View clinical trials related to Sleep Deprivation.
Filter by:This study will measure brain activity in individuals performing language tasks while in various states of alertness to learn more about how the central nervous system is affected by impairments such as sleepiness. Healthy normal volunteers between 20 and 40 years of age may be eligible for this study. Candidates must be non-smokers, right-handed, speak English fluently and have at least 12 years of education. They are screened with a medical history, physical examination, hearing and speech evaluation, computer task training, blood and urine tests and a late-night functional magnetic resonance imaging (fMRI) scan (see description below). Before screening and again before participating in the study, candidates wear an actigraph (a wristwatch-like device that records motion) for 7 days to provide a measure of their sleep-wake patterns. Participants undergo the following tests and procedures: - Extended wakefulness: Subjects are kept awake longer than is normal for them in their everyday life to be able to examine the brain under conditions of sleepiness. They are engaged in activities with the research staff during this waking time. - Functional magnetic resonance imaging: Subjects undergo five separate fMRI scans-one during screening and four others during the main part of the study. fMRI uses a magnetic field and radio waves to produce images of the brain. The subject lies on a table that is moved into the scanner (a narrow cylinder), wearing earplugs to muffle loud knocking and thumping sounds that occur during the scanning process. Brain scans are taken at rest and while the subject performs tasks, which include pressing a button upon seeing certain shapes and performing various language tasks, such as saying memorized or new words, listening to narratives, and describing everyday procedures. - Neurological, speech-language, and neuropsychological testing: Before the fMRI exams and during the period of extended wakefulness, subjects complete a series of tests that measure speech, language, memory and visual skills. Portions of the tests may be video- or autiotaped. - Interviews and questionnaires: Participants are interviewed about their handedness, sleep history, and presence of medical or neurological symptoms. - Electrophysiological studies: Subjects have an electroencephalograph (EEG) to measure the electrical activity of the brain and surface electromyography (EMG) to measure movements of muscles involved in moving and speaking. For the EEG, electrodes (small metal disks) are attached to the surface of the scalp or to a cap placed over the head. For the EMG, electrodes are attached to the skin of the face and neck by plastic or paper tape.
This study will use positron emission tomography (PET) to examine the effect of sleep deprivation on brain function.
The primary objective of the present study is to examine whether the combination of the antidepressant duloxetine and chronotherapeutic methods (including sleep deprivation, light therapy, and maintaining a regular sleep-wake rhythm) in patient with major depression, will induce an immediate improvement from depression and whether this antidepressive effect will be maintained in the long term (29 weeks). Patient will be randomised to the above mentioned treatment or to an active group receiving exercise.
The purpose of this study is to determine whether or not a low calorie, low glycemic index diet with omega-3 fatty acid supplements can prevent some of the negative consequences of sleep deprivation.
The purpose of this study is to examine the effects of Tai Chi, in comparison to conventional exercise, on the quality of sleep among sedentary older adults.
This study will evaluate how the state of being completely deprived of sleep has an effect on recordings of magnetoencephalography (MEG) and electroencephalography (EEG), in relation to how alert someone is and how sleepy someone perceives himself or herself to be. EEG measures electronic potential differences on the scalp. On the other hand, MEG is a non-invasive technique for recording the activity of neurons in the brain, through recording of magnetic fields caused by synchronized neural currents. It has the ability to detect seizures. Because magnetic signals of the brain vary, this technique must balance two key problems: weakness of the signal and strength of the noise. The EEG is sensitive to extra-cellular volume currents, whereas the MEG primarily registers intra-cellular currents. Because electrical fields are quite dependent on the conductive properties of the tissues, and magnetic fields are significantly less distorted by tissue, the MEG has better spatial resolution. There is a great deal of evidence that EEG and MEG provide complementary data about underlying currents of ions. The complex relationship of sleep and epilepsy is well known. Sleep has been used for many years as a powerful EEG activator. Many researchers have supported the hypothesis that there is a specific activating effect of sleep deprivation on epileptic discharges. Sleep deprivation is defined as a sleepless state of longer than 24 hours. The increased use of MEG in diagnosis could improve the procedure for evaluating patients before surgery for epilepsy, by making invasive studies less necessary. Patients 18 years of age or older, with a diagnosis of epilepsy and with a documented last routine EEG (at least 2 weeks earlier) and routine EEG on the day of a baseline MEG-EEG without interictal epileptiform discharges (IEDs) may be eligible for this study. Participants will be rated according to the Epworth, Stanford, and Karolinska Sleepiness Scales, to determine their subjective sleepiness. They will be randomly assigned to stay awake all night or sleep in the hospital overnight. That is, a sleep deprivation and non-sleep deprivation synchronized MEG-EEG recording will be performed in random order. Then the sequence of sleep deprivation and non-sleep deprivation will be reversed within 14 to 21 days. During the recordings, the patient will either sit or lie with his or her head in a helmet covering the entire head, with openings for the eyes and ears. Brain magnetic fields will be recorded with a 275-channel OMEGA system. Throughout the session, visual and two-way audio communication will be maintained with the patient. Recording sessions will last 90 to 180 minutes, with the patient allowed to take breaks after at least 10 minutes in a scanner. Attempts will be made to encourage patients to stay awake and sleep for about the same amount of time during each recording, to acquire comparable amounts of sleep and awake recordings.