AP Psychology College Board

Influenc of Drugs on Neural Firing

Influence of Drugs on Neural Firing

Neurotransmitters and Drugs

• Neurotransmitters are the body's natural chemicals that transmit messages between neurons.
• These messages can be either inhibitory (reducing the likelihood of the neuron firing) or excitatory (increasing the likelihood of the neuron firing).
• Some drugs can mimic neurotransmitters, essentially fooling neurons into triggering a response.
• Others can block neurotransmitters, preventing the normal message from getting through.

Opium and Morphine

• Opium and its active ingredient, morphine, bind to specific neurotransmitter receptors in the brain, the opioid receptors.
• This decreases the sensation of pain and induces feelings of euphoria.

Psychoactive Drugs

• Psychoactive drugs, such as LSD and ecstasy, alter consciousness by modifying perceptions and moods.
• Some of these drugs, like LSD, bind to serotonin receptors, changing the person's sensory perceptions and thought processes.
• Other drugs, such as ecstasy, increase the release of serotonin while blocking its reabsorption, leading to an elevated mood.

Depressants and Stimulants

• Depressants, such as alcohol, reduce neural activity and slow body functions by increasing the production of GABA, an inhibitory neurotransmitter.
• Stimulants, such as caffeine and nicotine, excite the neurons and speed up body functions. Caffeine blocks adenosine receptors, reducing the feeling of tiredness.
• Nicotine stimulates the release of dopamine, creating a sense of pleasure and addiction.

Alcohol and GABA receptors

• Alcohol influences the GABA receptors in the brain, which are responsible for reducing excitability and promoting calm and relaxation.
• By increasing the effects of GABA, alcohol acts as a central nervous system depressant, slowing down thinking, breathing and heart rate.

To understand the influence of drugs on neural firing, it's important to recognise the role of neurotransmitters and how different types of drugs either mimic, block, or modify the action of these neurotransmitters. Such understanding provides a basis for comprehending the physiological and psychological effects of drugs on the human body and mind.