The Sleep Monitoring Lab, directed by Rebecca Spencer, is part of the Human Testing Center within the Life Science Laboratories. It houses three bedrooms and a central control room for observing sleeping participants. To measure sleep, the Lab uses polysomnography (PSG), a montage of recordings of brain through electroencephalography (EEG), eye movements through electrooculography (EOG), and muscle activity through electromyography (EMG). A person’s heart rhythm can also be recorded using an electrocardiogram (EKG). This combination of information allows researchers to characterize sleep into one of four stages: non-REM stages 1, 2, 3 and REM (rapid eye movement).
Developmental Science graduate student, Sanna Lokhandwala, is leading a project examining the role of sleep on learning and memory in preschool-age children. ”Considering that midday naps are characteristic of early childhood, little is understood about the function of these sleep periods. Our lab has shown that there is a benefit of a nap on visuo-spatial memory. Specifically, we have shown that following a nap, performance on a visuo-spatial learning task is improved in preschool-aged children. Further, there is a relationship between sleep physiology and the nap-dependent performance benefit,” says Lokhandwala.
Nap-dependent changes in performance were associated with sleep spindles (bursts of oscillatory brain activity that occur during stage 2 non-REM sleep). The researchers want to know whether this performance benefit following the nap generalizes to other tasks using declarative memory (facts or events that can be recalled).
Lokhandwala explains, “Our study involves children from 3-5 years old. Children and their families come into our sleep lab where, after getting them acquainted with the space, the experimenter reads the child two novel storybooks (created in the lab) that describes an activity or event. Right after, children engage in immediate recall where they are given cards depicting scenes from the story and are asked to place the cards in the correct order without any feedback.”
For more information or to participate in this study, email firstname.lastname@example.org or call 413.545.4831.
Another interest of the lab is to improve sleep measurement. By evaluating the validity of commercial devices that measure sleep, ways to improve these measures can be considered. The lab sets up a participant with their PSG system using an ambulatory sleep data amplifier/recorder. They also use respiratory inductance plethysmography (RIP) belts over the thorax and abdomen measuring respiratory effort, and a nasal cannula measuring respiratory flow with accompanying thermistors measuring heat. A pulse oximeter on the finger measures pulse and blood oxygen saturation.
The system is then run simultaneously to a FitBit or similar device placed around the subject’s wrist. The researchers want to know how precise these health monitoring devices are, and if they actually perform the way they are intended. These devices typically record data to a smartphone app, allowing consumers to measure their progress towards health-related goals.