Problem 19 - Biological Psychology

Question

What kinds of individuals get more REM sleep than others? (Think in terms of age, species, and long versus short sleepers.)

Step-by-Step Solution

Answer

Infants, species with more REM, and long sleepers get more REM sleep.

Step 1: Consider Age

Infants and young children typically have more REM sleep compared to adults. As people age, the proportion of REM sleep generally decreases.

Step 2: Review Species Differences

Different species have distinct sleep patterns, with some animals experiencing more REM sleep than others. For example, humans tend to have more REM sleep than many other species, while some animals, like dolphins, have significantly less.

Step 3: Examine Long vs Short Sleepers

Individuals who are long sleepers generally experience more REM sleep than those who are short sleepers. This means that people who require more hours of sleep per night often have a higher amount of REM sleep in their sleep cycle.

Key Concepts

Age and Sleep

Infants and young children spend a significant portion of their sleep in Rapid Eye Movement (REM) sleep. This is the sleep phase associated with vivid dreams and essential for cognitive development. In fact, babies can spend up to 50% of their sleep time in REM.
As we grow older, the amount of REM sleep we experience tends to decrease. Adults typically spend about 20-25% of their sleep in this stage. This change is due to various factors, including alterations in brain structure and changes in sleep needs.

• Infants: Up to 50% REM sleep
• Adults: 20-25% REM sleep
• Older adults: May experience even less REM sleep

Understanding age-related changes in sleep patterns is essential for emphasizing the importance of good sleep hygiene across all ages.

Species Sleep Patterns

Different species exhibit remarkably varied sleep patterns. While humans are known for having a substantial amount of REM sleep, the same is not true for all species. Some animals, like dolphins and whales, exhibit unihemispheric sleep.
This means that one half of their brain remains awake while the other half sleeps, leading to very little REM sleep. This adaptation allows them to be partially alert and continue breathing as they swim.

• Humans: High REM sleep proportion
• Dolphins: Minimal REM sleep due to unihemispheric sleeping
• Dogs and cats: More similar to humans with notable REM phases

Recognizing the diversity in species sleep sheds light on how different physiology and environmental needs impact sleep.

Long vs Short Sleepers

People's sleep needs can vary widely, making them either long sleepers or short sleepers. Long sleepers tend to need more than the typical 7-9 hours of sleep a night. This additional sleep often means they enjoy more REM sleep compared to their short sleep counterparts.
In contrast, short sleepers might sleep less than 7 hours yet feel just as rested, but they typically experience less REM sleep.

• Long Sleepers: More than 9 hours of sleep, significant REM sleep
• Average Sleepers: Around 7-9 hours of sleep with a balance of sleep stages
• Short Sleepers: Less than 7 hours, less REM sleep

Understanding these differences is important for recognizing why some people need more or less sleep and how it affects their REM cycles.