brain and behav exam 2

general process approach

biological and psychological principles are the same/similar in many species

justifies using rats for neuroscience

vivisection

surgery performed on a live animal

lesions

injury/wound to the brain

microdialysis

surgery tool inserted into brain through cannula to measure fluids in the brain

microtone

device that creates thin brain slices (like a deli slicer)

neurohistology

the study of tissue and cells in the nervous system

neuron doctrine

ramon y cajal

neurons are not interconnected and not one big web

golgi staining method

staining method

turns neurons darker to allow you to see the neuron in detail

nissl staining

staining method

reveals nissl in brain and shows separation of neurons in packed areas

green fluorescent proteins

staining method

makes proteins of brain glow allowing distinction of cell bodies

brainbow

immunostaining

staining method

antibodies in the immune system

ECG/EKG

measures heartbeat and tracks heart muscle contractions

HRV

tells how person deals with stress

time difference between each successive heart beat

EDA/GSR/SCU

measures electric responses in skin from sweat on hands/palms

EMG

measures contractions of muscles under surface of skin

CT scan

like an xray

quicker/cheaper and used for emergencies

poor spatial resolution

MRI

interaction between radio frequency waves and strong magnetic field (hydrogen in blood)

big magnet

slightly dangerous/lot of concerns

better spatial resolution (shows white/grey matter)

DTI

measures direction and movement of water within brain

reveals bundles of myelinated axons (white matter) but not grey matter

EEG

looks at brain waves and measures electrical activity of population of neurons

“swim cap” with gel

used for sleep study/epilepsy

MEG

SQUIDS

measures magnetic energy

fMRI

measures oxygen in blood (BOLD)

“indirect” measure (5-10 sec delay)

PET

relies on hemodynamic/metabolic response

measures blood flow via oxygen and glucose metabolism

revels localization of radioactive tracer

TMS

electromagnetic coil produces magnetic field on head to produce changes in corticals to stimulate/inhibit brain areas

good for treatment resistant depression

Deep brain stimulation (DBS)

electrode implanted to brain brain area for stimulation

expensive and only used if meds arent working

helpful for parkinsons

DNA

where genetic info is stored (blueprints)

found in nucleus of every cell in body

genes

specific and small sections of DNA

make functional proteins

chromosomes

23 pairs (46 total)

1 set from each parent

genotype

complete set of genetic info (specific alleles found in chromosomes)

phenotype

how genes are expressed physically

(ex: eye color, hair color)

law of segregation

alleles segregate during development (1 allele from each parent)

phenylketonuria (PKU)

disorder impacts how amino acid (phenylamine) is broken down

leads to low dopamine levels in individual and effect different cognitive and behavioral processes

epigenetics

study of how environmental factors impact phenotypes of genes

studied using DNA sequencing and testing

optogenetics

stimulate/inhibit neurons in specific regions of brain

uses different wavelengths of light

heritability

specific statistic to estimate % of variation of trait through environment and genetics

studied using twin studies

monozygotic (MZ) twins

identical twins (single egg split in 2)

100% same DNA

dizygotic (DZ) twins

fraternal twins (2 different eggs in one womb)

50% same DNA (like regular siblings)

concordance rates

tells risks of developing disorders between people who are related

higher=higher heritability

natural selection

charles darwin

positive eugenics

people with “good” traits encouraged to reproduce

negative genetics

people with “bad” traits are discouraged from reproducing

led to forced sterilization of minorities

sensory transduction

converting physical properties (light and sound) to changes in the nervous system ex: the rate of action potentials

structures of eye

cornea

lens

retina

cornea

where light first enters the eye

protects eye and is where 70-80% of focusing occurs

lens

controls 20-30% of eyes focusing power

retina

cells in the back of the eye

where transduction takes place

rods

photoreceptors sensitive to low intensity light and movement

useful for night vision

cones

photoreceptors important for daily vision, high detail color processing

scotopic vision

processes movement and low intensity light

photopic vision

processes colors, shapes, and fine detail

myopia

near sightedness

can see upclose and not far

hyperopia

farsightedness

cant see things up close but can see far

cataracts

inner lens becomes cloudy and causes vision to be foggy

getting worse = blindness

can be treated with lens replacement but still need glasses

macular degeneration

macula deteriorates and impacts middle visual field

middle is fuzzy and could turn blind

no cure but treatment can slow

retinitis pigmentosa

genetic disorder where outer retina is affected causing blindness everywhere but in the middle (tunnel vision)

trichromatic theory

color vision theory

3 types of cones sensitive to different wavelengths of light

blue, green, and red cones

opponent process theory

ganglion cells colors paired up

yellow+blue and red+green

ON ganglion cells

cells fire more when light is in the middle

fire slower when light hits the side

OFF ganglion cells

cells fire slower with light in the middle

fire faster when light hits the side

primary visual pathway

retina → optic nerve → optic chiasm → thalamus (LGN) → v1 → v2-v8

optic chiasm

where left and right visual pathways cross

primary visual cortex (v1)

AKA striate cortex

responds to specific features (lines, edges, angles)

extrastriate cortex (v2-v8)

specialized to respond to certain visual features

adds form, color, etc (detail)

ventral stream

extrastriate pathway

allows you to understand what you are looking at

WHAT stream projects to inferior temporal cortex

dorsal stream

extrastriate pathway

helps with spatial navigation and skilled movement

WHERE stream projects to posterior parietal lobe

facial processing is better where

right hemisphere

prosopagnosia

not being able to recognize faces

can see other details (hair, clothes, etc) but not faces

olfaction

smell

does not pass through thalamus

gustation

taste

olfactory receptor neurons (ORNs)

inside the epithelium

odorants bind and carry into the olfactory bulb

olfactory bulb

where smell info enters the brain

smaller in humans than animals (ex: dogs)

mitral cells

in olfactory system

bundles axons together to form olfactory nerve to send info to brain

glomeruli cells

in olfactory bulb

dendrites meet with terminal buttons of olfactory receptors

specific cells respond to specific smells

papillae

the bumps you can see on the tongue

taste buds are INSIDE

primary gustatory cortex

processes taste

insula and frontoparietal operculum

the end of lateral fissure that facilitates taste perception