Question:

Is it possible to fall asleep not for very long,dream,then wake up confused, all the time with your eyes open-and continuing to drive a motor vehicle.

Answer:

The short answer to your question is yes, it is possible. You may be describing a version of either micro-sleeps or automatic behaviors, though further details will be needed to determine which of these you may be experiencing. Both tend to occur in situations of excessive sleepiness.

Micro-sleeps are brief (often just a few seconds) of sleep during which the individual dozes off, usually without being aware of it, and awakens abruptly, sometimes confused. Recall of dream-like activity would only occur if you fell straight into REM (or dream) sleep, which can occur in some situations.

Automatic behaviors occur in situations of extreme sleepiness where the individual’s brain disengages from the surrounding the environment briefly (i.e. may fall asleep), but the individual may appear to be awake and can continue to perform some activity in an automatic or semiautomatic manner, usually without recall.

Sleeping with the eyes open, even briefly, can occur with normal sleep (and thus in micro-sleeps) or with automatic behaviors. Somewhere between 4-20% of the population does this, though it most frequently seen in children.

The situation you are describing in your question suggest you may be suffering from excessive daytime sleepiness. Excessive daytime sleepiness (EDS) is often most notable in situations where you are not being actively stimulated, such as when driving. As a result, those who are suffering from EDS are at risk for accidents. EDS has many causes and these can be broadly categorized into primary sleep disorders and problems that can affect your sleep that are not sleep disorders per se.

The most common cause of EDS is insufficient total sleep time or a lack of adequate sleep. Not sleeping enough hours (a condition called sleep restriction) can lead to excessive sleepiness during the day and is easily fixed by increasing your sleep time.

In terms of sleep disorders, there are conditions that can fragment your sleep during the night such that the sleep quality is poor and this can lead to daytime sleepiness. The most common of these sleep disorders is obstructive sleep apnea (OSA). This is a condition where the upper airway behind the tongue and soft palate is narrowed so that when the person falls asleep, the airway may partially or completely close off. Risk factors for OSA include being overweight, having a thick neck size (17 inches or greater in males and 16 inches in females), being male gender, and being older (over the age of 60). However, individuals not meeting these criteria can have OSA as well. There is often a history of loud snoring during sleep, choking or gasping at night, witnessed apneas (bed partners see the lack of breathing), and unrefreshing sleep. OSA is diagnosed with an overnight sleep study (polysomnography or PSG).

Another sleep disorder that causes sleepiness is called narcolepsy. This is a condition where a person may sleep through the night though often has very fragmented sleep. They generally feel refreshed when they wake up but become sleepy again a few hours later. Naps may help the person feel refreshed. There are other symptoms that may go with this condition such as sleep paralysis (person wakes up with a sensation that they can’t move), hypnagogic hallucinations (seeing images from dreams as one is falling asleep) and cataplexy (muscle weakness or loss of muscle tone with extreme emotions – particularly laughter). Automatic behaviors are another common associated symptom of narcolepsy. Narcolepsy is diagnosed with a sleep study where you sleep overnight (PSG) and then stay for a series of naps the next day (multiple sleep latency test or MSLT).

Aside from these conditions, numerous other factors may influence the quality of your sleep. These can range from the environment you sleep in (i.e. too warm, too loud) to your other medical problems (i.e. heartburn or breathing problems) to medications you may taking. Fragmented sleep from any of these conditions can lead to daytime fatigue and sleepiness. Depression can also cause people to feel sleepy during the day and needs to be considered.

As you can see, there are a number of possible explanations for your symptoms and it would best to undergo a thorough evaluation to determine how best to proceed. You should probably discuss this problem with your primary care physician first and then seek the opinion of a Sleep Specialist if needed. In the meantime, you should avoid driving if sleepy so as not to put yourself and others at risk for an accident.

For more information:

Go to the Sleep Disorders health topic.