What is the MOST LIKELY cause of a 35-minute REM latency?

A 35-minute REM latency is indicative of the time it takes for a person to enter REM sleep after falling asleep. In a healthy sleep pattern, it generally takes about 90 minutes to reach REM sleep, so a significantly shorter latency can point to underlying psychological or physiological issues.

Untreated depression is commonly associated with alterations in sleep architecture, including a reduction in REM latency. Individuals experiencing depression often find themselves entering REM sleep more quickly, which may be due to the depressive state’s impact on the sleep cycle and brain activity during sleep. This phenomenon highlights the connection between mood disorders and sleep disruption, making it a primary suspect in the scenario presented.

The other options, while they can also affect sleep, tend to produce different characteristics in sleep architecture. For example, untreated anxiety may lead to increased arousal and difficulty falling asleep, while chronic insomnia is typically characterized by problems maintaining or initiating sleep, which would not produce such a short REM latency. Substance abuse can alter sleep patterns significantly but tends to create more erratic sleep structures rather than consistently shortened REM latency.