Vision
What does the lens do?
Focuses light in adjustable way
What the middle ear bones?
Malleus, incus and stapes
OR
Hammer, anvil and stirrup
Toward the top of the brain
Dorsal
Functions of cerebrospinal fluid
Describe the frequency theory
The basilar membrane vibrate in synchrony with sound which causes action potentials at the same frequency.
Different frequencies of sound lead to different frequencies of action potentials.
Compare rods and cones
Rods respond to fainter light and are more abundant in the periphery.
Cones respond to brighter light and are common in and near the fovea.
How do hair cells transform sound into an electrical signal
Vibrations in fluid cause the hair cells to bend. As they bend ion channels open (mechanically gated), K+ and Na+ enter the cell and trigger neurotransmitter release
A cluster of cell bodies within the CNS
Nucleus
Functions of the reticular formation
How did they discover cortical receptive fields?
Using anesthetized cats. Show cats a screen with light patterns and recorded from the cells in the cortex. Found little response to dots of light but big response to edges of the slides.
Describe Opponent Process Theory
There are 3 types of cones (L,M,S) that respond to different wavelengths. Long and medium cones excite the horizontal cell, then inhibit the bipolar cell. Short cones excite both the horizontal and bipolar cones.
What is a tonotopic map?
A map on the brain showing that tones near each other in frequency are near each other in the brain
What division of the brain is responsible for sleep, respiration, swallowing, facial expression/sensation
Hindbrain (pons)
Compare sympathetic to the parasympathetic nervous system
The sympathetic nervous system is the emergency response (fight or flight) while the parasympathetic nervous system is the non-emergency response (rest & digest)
Describe place theory
each place along the basilar membrane is tuned to a specific frequency
What produces sharp borders and excites photoreceptors?
Lateral inhibition
How is pitch encoded for middle frequency sounds?
The volley principle- the whole auditory nerve produces volleys of impulses
3 major divisions of the brain
Hindbrain (medulla, pons, cerebellum)
Midbrain (tectum, tegmentum, substantia nigra)
Forebrain (thalamus, hypothalamus, hippocampus, basal ganglia, cerebral cortex)
Describe the postcentral gyrus
Primary somatosensory cortex
Different parts respond to touch and movement information from different parts of the body
Bell-Magendie Law
Dorsal roots carry sensory information, ventral roots carry motor information
Compare the Ventral and Dorsal streams
Ventral: through temporal cortex, identifies objects (what)
Dorsal: through parietal cortex, helps motor system locate objects (where)
How is sound localized based on type of sound?
Sudden onset sounds- time of arrival
High frequency sounds- sound shadow
Low frequency- phase differences
Name the basal ganglia in the forebrain
Caudate nucleus, putamen, globus pallidus
What are the 4 lobes of the brain and their functions
Occipital- vision
Parietal- somatosensory perception (touch), guided action, spatial information, numerical information
Temporal- auditory information, some motivational/emotional behaviors, complex vision
Frontal- motor function, language, attention, planning
Describe the visual development experiment using cats.
Suture one eyelid of kitten shut for 4-6 weeks. Synapses in the cortex stop responding to input from the deprived eye.
After removing sutures there is a sensitive period and response will be weak, but this effect gets weaker and weaker over time.