Patients who suspect they might have a sleep disorder should speak with their primary care physician, who might want to order a sleep study and/or a consultation from our staff of sleep experts.

Our Physicians

Meet our physicians

Conditions We Treat

Sleep Apnea

Sleep Apnea is a breathing problem in which the soft tissues in the throat close down for about 20-30 seconds at a time during sleep. With each pause in breathing, the brain “wakes up” just enough to start breathing properly, although the person may or may not be aware that these obstructions are occurring. Many people have some pauses in breathing when they sleep. We diagnose Obstructive Sleep Apnea (OSA) when we count at least 5 pauses in breathing per hour of sleep. The more pauses there are, the more severe is the case of Sleep Apnea. Patients who have an overnight sleep study (PSG) are given a number or index of how many pauses occurred per hour of sleep. It is important to ask your doctor how to interpret this number (the "AHI").

Dr. Adusumilli is brilliant and kind and extremely has a wonderful bedside manner, very knowledgeable and I couldn't recommend her more highly. I have sleep apnea and I've seen her over the course of several years and she's a wonderful researcher as well. And I feel very confident that I am getting the best care possible through her.

— patient in the Division of Sleep Medicine
More patient feedback

Circadian Rhythm Disorders

Our internal “clock” is located in a small part of the brain called the suprachiasmatic nucleus (SCN). For most people, the clock runs on a cycle that is just slightly longer than 24 hours and is synchronized with the light-dark cycle. In fact, light detected by the eyes entrains the clock by sending signals to the SCN. However, for some people the clock does not synchronize properly, causing the person to feel sleepy before or after “normal” bedtimes. In teenagers and young adults, the most common circadian rhythm disorder is called delayed phase (staying up late and then sleeping late the next morning), while in older adults the advanced phase pattern is more likely (early to bed, early to rise). These patterns can cause difficulty when the person’s social or work schedule is not compatible with the timing of the internal clock. Fortunately, the clock can be entrained to change – this happens when we cross time zones: the clock reacts to light as well as other clues (food, social activity, exercise).


People with insomnia may report difficulty falling asleep or staying asleep. Many factors can lead to insomnia symptoms, ranging from stress or caffeine to pain or medical problems that interrupt sleep. For some people, simple tips known as sleep hygiene are enough to improve sleep. But for others, the situation can be more complicated. Some patients have such negative experiences with sleep that they actually get caught in a cycle: each night, the idea of trying to sleep itself causes stress which then makes it harder to sleep. 

Insomnia is divided into many subtypes, in part because the suggested treatments may differ depending on the individual case. It is important to note that beliefs about what is “normal” sleep can impact whether a person seeks treatment. For example, some people think that it is abnormal to awaken during the night, or that they need 8 hours of sleep per night to be healthy. Although sleep is certainly important, individual needs vary greatly. Thus, failing to meet general expectations can cause anxiety (which can impact sleep!), and make a person feel like they have a problem or that they need to take medication. To make things even more challenging, people with insomnia may be sleeping more than they think. 


For a small portion of patients who are sleepy during the day, the problem is a neurological disorder called narcolepsy. In addition to feeling sleepy, patients with narcolepsy often have other symptoms, like feeling paralyzed for a minute or so when they wake up, or having dream sensations as they are about to fall asleep but are still awake. In about half of patients with narcolepsy, cataplexy may occur: weakness of part of the body (or the whole body) that is triggered by laughter or strong emotion. Patients experiencing cataplexy spells are awake – these “attacks” are different than fainting or a seizure, where the person loses consciousness.


Some people engage in various vocal and/or movement behaviors in their sleep. These sleep disorders are known as parasomnias. Sleepwalking and sleep talking mainly occur during non-REM (NREM) sleep and represent NREM parasomnias.

Some patients “act out their dreams.” These dreams have usually negative and aggressive emotional content. Dream enactment can occur due to a loss of normally present muscle paralysis during REM sleep. This parasomnia is known as REM Sleep Behavior Disorder (RBD), as it occurs during REM sleep. Besides its negative impact on sleep quality and potential safety implications, RBD is of particular significance as individuals who have the disorder may be at an increased risk for the development of neurodegenerative disorders such as Parkinson’s disease and dementia.

Restless Legs Syndrome (RLS)

Some people experience uncomfortable sensations in their legs, especially at night or if they sit for long periods, when they feel an urge to move or stretch. The symptoms of RLS can range from being barely noticeable and not requiring any treatment, to being very bothersome that it makes it hard to fall asleep. RLS may not be limited to night-time; it can also happen any time a person is sitting still, like in a car or movie theater. RLS is different from the brief muscle twitches that occur as we fall asleep (which are called “hypnic jerks”). A sleep study is not needed to diagnose RLS; the diagnosis is based on eliciting symptoms that patients experience through a clinical interview. For some patients, treatment can simply involve keeping hydrated and stretching before bed. Low iron levels can play a role, which can be treated with oral iron tablets (taken with Vitamin C, between meals, to aid absorption). Prescription treatments are also available.

Many patients with RLS symptoms also have leg movements during sleep, known as periodic limb movements of sleep. Patients may not even realize they have these movements, but their bed partner may notice them.


Subspecialty Sleep Clinics

REM Sleep Behavior Disorder (RBD) Clinic
RBD is a parasomnia characterized by dream enactment. Besides being a sleep disorder, RBD has been recognized as an important prodromal manifestation of certain neurodegenerative disorders, such as Parkinson’s disease and some forms of dementia. In our RBD clinic we provide diagnostic counseling and comprehensive management of individuals affected with RBD. Our RBD patients have an opportunity to join the North American Prodromal Synucleinopathy Consortium (NAPS). For more information, please visit

Restless Legs Syndrome (RLS) Clinic
The Division of Sleep Medicine is home of a dedicated clinical and research program on RLS. Our patients have an opportunity to get sub-specialized clinical care for RLS, and participate in clinical trials.

Sleep in Neurodegenerative Disorders Clinic
Sleep disorders are common manifestations of neurodegenerative disorders such as Parkinson’s, Alzheimer’s and Huntington’s diseases. These symptoms are frequently under-reported by patients and under-recognized by clinicians. In this clinic, we provide dedicated care to individuals affected with these neurodegenerative disorders who have co-existent problems with sleep and alertness.

Neurophysiological Diagnostic Services at the Sleep Lab

The Division of Sleep Medicine's sleep laboratory features an eight-bed diagnostic center for testing outpatients. For comfort and convenience, it is located at the Wyndham Hotel, immediately next to Mass General. As we tell our patients, coming to the sleep lab is similar to checking in to a hotel.

This state-of-the-art facility allows us to safely and efficiently administer overnight testing in the form of sleep study called a polysomnogram. We also perform daytime testing, including the multiple sleep latency test, or MSLT, as well as mask fitting and desensitization. All of our facilities are wheelchair-accessible. We can accommodate children age 13 and above for overnight testing.

Mask Fitting/Desensitization Clinic
This option involves a usually brief (under 30 minutes) visit by appointment with our sleep technologists during business hours to optimize the mask interface. It may be a useful intermediate step for those having difficulty tolerating their mask at home, before needing to repeat an overnight titration study.