Download Chemistry of Psychology - Point Loma High School

Chemistry of Psychology
 Different sets of neurons= use different neurotransmitters
Neurotransmitters systems
 A group of neurons that communicate using the same Neurotransmitter
 Play roles in Emotion- Memory and Alzheimer’s
1921 – Otto Loewi
 First Identified Neurotransmitters using frogs
Neuro-modulators
Chemical like neurotransmitters
Modify the action of cell’s response to  Neurotransmitter
(P96) 3 classes of Neurotransmitters
1. small molecules
2. peptides
3. gases
Small Molecules
 Found in both Central and Peripheral Nervous system
Acetylcholine
 used by neurons Parasympathetic Nervous System
 to slow heartbeat
 to activate digestion by neurons that make muscles contract
In Brain
 Motor neurons, for movement
 Limbic system
o Hippocampus = memory
 Alzheimer’s – problems with Cholinergic neurons
Other Small Molecules- Neurotransmitters (Catecholamines= fight or flight arousal)
 Nor-epinephrine
 Serotonin
 Dopamine
(P96) Nor-epinephrine or Noradrenaline (related to Adrenaline and
Epinephrine)
 Both central and peripheral nervous system
 Contributes to Arousal
 Used by Sympathetic Nervous System to activate you-prepare you
for action
Reticular Formation (has lots of Norepinephrine)
 Wake and sleep
 Learning
 Regulation of mood
(P97) Serotonin = similar to epinephrine
 Occur in Hindbrain
 Hypothalamus
 Hippocampus
 Cerebral cortex
 Affects sleep + mood, depression
 Feelings of well being
 Aggression
 Impulse Control
 Suicide victims = low levels of Serotonin
 Created from tryptophan (found in food)
o Carbohydrates tryptophan serotonin
Dopamine
 Important for movement
 Problem of movement = Parkinson’s
o Pesticide exposure correlates with some Parkinson’s disease
o 70% incidence
o Treated with dopamine therapy
 Associated with Schizophrenia Also
 Affects pleasure + Reward Center of Brain
o Animals respond well to Dopamine
o They work to get Dopamine injections in experiments
o Drug addiction associated – cocaine
GABA (inhibiting)
 Amino Acid
 Neurons use GABA
 Inhibitory Neurotransmitter
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Drugs reduce neural activity also amplify inhibiting/Braking power of GABA
o Example Alcohol- impairment of thinking, judgment, motor skills
Malfunction of GABA = Severe Anxiety (too little GABA)
Huntington’s Disease
o Jerky movements
o Uncontrollable movement of arms and legs
o Dementia
o Loss of GABA containing Neurons
 Inhibited dopamine
 So when GABA neuron’s are damaged causes
 Too much Dopamine impairs motor neurons
 Impairs cognitive functions
Malfunction of GABA
o Related to Epilepsy
o Less GABA  intense repetitive electrical discharges
Glutamate (Excitatory)
 Excitatory Neurotransmitter (CNS)
 Used by more neurons than any other
 Lots in Cerebral Cortex and Hippocampus
 Too much Glutamate = causes neurons to die
 Plays a role in allowing and supporting synaptic connections allows messages
to cross synapse efficiently
 Important for learning & memory
(p98) Peptides= Endorphins
 Hundreds of chemicals act as Neurotransmitters
 Discovered in 1970s while investigating opiates
 Opiates –
o relieve pain
o Produce feelings of elation
o Bring sleep
o Bind with receptors
o Opiates were not known to be associated with neurotransmitters
o Researchers found the body already had substances similar to opiates
 Endogenous = “Naturally Occurring Morphine”
 Endorphin
o Any neurotransmitter that can bind to the same
receptors stimulated by opiates
o Especially- neural pathways that modify pain
signals