Biological bases and memory 2 Flashcards
synapses
how neurons communicates with each other across special junctions
neurotransmitter
when action potential arrives at an axon terminal-a special chemical is released at SYNAPTIC CLEFT
graded potential
receptor at the postsynaptic neuron respond to the neurotransmitter
neurotransmitter
- synthesized and then stored in VESICLES
- released
- binding
- reuptake
neurotransmission at synapses
drugs can have an effect by ALTERING
Agonist - triggers response
mimics the action of naturally occurring substance
indirect agonist
enhances the release / action of an endogenous neurotransmitter
antagonist
block/supress agonist-mediated responses
different neurotransmitter
- dopamine
- acetylcholine
- noradrenaline
- glutamate
- serotonin
the effects of changes in neurotransmission I
- Parkinson’s disease
- affects 1% of the population
- tremor
- muscular rigidity
- involuntary shifts of posture
- slowness of movement
- shuffling, wide-spread gait with forward leaning posture
the effects of changes in neurotransmission ii
-Schizophrenia
-affects 1% of the population POSTIVE symptoms: -delusions -hallucinations -disorganised thinking
NEGATIVE symptoms:
- blunted effect
- poverty of speech + thought
- apathy
COGNITIVE symptoms:
- poor working memory
- disruption in executive function/attention
Parkinson disease and Schizophrenia
- dopamine ANTAGONIST= antischizoprenic effects
- these produced Parkinson disease
- PD=degeneration of the Substantianigra (midbrain nucleus)
- PD treatment =dopamine ANGONIST (L-Dopa + Bromocriptine)
- Dopamine ANGONIST= triggers schizophrenia episodes in NORMAL individuals
dopamine
involved in Parkinson and schizophrenia and action of drug abuse
intracranial self-stimulation (ICSS)
- produce pleasurable effects in animals/humans
- activates dopaminergic pathways (Nucleus accumbens and VTA)