PSY 401 Exam #1 Flashcards
basic neuronal anatomy
dendrites (come off the soma, receive signals) –> soma (contains nucleus) –> axon –> (covered by) mylein sheath –> (interrupted by) nodes of ranvier –> terminal buttons pic
of neurons in human brain; comparison
86 billion; not remarkable, similar to other primates of our size
physiological props of neurons: the action potential
resting state = -70mv
depolarization = getting closer to 0mv
threshold state = -50mv
Na+ channels open causing depolarization, mv goes up +++ –> AP / “spike”
physiological props of neurons: fuel/energy use
brain is 2% of body weight but uses up 20% of oxygenated blood from the <3
physiological props of neurons: active conduction
the purposeful regeneration of an AP @ each node of rancvier; propogation of an AP from the soma down the axon; if the summation of dendritic signals passes the threshold it’s ALL or NOTHING
myelin sheath and nodes of ranvier
where the axon is covered in myelin, Na+ or K+i ons CANNOT enter/exit and AP has potential to slow down; nodes of ranvier interrupt the MS exposing the axon and allowing Na+/K+ to exit, essentially “re-creating” the AP at every stop
basic neuronal anatomy: myelin sheath and nodes of ranvier
where the axon is covered in myelin, Na+ or K+i ons CANNOT enter/exit and AP has potential to slow down; nodes of ranvier interrupt the MS exposing the axon and allowing Na+/K+ to exit, essentially “re-creating” the AP at every stop
brain structure: thalamus
“switchboard” of the brain, conducts signals from (ex) sensory organs, cerebellum, amyg to up cortex; has bidirectional connections to every cortex area
physiological props of neurons: passive conduction
uninhibited flow of elec signals from dendrites to soma
brainstem
medulla + pons + midbrain
func: HOMEOSTASIS, HOUSES CRANIAL NERVES
thalamus
SWITHCBOARD, CORTICAL RELAY (BOTHWAYS)
hippocampus
spatial navigation and episodic memory [place cells] ; bigger in taxi drivers, pianists (includes memory of more abstract domains)
amygdala
personal relevance of stimuli; danger, emotions
basal ganglia
(front and temp lobe) bunch of nuclei that contribute to development of habits;
- get lots of input from cortex, has 2 “no” or “go” pathways
cerebellum
regulates muscle tone, posture, smooth movement, timing, coordination
gray matter vs white matter
gray matter = cell bodies, located in within the cortex (in the cortex)
white matter = myleinated axons
cerebral cortex: 5th lobe!
insula: not visible externally, located beneath the sylvian fissure (which separates temp lobe from frontal and parietal)
gyri vs sulci
gyri: bulGes of cortical tissue
sulci: GROOVES within cortical tissue
https: //www.purposegames.com/game/brain-sucli-and-gyri-quiz
gyri & sulci: properties & benefits
- BOTH subject to individual human differences
- increased gyrification MAY have implications for increased cognitive abilities
- allow for a large surface area of tissue to be squeezed into the small cranial space; reduces the distance signals have to travel; reduces amount of axon wiring needed
cytoarchitectonic organization of the cortex
HORIZONTAL: ctx arranged in 6 layers of cells, arranged based on similarities in form and connection (where/what they innervate)
VERTICAL: ctx permeated by columns; cells in which respond to similar fts of the external and internal environment
broadmann areas
(43) imperfect; better as a STRUCTURAL organization / sectioning of brain areas than a functional one; BASED on CYTOARCHITECTONIC org of cortex
corpus callosum
tract of white matter connecting L and R hemispheres
fasiculi
tract of white matter connecting different cortical areas within the same hemisphere
diffusion tractography
type of fmri that tracks water molecules along axon fibers in white matter, allowing the visualization of fiber connections p19
syndrome
a group of symptoms that statistically co-occur within patients ex.
neuropsychology
utilizing instances of patient brain damage to reveal insights about it’s function - structure relationships
aims of neuropsychology in language study (2)
- understanding the cognitive architecture of lang; determining which components can be independently disrupted (ex. nouns v verbs, comprehension v production)
- understanding the neural architecture of lang; which lesion sites are assoc w which lang deficits
(p2)
neuropsychology: types of brain damage (4)
- stroke
- traumatic brain injury (tbi) - closed v open
- neurodegen and infectious disease (i.e. primary progressive aphasia)
- tumors
neuropsychological methods: lesion overlap and subtraction analysis
- “overlap maps” created for 2 separate groups - ppl with lesion and ppl without it
- lesion overlap map for DEFICIT ppl - lesion overlap map for ppl WITHOUT deficit = image highlighting areas specifically assoc w deficit