explain: daniel wolpert’s hypothesis on why humans have brains
- reason for brain is for motor mvt
⤷ brains integrate sensory cues, memory, and cognitive elements into appropriate mvt. - believes all beha. comes back to mvt.
- ex. sea squirts
⤷ digests their brain and NS when they no longer need to move
explain: aristotle + his idea of mentalism
- was one of the first ppl to consider why ppl differ + what in the body makes them diff.
⤷ believed the mind was what differentiated ppl
⤷ mind governed body - mentalism = idea that there is a mind and it’s in the body
explain: aristotle’s cardiac hypo.
- hypo. the mind is in the heart
- thought the heart governed beha.
explain: galen’s brain hypo.
- hypo. the mind is in the brain
⤷ saw that everything led to the brain (ex. neural connections to organs + limbs)
explain: descarte’s idea of dualism + mind body problem
- 2 opposing processes happening in body
⤷ mind is non physical (like a soul)
⤷ mind resides in brain - causes mind body problem
⤷ bc how can a non physical thing govern a physical body
explain: phrenology
- mapping out the brain + what each part governs
⤷ used to map by feeling ppls heads - gave insight that diff. parts many be involved in diff. activities
explain: broca’s findings about language
- saw patients w/ lang. deficites assoc. w/ mvt.
- damage (broca’s aphasia) -> speak slowly + hard to form sentences
⤷ from damage to broca’s area (frontal cortex, L hemisphere)
⤷ shows impact on motor mvt.
question: where is broca’s area?
- frontal cortex/lobe
⤷ closer to front side of brain - L hemisphere
- above lateral fissure
explain: wernicke’s findings about language
- didn’t agree w/ strict localization idea from broca’s findings
- found that another area in brain could lead to lang. deficits
- damage (wernicke’s aphasia) -> speak words but disorganized sequentially
⤷ can also mean disorganized thoughts
define: strict localization
- only that part of the brain is involved in that function
⤷ ex. broca’s findings about mvt. of language was used as evi. that lang. resides entirely in one part of the brain
question: where is wernicke’s area?
- temporal cortex/lobe
⤷ closer to back side of brain - L hemisphere
- below lateral fissure
explain: wernicke’s model of sequential flow of info for language in brain
- auditory info travels to temporal lobes from ears
- sounds processed into auditory representations/images
- aud. images stored in wernicke’s area
- aud. images sent through arcuate fasciculus (arcs around lateral fissure)
- goes to broca’s area -> turn images into speech mvt. + stored
- speech mvts. sent to muscles that control mouth to prod. sounds
question: what would happen to speech if there is damage in temporal lobe?
- damage to wernicke’s area -> speech would not make any sense
- broca’s area is still intact -> can still have proper speech mvts.
question: what would happen to speech if there is damage in frontal lobe?
- damage to broca’s area -> loss of speech mvts.
- no loss of sound images but cannot produce proper sounds
- not usually accompanied w/ loss of understanding
⤷ wernicke’s area still intact so comprehension is still preserved
explain: brodmann’s contributions to brain mapping
- mapped cytoarchitecture of brain
- looked at brain at a microscopic lvl
⤷ density of cells, types of neurons, etc. - mapped 6 layers of the brain’s cortexes
⤷ determined that diff. layers had diff. charac. of cells - work was very influential
⤷ even till today (PET scans, fMRI)
question: what makes up NS? CNS? PNS?
NS = CNS and PNS
CNS = brain and spinal cord
PNS = somatic and autonomic NS
⤷ somatic -> motor control
⤷ autonomic -> parasympa, sympa, enteric NS
explain: penfield’s contributions to brain mapping
- developed the sensory homunculus
- main goal at that time was to try and treat epilepsy
⤷ abnormal neuron activity - surgeons suggested removing parts of the cortex they thought were the cause of the seizures
- penfield mastered technique of stim. brain to find part that caused seizures
⤷ as he stim. diff. parts, he saw that activating diff. parts led to func. in diff parts of body
⤷ used this to map what parts encoded what
explain: patient HM
- began experiencing seizures after being hit in the head
- at the time, surgeons removed part of the cortex that cause the seizures
⤷ HM had majority of his temporal cortex removed - lost the ability to create memories
⤷ procedure cut into the hippocampus
⤷ could only hold for about 20s bc held w/out the hippocampus
