Final answer:
Prolonged deprivation of REM sleep due to antidepressant use can lead to increased anxiety as REM sleep is crucial for emotional processing and regulation.
Step-by-step explanation:
Prolonged, selective deprivation of REM sleep as a consequence of treatment with antidepressants can lead to several outcomes; however, considering the options provided, increased anxiety is likely. REM sleep is crucial for emotional processing and regulation. When denied this vital stage of sleep, individuals might not only miss out on benefits such as enhanced memory and cognition, which are associated with REM sleep but may actually suffer from heightened levels of anxiety. This is because REM sleep helps in managing the emotional response to stressful events, and without it, one may experience an increase in stress and anxiety. Antidepressants, especially selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs), can suppress REM sleep, potentially leading to these adverse effects.