Neuro 2.2 - telencephalon

telencephalon

______________ is the two large hemispheres separared by the longitudinal fissure

• neocortex - 6 layers

• paleocortex - 3-5 layers

• archicortex - max of 3 layers

what are the 3 major divisions of the cerebral cortex? order them from highest to lowest amount of layers (list the layers)

90

the neocortex covers about _____% of out cerebral cortex

paleocortex

the _____________ division of the cerebral cortex covers parts of the olfactory cortex: parahippocampal gyrus and uncus

archiocortex

the _______________ division of the cerebral cortex covers parts of the limbic cortex: hippocampal formation and dentate gyrus

pyramidal

_____________ cells are the primary efferent neuron of the cortex

Glutamate and aspartate; excitatory

what are the neurotransmitters of pyramidal cells? are they excitatory or inhibitory?

• spiny cells (spiny stellate)

• aspiny stellate cells (granule cells)

• basket cells

what are the types of cortical interneurons/local circuit neurons

GABA; inhibitory

what is the main neurotransmitter of cortical interneurons/local circuit neurons? is it excitatory or inhibitory?

• molecular

• external granular

• external pyramidal

• internal granular

• internal pyramidal

• multiform

lamellar organization of the neocortex/homotypical, most superficial to deep

few

does the molecular layer of the neocortex have a lot or a few cell bodies

molecular (I)

which layer in the neocortex is a meshwork of axons and dendrites

molecular (I)

which layer in the neocortex is closest to the pia

external granular and pyramidal (II and III)

which layer in the neocortex has calls that are predominately in cortical circuits (corticocortical projections)

internal granular (IV)

which layer in the neocortex is the primary receptive layer

spiny and aspiny

what kind of cells are in the external granular layer of the neocortex

internal granular (IV)

which layer in the neocortex do most thalamocortical fibers terminate

internal granular (IV)

which layer in the neocortex is the outer line of Baillarger

medium and large pyramidal cells

what kind of cells does the internal pyramidal layer in the neocortex have

internal pyramidal (V - because of its abundant pyramidal cells)

which layer in the neocortex is the principle efferent layer from the cerebral cortex

fewer

does the internal pyramidal layer have more or fewer axons going to the thalamus compared to the multiform layer

multiform (VI)

which layer in the neocortex is primarily corticothalamic projections

pyramidal

what kind of cells does the multiform layer in the neocortex have

• corticocortical (from one gyrus to another, commissural or association)

• thalamocortical (specific, going to layer IV - internal granular - primary receptive layer)

two types of afferent information going to cortex

multiform (VI)

efferent info from internal pyramidal (V) or multiform (VI):

going mostly to thalamus

multiform (VI - cortex to thalamus)

efferent info from internal pyramidal (V) or multiform (VI):

corticothalamic

internal pyramidal (V)

efferent info from internal pyramidal (V) or multiform (VI):

going mostly to brain stem, spinal cord, and basal nuclei

external granular and pyramidal (II and III)

which layers are sending efferent information to other cortical regions

homotypical (all 6 layers clearly definable and roughly equal)

homotypical or heterotypical

agranular heterotypical (motor - layer V well developed and IV is indistinct)

homotypical or heterotypical

granular heterotypical (sensory - layer IV is well developed and V is indistinct)

homotypical or heterotypical

granular

a ____________ heterotypical cortex has terminations of sensory specific thalamic nuclei

agranular

a ____________ heterotypical cortex typically deals with motor related functions

ventral anterior/ventral lateral

where do efferents from the cerebellum go to in the thalamus

post

glutamate is excitatory for post or pre synaptic cells

neurotransmitter

neurotransmitter or neuromodulator:

axon to dendrite

neuromodulator

neurotransmitter or neuromodulator:

more diffuse, longer lasting effect

thalamus and subcortex

what 2 areas is the cerebral cortex receiving afferent information from?

• excitability of cortical neurons

• general arousal state

• attention/readiness to attend to stimuli (focus on signal and not the noise)

• alter motivational state

• neural plasticity

what are the 5 general functions of the neuromodulatory system

neuropsychiatric disorders:

• Mood disorders – depression, mania

• Anxiety disorders

• Schizophrenia

• Attention disorders

• Alzheimer’s disease

• Cognitive aspects of Parkinson’s disease

list some examples of disorders caused by dysfunction/imbalance implicated in neuromodulatory systems

cholinergic (Ach)

______________ is an example of a neuromodulator that causes extra thalamic input to the cortex, a lack of this is implicated in alzheimers disease

• noradrenergic

• serotonergic

• dopaminergic

• histaminergic

what are the neuromodulatory systems

noradrenergic

the _____________ neuromodulatory system is where the locus ceruleus responds to changes in sensory input, ex. enhance signal to noise ratio

noradrenergic and serotonergic (5-HT)

serotonergic (5-HT)

which two neuromodulatory systems combined can produced depression, anxiety, aggressive behavior, eating disorders, obsessive compulsive disorder

of those two, which one can cause these conditions alone (not combined)

serotonergic (5-HT)

the _____________ neuromodulatory system is from the raphe nucleus of pons and midbrain, can enhance or suppress neuronal activity

dopaminergic

the _____________ neuromodulatory system is from the ventral tegmentum of midbrain and substantia nigra, pars compacta; dysfunction of this system is implicated in hallucinations of schizophrenia, cognitive dysfunction of parkinson’s disease, alzheimers disease

histaminergic

the _____________ neuromodulatory system is produced by the hypothalamus and plays a role in wakefulness and inhibition associated with sleep

frontal lobe and premotor cortex

what parts of the brain are affected by a prefrontal lesion

agnosia (lesion of sensory association cortex, ex. put hand in pocket and know if it’s keys or coins)

____________ is the inability to recognize or interpret familiar objects, people, sounds, smells, or tastes despite having intact sensory functions

• restraint (judgement, foresight, concentration, delay gratification)

• initiative (curiosity, motivation, drive, creativity, personality)

• order (abstract reasoning, working memory, planning, insight, organization)

3 functions of the prefrontal

prefrontal

the ____________ region of the brain is important for learning new material, selective attention, and integration of information in decision making

disconnection syndromes

_________________ is dysfunction caused by damage to association or commissural pathways; for example, a lesion to the corpus callosum

• association

• commissural

• projection

(ACP)

what are the three fiber pathways in the medullary center

short association fibers

the ____________________ cerebral fiber pathway connects neighboring gyri

arcuate fasiculus

the ____________________ cerebral fiber pathway connects frontal-parietal-temporal

cingulum

the ____________________ cerebral fiber pathway has connections withing the parahippocampal gyrus

uncinate fasiculus

the ____________________ cerebral fiber pathway connects temporal to frontal

superior longitudinal fasciculus

the ____________________ cerebral fiber pathway connects frontal-parietal-occipital

inferior fronto-occiptial (passes through temporal lobe)

the ____________________ cerebral fiber pathway connects frontal occipital

superior longitudinal fasciculus

which cerebral fiber pathway

uncinate fasciculus

which cerebral fiber pathway

anterior commissure

the ____________________ cerebral fiber pathway connects temporal to temporal

corona radiata

the _______________ projection fibers are between the cortex and internal capsule

internal capsule

the _______________ projection fibers project from the cortex to subcortical structures

• Cingulum

• Sup. Longitudinal fasciculus

• Uncinate fasciculus

• Inf. Fronto-occipital fasciculus

• Arcuate fasciculus

what are the 5 long association fiber pathways