1. OPTION E E4 NEUROTRANSMITTERS AND SYNAPSES

2. E.4.1 STATE THAT SOME PRESYNAPTIC NEURONS EXCITE POST SYNAPTIC TRANSMISSION WHILE OTHERS INHIBIT POST-SYNAPTIC TRANSMISSION.
Pre-synaptic neurons can either excite or inhibit post-synaptic transmissions. (AP = “______________”)
This depends on which __________________(NT) is used and which _______________ they bind to.

3. Excitatory: NT __________ an AP in the post-synaptic neuron
E.4.1 STATE THAT SOME PRESYNAPTIC NEURONS EXCITE POST SYNAPTIC TRANSMISSION WHILE OTHERS INHIBIT POST-SYNAPTIC TRANSMISSION.
Excitatory: NT __________ an AP in the post-synaptic neuron
NT binding to the receptors opens _________ gates, causing sodium to flow in, ______________ the neuron.
Na+ in, neuron _________________, depolarization occurs.
NT: e.g. glutamate, acetylcholine (Ach), norepinephrine (NE),
_____________

4. Inhibitory: NT __________ an AP in the post-synaptic neuron
E.4.1 STATE THAT SOME PRESYNAPTIC NEURONS EXCITE POST SYNAPTIC TRANSMISSION WHILE OTHERS INHIBIT POST-SYNAPTIC TRANSMISSION.
Inhibitory: NT __________ an AP in the post-synaptic neuron
NT binding to the receptors opens __________ gates, causing chloride to flow in, _________________ the neuron.
Cl- in, neuron _______________, more difficult to depolarize, impulse ____________.
NT: e.g. _______, dopamine

5. ____________ = -Aminobutyric acid
E.4.1 STATE THAT SOME PRESYNAPTIC NEURONS EXCITE POST SYNAPTIC TRANSMISSION WHILE OTHERS INHIBIT POST-SYNAPTIC TRANSMISSION.
____________ = -Aminobutyric acid
GABA is a NT that opens _______________________ on the post- synaptic membrane. Cl- rushes in, _____________________ the post-synaptic neuron and _____________ APs.
GABA is important in regulating nervous processes – a “_____________” or depressive effect (reducing activity).
It prevents neurons from __________,
and can be used as a drug to help
people with anxiety or stress-related
disorders.
________ mimics the effect of GABA,
further increasing hyperpolarization
and therefore greatly reducing
nerve activity.

6. Important points to remember:
E.4.2 Explain how decision-making in the CNS can result from the interaction between the activities of excitatory and inhibitory presynaptic neurons at synapses.
Important points to remember:
- ________ of many neurons feed into the _________ of the
post-synaptic neuron
- each axon contributes to the _____________________ of the
- effects of the each input
can be either ___________
or ____________
- effect is ____________
and is added up at the
_________________.

7. multiple _________ from one input
E.4.2 Explain how decision-making in the CNS can result from the interaction between the activities of excitatory and inhibitory presynaptic neurons at synapses.
If the summative effect of the inputs reaches _____________, an AP is propagated.
Spatial Summation:
multiple __________
Temporal Summation:
multiple _________ from one input

8. Excitatory drugs Inhibitory drugs
E.4.3 Explain how psychoactive drugs affect the brain and personality by either increasing or decreasing postsynaptic transmission.
Excitatory drugs
Inhibitory drugs
Block re-uptake pumps for NTs
- NT __________________
e.g. cocaine’s effect on
dopamine
Mimic inhibitory NTs
________________ of
post-synaptic neuron
_______ APs
e.g. alcohol mimics GABA
effects, reducing APs
Mimic excitatory NTs
__________________,
_______ APs
e.g. nicotine
Blocks excitatory NTs
___________ APs
e.g. opiates (heroin)
block pain pathway by
competitive inhibition
Block inhibitory NTs
- prevent _______________
e.g. caffeine competitively
inhibit adenosine

9. _______: stimulate alertness and memory, nausea and vomiting
E.4.4 List three examples of excitatory and three examples of inhibitory psychoactive drugs.
Excitatory
_______: stimulate alertness and memory, nausea and vomiting
_________________: increases heart rate, respiration, alertness
_________________: causes anxiety and psychosis.

10. ___________________: muscle relaxant, reduces anxiety.
E.4.4 List three examples of excitatory and three examples of inhibitory psychoactive drugs.
Inhibitory
___________________: muscle relaxant, reduces anxiety.
________: slows and prevents movement, impairs reasoning skills.
________: reduces heart rate, breathing rate, and blood pressure.

11. Excitatory drugs = Cocaine
E.4.5 Explain the effects of THC and cocaine in terms of their action at synapses in the brain.
Excitatory drugs = Cocaine
Normal:
Dopamine acts as an ___________________
Dopamine is ______________ at the pre-synaptic neuron pumps
With Cocaine:
____________________ on reuptake pump
Dopamine not re-uptaken; remains in __________________
_________ dopamine is released
_____________ post-synaptic transmission
Effect on mood/behavior
Enhanced feelings of ___________(dopamine is a “pleasure” NT)
___________ energy and alertness
Highly ___________
Associated with ____________ (body reduces its own dopamine)

12. Inhibitory drugs = THC (cannibis)
E.4.5 Explain the effects of THC and cocaine in terms of their action at synapses in the brain.
Inhibitory drugs = THC (cannibis)
Normal:
Two pathways to consider
1) pathway released _________, increasing feelings of ________
2) _______ has an ___________ effect on release of dopamine
With THC:
Inhibits _________________ by binding to __________________
GABA cannot _______________
__________ dopamine is released
___________ post-synaptic transmission
Effect on mood/behavior
Enhanced feelings of __________ (dopamine is a “pleasure” NT)
______________ (drunk feeling), hunger, memory impairment

13. E4.6 Discuss the causes of addiction, including genetic predisposition, social factors, and dopamine secretion.
Addiction
- a __________________________disorder with genetic, psychosocial and environmental characteristics.
- is characterized by changes in the brain resulting in a
______________________to use a drug.
- “___________________” in the brain play a key role in
reinforcing behavior that may lead to addiction.

14. E4.6 Discuss the causes of addiction, including genetic predisposition, social factors, and dopamine secretion.
Reward Pathway
- makes one feel good when he/she engages in behaviors
that are ______________________(e.g. eating, drinking)
____________ is the NT most prevalent
in the reward pathway.
- generate a feeling of ___________
- high levels of dopamine cause a
feeling of ___________
- user may seek to repeat by using
the drug again (____________)
- ____________ of the drug leads to
anxiety, depression and craving

15. E4.6 Discuss the causes of addiction, including genetic predisposition, social factors, and dopamine secretion.
Some people are ______________ more pre-disposed to becoming addicted than others.
May be the result of genetically determined deficiency of __________________________
The children of addicts are ______________ to become addicts themselves.

16. E4.6 Discuss the causes of addiction, including genetic predisposition, social factors, and dopamine secretion.
Psychosocial factors are a heavy influence in addiction: