Sleep and Cognition

On this page, we summarize our current research projects on the topic of Sleep and Cognition. We specifically investigate:

  • The relationships between sleep neurophysiology and age–related cognitive decline.
  • The combined effects of nap and exercise on cognitive performances.
  • The cognitive impacts of sleep deprivation and sleep disorders.

Nap, exercise and cognition

Combined effects of short-term exercise and sleep on recognition memory in healthy, young sedentary adults

Summary

Healthy lifestyle factors such as proper amounts of sleep and exercise are important for cognitive function. Research has provided evidence for the beneficial role of short-term exercise in enhancing memory and improving sleep quality.  Even a brief daytime nap has been linked to improvements in memory for recalling items and recognizing events. Little is known about the effects of moderating factors. The aim of this study is to decipher if the joint effects of sleep and physical activity goes above and beyond the improvement conveyed by sleep or exercise alone.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.

Fragmentation of the rest-activity cycle in young, adult nappers using a novel fragmentation metric

Summary

Napping has been shown to provide a variety of benefits such as improvement in mood, alertness and performances. In some cases, naps can also be detrimental. The number of naps, nap length or proximity of a nap to sleep periods may result in poor quality sleep. The aim of this study is to determine whether a novel fragmentation metric can be used as a successful measure of sleep disruption. And to determine if napping behaviors are related to nighttime sleep dysfunction.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.

A comparison of self-perceived sleepiness reports with brain activity measures on cognitive performance

Summary

Testing alertness by measure of electrical brain activity has been shown to be a better indicator of sleepiness than subjective self-reports. Sleep pressure builds up during wake and is decreased during sleep. Recently, researchers have identified markers of sleep pressure in the waking EEG brain waves. For example, it has been shown that increasing time awake is associated with increasing time spent in a specific EEG frequency range, theta/low frequency alpha activity (TLFA spectral power: 5.25 to 9.0Hz). TLFA frequency range has been reported elevated in habitual short sleepers (<7hrs/night), and in average sleepers (~8hr/night) with increasing time awake. This project evaluates subjective reports and objective brain measures of sleepiness in order to determine if there’s an influence on cognitive performance.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.

Sleep and cognition across the lifespan

Coupling of neural oscillations in sleep, in relation to cognition, aging, and Alzheimer’s disease

Summary

Sleep fulfills important adaptive functions such as maintaining good health and overall cognitive functioning. Conversely, problematic sleep is associated with poorer health and cognitive (i.e., memory) impairments. Sleep problems commonly reported among aging populations (e.g., delayed sleep onset, frequent arousals from sleep) have been associated with aberrant brain oscillation activity during sleep (e.g., reduced slow wave amplitudes, fewer sleep spindles) and with ageing-related cognitive impairments. Research examining the “cross-frequency coupling” (CFC), or phase-amplitude synchronization, of distinct brain oscillations suggests that CFC may reflect a potential mechanism through which the brain transfers information between different regions and consolidates memories. A growing theory is that age-related declines in oscillation coupling during sleep may be implicated in the pathophysiology of age-related cognitive impairments and may be an early sign of Alzheimer’s disease (AD). This research examines associations between CFC during NREM and REM sleep and performance on a sleep-dependent, declarative memory task in healthy younger and older adults, and in older adults with mild cognitive impairments and AD. The overarching goal of this research is to better understand neurological phenomena that facilitate memory consolidation processes, and to elucidate possible mechanisms underlying relations between sleep and AD pathophysiology.

Need more info?

Please contact Oren Weiner at contact@scnlab.com.
Nap, exercise and cognition

Nap, exercise and cognition

Combined effects of short-term exercise and sleep on recognition memory in healthy, young sedentary adults

Summary

Healthy lifestyle factors such as proper amounts of sleep and exercise are important for cognitive function. Research has provided evidence for the beneficial role of short-term exercise in enhancing memory and improving sleep quality.  Even a brief daytime nap has been linked to improvements in memory for recalling items and recognizing events. Little is known about the effects of moderating factors. The aim of this study is to decipher if the joint effects of sleep and physical activity goes above and beyond the improvement conveyed by sleep or exercise alone.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.

Fragmentation of the rest-activity cycle in young, adult nappers using a novel fragmentation metric

Summary

Napping has been shown to provide a variety of benefits such as improvement in mood, alertness and performances. In some cases, naps can also be detrimental. The number of naps, nap length or proximity of a nap to sleep periods may result in poor quality sleep. The aim of this study is to determine whether a novel fragmentation metric can be used as a successful measure of sleep disruption. And to determine if napping behaviors are related to nighttime sleep dysfunction.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.

A comparison of self-perceived sleepiness reports with brain activity measures on cognitive performance

Summary

Testing alertness by measure of electrical brain activity has been shown to be a better indicator of sleepiness than subjective self-reports. Sleep pressure builds up during wake and is decreased during sleep. Recently, researchers have identified markers of sleep pressure in the waking EEG brain waves. For example, it has been shown that increasing time awake is associated with increasing time spent in a specific EEG frequency range, theta/low frequency alpha activity (TLFA spectral power: 5.25 to 9.0Hz). TLFA frequency range has been reported elevated in habitual short sleepers (<7hrs/night), and in average sleepers (~8hr/night) with increasing time awake. This project evaluates subjective reports and objective brain measures of sleepiness in order to determine if there’s an influence on cognitive performance.

Need more info?

Please contact Melodee Mograss at contact@scnlab.com.
Sleep and cognition across the lifespan

Sleep and cognition across the lifespan

Coupling of neural oscillations in sleep, in relation to cognition, aging, and Alzheimer’s disease

Summary

Sleep fulfills important adaptive functions such as maintaining good health and overall cognitive functioning. Conversely, problematic sleep is associated with poorer health and cognitive (i.e., memory) impairments. Sleep problems commonly reported among aging populations (e.g., delayed sleep onset, frequent arousals from sleep) have been associated with aberrant brain oscillation activity during sleep (e.g., reduced slow wave amplitudes, fewer sleep spindles) and with ageing-related cognitive impairments. Research examining the “cross-frequency coupling” (CFC), or phase-amplitude synchronization, of distinct brain oscillations suggests that CFC may reflect a potential mechanism through which the brain transfers information between different regions and consolidates memories. A growing theory is that age-related declines in oscillation coupling during sleep may be implicated in the pathophysiology of age-related cognitive impairments and may be an early sign of Alzheimer’s disease (AD). This research examines associations between CFC during NREM and REM sleep and performance on a sleep-dependent, declarative memory task in healthy younger and older adults, and in older adults with mild cognitive impairments and AD. The overarching goal of this research is to better understand neurological phenomena that facilitate memory consolidation processes, and to elucidate possible mechanisms underlying relations between sleep and AD pathophysiology.

Need more info?

Please contact Oren Weiner at contact@scnlab.com.