Neurotransmitters and psychoactive drugs

ap psych

Excitatory Neurotransmitters

Excitatory Neurotransmitters

chemicals released by neurons that increase the likelihood of an action potential occurring in the postsynaptic neuron.

Glutamate

primary excitatory NT in the CNS. It is involved in learning, memory, and neural plasticity.

Inhibitory Neurotransmitters

chemicals released by neurons that decrease the likelihood of an action potential occurring in the postsynaptic neuron.

GABA

primary inhibitory NT in the CNS. It promotes relaxation/ reduces anxiety.

• undersupply= seizures, tremors, insomnia

Dopamine

plays a crucial role in regulating mood, reward, motivation, and movement. Brain’s reward system! “Feel good NT”

• Undersupply = tremors and limited mobility in Parkinson’s

Serotonin

NT that plays a vital role in regulating mood, sleep, appetite, and stress. influences mood and emotional well-being, essential NT for mental health. “Happy NT”

• Undersupply → depression

Endorphins

NT produced by the brain and central nervous system that act as natural pain relievers and mood enhancers.

• Released in response to stress, pain, or intense physical activity.

• Undersupply = depressed mood

Substance p

NT involved in transmitting pain signals in the nervous system.

• oversupply= chronic pain

Acetylcholine

NT that plays a role in both the CNS and the PNS.

• It is involved in muscle contraction, memory, and learning.

• In Alzheimer’s, AcH producing neurons deteriorate 
  

Norepinephrine

NT that helps control alertness and arousal

• undersupply leads to a depressed mood.

Psychoactive drug

 A chemical substance that alters conscious awareness, perception, and mood. 

Agonist

Drugs that increase the effect of an NT (making sure it will fire) —Ex: Opiates like Morphine & Heroin, are considered agonists of endorphins 

Antagonist

Drugs that decrease/ block the effect of a NT. 

• Ex: Botox (botulinum toxin) acts as an antagonist for AcH causing paralysis of muscles  

Tolerance

The diminishing effect with regular use of the same dose of a drug. 

Withdrawal

The discomfort and distress associated with discontinued use of a drug.  

• Nausea, aches, distress

Depressants

Reduce neural activity, slow down body function, inhibit the CNS

• Alcohol 

• Barbiturates / Benzos-tranquilizers (sleeping pills)

• Opiates 

  • EX: Morphine, heroin (allows dopamine to flood your neurons), fentanyl

Stimulants

 Excite neural activity and speed up bodily functions

• Caffeine

• Nicotine

• Cocaine...prevents reabsorption of Dopamine

• Methamphetamine…dopamine

• Ecstasy…mimics serotonin 

Hallucinogens

psychedelic drugs that distort perceptions and evoke sensory images in the absence of sensory input.  

• Marijuana 

• LSD