Question

Spike-timing dependent plasticity without acetylcholine and norepinephrine, as seen in NREM sleep, involves:

a) Increased plasticity
b) Decreased plasticity
c) No change in plasticity
d) Unpredictable plasticity fluctuations

Answer 1

Spike-timing dependent plasticity during NREM sleep without acetylcholine and norepinephrine typically results in decreased synaptic strength, hence the correct answer to the student's question is 'b) Decreased plasticity'.

Step-by-step explanation:

The student's question concerns the phenomenon of spike-timing dependent plasticity (STDP) in the absence of neurotransmitters acetylcholine and norepinephrine during NREM sleep. This form of plasticity relates to changes in the strength of synaptic connections in response to the timing of neuronal firing. Research indicates that during NREM sleep, when acetylcholine and norepinephrine levels are low, the brain engages in synaptic plasticity processes such as long-term potentiation (LTP) and long-term depression (LTD).

LTP generally leads to an increase in synaptic strength, while LTD leads to a decrease in synaptic strength. These processes are essential for learning, memory consolidation, and the overall health of neuronal circuits. Given the context of the question and the association between LTD and a decrease in synaptic strength, the correct answer is b) Decreased plasticity.