Non scarring hair loss, also known as noncicatricial alopecia is the loss of hair without any scarring being present. There is typically little inflammation and irritation, but hair loss is significant. This is in contrast to scarring hair loss during which hair follicles are replaced with scar tissue as a result of inflammation. Hair loss may be spread throughout the scalp (diffuse) or at certain spots (focal). The loss may be sudden or gradual with accompanying stress. The most common cause is androgenetic alopecia, also known as male pattern or female pattern hair loss due to the effects of dihydrotestosterone (DHT) on the hair follicles. A variety of factors may lead to this condition such as hormonal effects, age, diet, autoimmunity, emotional stress, physical stress, drug effects, genetics, or infections. Depending on the cause, treatment options include: topical minoxidil, oral finasteride, anti-fungal medications, steroids, hair transplantation, or platelet rich plasma (PRP) therapy. Alternatives for total hair loss include the use of hairpieces or hair fibers. Signs and Symptoms
Patients will notice either focal or diffuse loss of hair. This may occur due to thinning or shedding of the hair over a sudden or gradual period of time. Stress may be present, and the emotional impact of hair loss is important as it may cause significant distress. Other signs may point to specific causes of the condition. Poor diet may lead to tiredness, other side effects of chemotherapy drugs may be seen, infection can cause itching, stress may lead to pulling of hair or falling of hair.
Furthermore, rumination and poor coping resources may play a significant role in sleep misperception. Spectral analysis
According to a May 2014 article published in New Scientist, spectral analysis may help clinicians find objective evidence for sleep state misperception:

[...] it uncovered [...] subtle differences in the EEGs of sleeping insomniacs: alpha waves – signatures of wakefulness that are supposed to show up only in early sleep – were intruding into deep sleep. [...] [psychologist and sleep researcher Michael] Perlis. But Andrew Krystal of Duke University in Durham, North Carolina, used spectral analysis to quantify just how much they were intruding. Krystals non-sleepers not only had a greater proportion of these alpha disturbances, but the alpha waves were bigger and the delta waves were correspondingly smaller. That wasnt all. When Perlis and other researchers applied spectral analysis algorithms to the EEGs of their sleeping insomniacs, they found different patterns, fast waves known as beta and gamma (Sleep, vol 24, p 110). Normally, these are indicators of consciousness, alertness and even anxiety [...] Like alpha waves, Perlis calls these beta and gamma waves "intrusions" into normal sleep: "Its as if somebody is playing with the switch – boop, boop – flipping at a mad rate between wake and sleep". Distinction from insomnia
What is considered objective insomnia, unlike SSM, can easily be confirmed empirically through clinical testing, such as by polysomnogram. Those who experience SSM may believe that they have not slept for extended periods of time, when they in fact do sleep but without perceiving it.