what are the parts of the forebrain
cerebral hemispheres
diencephalon (thal, hypothal, pineal, pituitary)
what are the parts of the hindbrain
medulla, pons, cerebellum
axial/horizontal
coronal
saggital
parallel to floor
connects ear to ear
line dividing 2 hemispheres
roles of orbitofrontal/ventromedial frontal lobe
emotion regulation
reward monitoring
personality
damage results in:
disinhibition
disordered reward processing
think PHINEAS GAGE: orbitofrontal damage
role of dorsolateral regions of frontal lobe
cognitive/executive functions
damage results in:
dysexecutive syndromes
working memory impairment
poor attentional control
poor word list generation
sometimes abulia/amotivation
think ADHD
role of dorsomedial region of frontal lobe
intentional and behavioral activation
damage results in:
problems with behavior initiation
what are three regions of temporal lobes
temporal pole: polymodal convergence zone (intersensory integration, semantic memory)
ventral temporal: object recognition, discrimination (bilateral damage results in obj or face agnosia)
posterior temporal: (middle and superior sulci): primary auditory area, Wernicke’s area (and prosody comprehension in non-dom hem)
3 regions of parietal lobe
superior: sensory-motor integration, body schema, spatial processing
temporoparietal junction: phonological and sound-based processing, language/music comprehension
inferior: complex spatial attention, integration of tactile sensation, self-awareness (think NEGLECT)
what are the 2 main visual cortical pathways
ventral/what stream: connects occipital and temporal. Object and face recognition, item-based memory, complex visual discrimination
dorsal/where OR HOW stream: connects occipital and parietal. Spatial vision & visuomotor integration
anatomy of the occipital cortex
damage causes:
primary visual cortex and visual association areas
damage causes cortical blindness or things like Anton syndrome (blindness but anosagnosia) or blindsight (some ability to perceive some info despite blindness)
how many layers of cells (laminar structure) are present in cortex vs. limbic system
6 in cortex
3 in limbic system (lizard brain)
in order to have a dense amnesia, whta must happen
damage to the TWO memory circuits:
medial (papez, involving hippocampus) circuit AND lateral circuit (involving amygdala)
what is the basal forebrain
it’s located at the junction of the diencephalon and the cerebral hemispheres.
its role is important for memory - but most lesion cases include a large lesion that impacts other key anatomical regions involved in memory
what cog functions is the thalamus involved in
sensory relay!
alertness, behavioral activation, memory
what may be key for memory are the white matter pathways (Internal Medullary Lamina) that transmit information from mammilary bodies to the anterior and dorsomedial thalamus.
in what % of left handers is language localized to the LEFT hemisphere?
60-70%
what is Wernicke’s area responsible for and where is it located?
Wernicke’s area is responsible for identifying sounds as words. Posterior Brodmann areas 33
it’s located in the perisylvian region of the temporal lobe, just posterior to Heschl’s gyrus (primary auditory cortex)
Broca’s area
plans and activates sequences of speech sounds - then sends to regions like face area of primary motor cortex
responsible for language generation; damage produces NONFLUENT aphasia
arcuate fasciculus
connects Brocas and Wernicke’s area - must be intact in order to be able to repeat language
damage would result in “conduction aphasia”
prosody & brain regions
right hemisphere - aligns with language regiosn in Left.
damage in inferior right frontal lobe = deficit in expressing prosody (like Broca’s aphasia)
damage in right posterior temporal/parietal lobe = deficit in prosody comprehension (like Wernicke’s)
Wernicke’s area connects with supramarginal and angular gyri in parietal lobe - what is this system responsible for?
language comprehension
writing
lexical semantics (mapping sounds to meaning)
transcortical motor aphasia
difficulties with generating language - halting speech but CAN REPEAT (unlike in Broca’s)
damage in frontal
anomic aphasia
can understand
can speak
can repeat
BUT difficulties finding the right word
conduction aphasia
can understand
can speak
CANNOT repeat
damage to arcuate fasciculus
what is the difference between transcortical and core (Broca’s, Wernicke’s, Global) aphasias?
in transcortical, you CAN repeat
