from the left or right eye
Located in the striate cortex
Each column covers about .5mm
Hypercolumns
Contains at least two sets of columns that function as a
unit
Each is like a mini computer
Each perceives one small portion of the visual field
Enough columns to cover every possible orientation (0180 degrees)
Each hypercolumn is about 1mm across
 Half of the hypercolumn responds to light falling on the
left retina, the other half responds to light falling on the
right retina
 Each hypercolumn has enough cells to respond to light,
orientation, and bar width
 Includes a pair of columns called blobs
Blobs
Function unclear
CO blob columns are thought to aid in processing color
(CO stands for cytochrom oxidase- a staining technique
enzyme)
Interblob regions process motion and spatial structure
Demonstration
http://www.sinauer.com/wolfe2e/chap3/hypercolumnsF.htm
Scan in picture and place here
To Sum up
 Hypercolumns are used by the striate
cortex to analyze size, shape, speed, and
direction
Each cell is in charge of a certain
characteristic but all work together to
create the pictures we interpret from the
visual world