Which class excites neural activity and speeds up body functions; examples include nicotine, cocaine, and caffeine?

Which class excites neural activity and speeds up body functions; examples include nicotine, cocaine, and caffeine?

• A. Depressants
• B. Hallucinogens
• C. Stimulants
• D. Opioids

Answer: (C)

Stimulants excite neural activity and speed up body functions. They raise alertness, energy, and often heart rate and blood pressure by enhancing activity in the brain’s arousal and reward systems. Nicotine, cocaine, and caffeine fit this category because each increases neural signaling in ways that heighten wakefulness and physiological responsiveness: nicotine stimulates acetylcholine receptors to boost dopamine and other neurotransmitters; cocaine blocks the reuptake of dopamine and norepinephrine, flooding reward and arousal pathways with signals; caffeine blocks adenosine receptors, reducing perceived fatigue and increasing neuronal firing. In contrast, depressants slow CNS activity, hallucinogens primarily alter perception and thought, and opioids depress neural activity and respiration.

Stimulants excite neural activity and speed up body functions. They raise alertness, energy, and often heart rate and blood pressure by enhancing activity in the brain’s arousal and reward systems. Nicotine, cocaine, and caffeine fit this category because each increases neural signaling in ways that heighten wakefulness and physiological responsiveness: nicotine stimulates acetylcholine receptors to boost dopamine and other neurotransmitters; cocaine blocks the reuptake of dopamine and norepinephrine, flooding reward and arousal pathways with signals; caffeine blocks adenosine receptors, reducing perceived fatigue and increasing neuronal firing. In contrast, depressants slow CNS activity, hallucinogens primarily alter perception and thought, and opioids depress neural activity and respiration.