PSYCH 120A Lecture Notes - Lecture 2: Lateral Geniculate Nucleus, Two-Streams Hypothesis, Parietal Lobe
Document Summary
Mri and pet scans cannot measure neural activity directly. Measures blood flow which is correlated with neural activity. Visual input low level vision high level vision knowledge. Low level vision: oriented bars and edges, motion, texture, depth. High level vision: object, face, scene, word recognition. Light comes in through the eye to hit the retina. Retinal cells sends input to back of the brain. Retina optic nerve lateral geniculate nucleus (lgn) primary visual cortex (v1) Single-unit recording: measure activity of a single neuron with electrode probe. Neuron"s do not receive signals from all spaces in the visual field. Neurons have some baseline so there will be some sort of signal regardless of location of stimulus. Can also map out orientations that are preferred. Convergence : as signal travels to further regions of the brain, neurons have a greater receptive field and respond selectively to specific shapes/stimuli. V1 v2 v4 it.
