Morningness-Eveningness and Performance
One line of our research investigates differences between Morning types and Evening types in levels of efficiency that occur for various types of cognitive and physical performance depending upon the time of day. Performance levels change throughout the day and reach an optimal or best time around the same time each day. This optimal functioning time is significantly influenced by chronotype status. Because performance accuracy often requires precise timing, we are investigating the influences of chronotype on time perception and the ability to accurately determine intervals of time.

Sleep Deprivation
We also study sleepiness and circadian performance decrements in cognition and performance. We are interested in both acute sleep loss ("pulling an all-nighter") and chronic partial sleep loss (daily insufficient sleep). One area of study investigates acute sleep deprivation effects on speech and how speech might be used to detect sleepiness. Another area of study is chronic partial sleep deprivation of older adults due to poor sleep. Here we are attempting to characterize the factors that cause unwelcomed sleep disruptions and inadequate sleep in adults as they become older and ways that older adults cope with these sleep disruptions. Finally, we collaborate with mechanical engineers in the College of Engineering to study effects of fatigue and time of day on driving performance.

We use perceptual, behavioral, and neuroscience methods to study these circadian and sleep-deprivation effects.