The Brain Flashcards
materialism concept
brain produces mind/What is the point/relationship between patterns and our experiences
how brain works in 5- words (steve pinker)
“Brain cells fire in patterns”
Brain cells–neurons
Fire–electrical signals
Descartes
He argued for dualism–mind and brain totally separate
Mental events–in our mind–are the stuff of the soul but sometimes they link up
Physical events–in our brain
Today we believe in materialism not dualism
Physical events (neurons firing) directly cause mental experiences/events
First evidence that ppl thought about brain
Trepanation (holes created in skull) (c 3500 BCE)–drilled into their brain when they were alive and survived for a while after
We dont know why they did it
do mental events cause other mental events?
No! Physical events can cause more than one mental event, though.
Smell cookies physical event neurons fire → mental event “smells good in here”
Neurons fire as result of first neurons firing → “cookies!”
Pattern corresponds to a thought, causes another pattern
SSRI vs placebo
physical event changes way neurons fire
With placebo
We have neural pattern → medicine makes u feel better
Materialism wins over dualism (=”mind is what brain does”)
SSRI vs placebo
physical event changes way neurons fire
With placebo
We have neural pattern → medicine makes u feel better
Materialism wins over dualism (=”mind is what brain does”)
history of (discovery of) brain (pre renaissance
Brain wasnt important to Egyptians–they preserved internal organs but not brain (they thought heart)
Greeks didnt know whether mental life existed in heart or head
Camillo Golgi
realized how to stain cells/the staining would only stain some cells and made everything look less complex–first evidence of cells in brain
globalization vs localization of function-
-is brain equal all over or made of different parts that do different things? Sponge (globalized/damage to one part=function across the board damage) vs bicycle (localization/damage to one part damages ur ability to do one thing)
Brain is localized=why more minor strokes affects some and not abilities
Localized function so important bc:
Multiple brain regions imply multiple cognitive functions (e.g. memory)
Remembering words =/= numbers, faces; they come from diff parts of the brain
Overlapping brain regions imply overlapping cognitive functions (e.g. gerstmanns syndrome)
Gerstmanns syndrome
which causes an inability to add and subtract, tell left from right, and tell which finger is being touched–so there must be some overlap in which part of the brain is being used to solve that problem–very specific spot
All have to do with hands
Brain injury (agnosia)
Cant visually recognize but can thru touch (diff parts of brain)
Franz gall
discovered localization
He also thought parts of brain grow if u use them
Phrenology–where brain could grow bumps→ traits
Wrong about bumps and traits, right about localization
Turns out cells changing if u spend more time on something/one area of neurons can overtake others
Methods localization/studying brain:
Accidents
Manipulation (stimuating diff parts)
Non invasive technique
phineas gage
Nice mild-mannered guy and then got brain injury and personality totally changed
Tamping down gunpowder w big metal rod and it set ff early and rod went thru his skull
He got up and said i think i need to go to the dr
Perfect hole
He went on to live normalish life except he became aggressive emotional outbursts, swearing, emotional reactivity problems
Damage to one part of functioning and the rest stay normal
Evidence for brain localization
Lobotomy
(not done anymore) disconnect front spot from rest of brain/cure behavior problems
Take away personality
animal subjects
But if u dont want to wait for accidents to study localization people use animal subjects
But damaging animals brains might be unethical and also humans and animal brains are not the same
surgical mapping
Then penfield discovered surgical mapping (w electrical current)/manipulation and people whose brains were being manipulated would report results
noninvasive techniques
Recent noninvasive technique–Transcranial Magnetic Stimulation
EEG another way to measure w/o disrupting–electrodes
Functional neuroimaging–
PET (sugar) and fMRI (magnetic resonance imaging)
Brain organization–
Everything we do is a continuum from luxury to necessity
Heartbeat–necessity
Necessary functions in middle of brain and moves out
Organized from evolutionary old to new
Ones on outside deal w fancy human things
cortex
outer surface w unique human abilities
Frontal lobe–
reasoning lang exec control
Temporal lobe–
audio, language, object recognition
Parietal–
pay attn, locate objects in space, counting
occipital–
responsible for vision
Bilateral symmetry in brain/functions of l/r
–right side of brain controls sensory and motor of left body and vice versa
Left–linguistic analysis (grammar, vocab)
Right–paralinguistic (tone, rhythm)
corpus collosum
Two sides connected by corpus callosum
Allows two sides to interact
If damage occurs they cant interact and weird stuff happens
history of (discovery of)brain post renaissance
Renaissance–they knew mental life was in brain
People thought fluid in brain (produced by ventricles) was the important part
Really it just keeps our brain tissue floating
Tissue vs ventricles
People started understanding anatomical structure in 1600s
When ppl first discovered cells they thought brain didnt have any bc neurons look so different with the tendrils/branches
then Golgi
Old debate–globalization vs localization of function
somatosensory cortex
The part of brain having to do with feeling on body
cortical homunculus
how man would look if we were built the way somatosensory or motor cortex projects
Motor cortex–
maps our movement
Transcranial Magnetic Stimulation
Use magnets to interrupt functioning
EEG
another way to measure w/o disrupting–electrodes detect electrical brain activity
Functional neuroimaging–
PET (sugar) and fMRI (magnetic resonance imaging) measures blood flow
Things that need more energy use more blood flow
