Midterm 1 pt 2 Flashcards
When generally staring at the Hermann grid we don’t get the illusion of grey spots bc we are using our _____ which lacks rods
Fovea
Neurons with receptive fields similar to ganglion cells in the left and right middle of the brain with 6 layers that contain topographic organization with adjacent cells having adjacent receptive fields on the retina
Lateral Geniculate Nucleus Cells (LGN)
Cells located in V1 have rectangular shape and orientation preference but not from a particular position, will respond to both light and darkness (bc simple cells are layered)
Complex Cells
Cells located in the V1 contain oriented receptive fields for elongated light or dark edges/bars; Do not have spontaneous activity
Simple Cells
True or False: Adjacent stuff in the world is projected onto adjacent points on the retina encoded by adjacent cells in the LGN
True
Idea that different brain regions have different functions
Localization of Function
Frontal left lobe area of the brain that is important for production of language
Broca’s Area
Cells located in V1 with orientation preference and directional motion but with limited length
End Stopped Cells or Hypercomplex Cells
Although hypercomplex cells aren’t width specific what happens eventually as the bar lengthens beyond the cells receptive fields?
The cells response will weaken bc objects in our environment have limited length
Brain surgeon recognized with brain mapping by using exposed brain of alert epileptic patients with a probe to deliver stimulation and recorded different locations evoking different responses
Penfield
Part of the brain where LGN is located and relays to the visual cortex
Thalamus
Left Hemisphere has neurons that control the _____ side of the body while the right hemisphere has neurons and receptive fields for the ____ side of the body
right; left
Environment you’re looking at which is divided into left and right halves with the fovea distinguishing the center
Visual Field
What is projected onto or near the fovea is projected to the primary visual cortex (monkey study); the fovea has a lot of cortex dedicated to it
Cortical Magnification
The _____ visual field from both eyes projects to your left visual cortex
right
Topographic organization where adjacent points of the retina are projected onto points that are adjacent onto the visual cortex
Retinotopy
The _____ visual field from both eyes goes to your right visual cortex
left
If there is a stimulus in your right visual field which hemisphere of the brain does it go to?
BOTH - Eyes do NAWT cross over the visual field does
V1 is organized into a ____ like pattern made up of columns and hypercolumns
grid
Pathway in primary visual cortex concerned with “where” information such as location, action, navigating and grasping
Dorsal
Pathway in primary visual cortex concerned with “what” information important for object recognition
Ventral
True or False: Each hypercolum has neurons with receptive fields corresponding to one region of the retina
True
Each hypercolumn contains an ______ _______ ____which are further organized as having receptive fields in either the left or right eye
Ocular Dominance Slab
The process of building a complex waveform (or maybe an image) by adding together simpler sine and cosine waves
Fourier Synthesis
Realistic receptive fields have extra _________ and _________ lobes that look like gabor functions which act as small patches of sine waves
Excitatory; Inhibitory
Building off hubel and wiesel the actual simple cell receptive field measures ______ _______ rather than just bars
Sine waves
True or False: Any pattern (image) can be created by summing small patches of sine waves (wavelets) of many different orientations and sizes
True
The alteration between light and dark regions over a given region of space (grating patterns)
Spatial Frequency
Graph that indicates a cells preference in spatial frequency
Tuning Curve
True or False: Different cells have different tuning curves for spatial frequency
True
How much a cell responds to contrast as the difference between light and dark in grating patterns also defines an envelope level of spatial frequency tuning in all V1 cells
Contrast Sensitivity Function
Contrast sensitivity function defines the ____ of what we can see
limit
Younger individuals have a _______ contrast sensitivity function in comparison to older individuals
Higher
During daytime (photopic) contrast sensitivity function is ____ while at night (scotopic) its _____
High; Low
