Anatomical Basis of Neurological Pathways Flashcards
what are the brain’s major cholinergic neurons?
- nucleus basalis of meynert (NMB)
- pedunculo-pontine tegmental nucleus (PPPT/LDT)
nucleus basalis of meynert (NBM)
- releases what NT?
- clinical significance?
releases ACh
- responsible for: conscious perception & cognition
- dysfunction leads to: Altzheimers
pedunculo-pontine tegmental nucleus (PPD/LDT)
- releases what NT?
- clinical significance?
releases ACh
- responsible for: dreaming & muscle atonia in REM sleep
- dysfunction leads to: REM sleep disorders - acting out dreams erractically, violently
what are the brains major histaminergic projections?
tuberulomamillary nucleus (TMN) in the hypothalamus
tuberomamillary nucleus (TMN)
- releases what NT?
- clinical significance?
releases histamine (& projects to cholinergic nuclei)
- responsible for:
- sleep modulation - arousal
- metabolism - inc metabolism
- dysfunction:
- hypoactivation:
- sleepiness
- high appetite -> obesity
- hyperactiviation:
- inability to sleep
- hypoactivation:
hypoactivation of the tuberomamillary nucleus leads to?
- increased sleep
- increased appetite, possibly obesity
hyperacitivation of the tuberomamillary nucleus (TMN) leads to?
inability to sleep (too aroused)
what are the major dopraminergic projections of the brain?
- ventral tegmental area (VTA)
- substantia nigra
ventral tegmental area (VTA)
- releases what NTs?
- clinical significance?
releases dopamine
- various responsibilities through different projections.
- mesocortical: executive function
- mesolimbic: reward
- tubuloinfundibular: regulation of PRL secretion
- dsyfunction of each :
- mesocortial: hypofunction -> negative sx of schizophrenia
- mesolimbic: hyperfunction -> positive sx of schizophrenia
- tuberuloinfundibular: hyperprolactinemia
the substantia nigra
- releases which NT?
- clinical significance?
releases dopamine
- via the mesostriatal projection:
- responsible for: coordinating movement
- dysfunction leads to: parkinsons
list the dysfunction causing each presentation
- Negative symptoms of Schizophrenia
- Positive symptoms of Schizophrenia
- Parkinson’s Disease
- Hyperprolactinemia
- hypofunctioning mescortical projection of VTA
- hyperfunctioning mesolimbic projection of VTA
- hypofunctioning mesostrial projection of STN
- dysfunctioning tuboinfundibular projection of VTA
what are the major noreadrenergic projections of the brain?
locus coeruleus (“blue spot”)
locus coerulus
- releases what NTs?
- clinical significance?
release a1, a2, and B2
- responsibilities:
- cortex & thalamus: attention / focus
- limbic system: feat / anxiety
- hypothalamus: sleepiness - inhibits inhibitors of VLPO
- defects:
- cortex & thalamus: hypoarousal -> ADHD, hyperarousal -> anxiety
- limbic system: hyperaousal -> mania, stress, PSTD
- hypothalamus: hyperarousal -> sleeeplessness
damage of the locus coeruleus neurons that project to the cortex & thalamus will lead to?
why?
- ADHD - with hypoarousal
- anxiety - with hyperarousal
this projection is responsible for attention & focus
damage of the locus coeruleus neurons that project to the limbic system will lead to?
why?
mania, stress, and PTSD (with hyperarousal)
this projection is responsible for fear & anxiety
damage of the locus coeruleus neurons that project to the hypothalamus will lead to?
why?
hyper = sleepless, hypo = sleepy
these projects release a2 (inhibitory) onto VLPO, inhibiting sleep induction
what are the serotonergic neurons of the brain?
the raphe nucleus - rostral, dorsal, median
the raphe nuclei
- releases what NT
- clinical significance?
releases serotonin (5-HT)
- responsible for: mood, sleep, anxiety
- dysfunction: hypoactivation of each projection
- to amygdala: sadness*
- to hypothalamus: appetite changes - too high or too low
- pituitary: menstrual, sleep disturbances
damage to which nuclei can can cause appetite disturbances?
- tubulomamillary nucleus (histaminergic) - hypoactivation -> overeating
- raphe nuclei (serotogenic) projecting to hypothalamus -> overeating or anorexia
clinical significance of orexinergic neurons
- role: maintaining proper vigilance
- dysfunction leads to:
- primary hypersomnia
- narcolepsy
- cataplexy - sudden loss in muscle tone
clinical significance of VLPO receptors
- induce sleep via GABA release
- lesions / damage lead to insomnia
dysfunction of what key nuclei can lead to sleep disturbance?
- REM sleep dsfyunction (acting out dreams): PPT (cholinergic)
- sleepiness: hypoactivation of tubulomamillary (histaminergic), locus coerulus (adrenergic)
- sleeplessneess: hyperactivation of tubulomamillary (histaminergic), locus coerulus (adrenergic)
- narcolepsy / cataplexy: orexinergic
which three neurotransmitters are ALL
- increased in excitement
- decreased in depression
- NE
- dopamine
- 5-HT (serotonin)
how do caffeine & alcohol afect GABA and glutamate?
- Caffeine: suppresses GABA, but stimulates glutamate
- Alcohol: stimulates GABA, but suppresses glutamate.
alchohol increases / decreases release of which NTs?
to have which effects?
activation
- GABA - sedation
- NE - stimulation
- DA - addiction / pleasure
inhibition
- Glu- slurred speech & memory disruption
nicotine increases ./ decreases release of which NTs?
to have which effects?
all activation
- cholinergic - energizes
- dopraminergic - addiction
- glutamergic - desire to use nicotine
dysfunction of which neurons can lead to mania?
loculus colerulus (adrenergic)
limbic projection
hyperactivation
dysfunction of what neurons can lead to ADHD?
locus colerulus (adrenergic)
cortical / thalamic projections
hypoactivation
