Sleep deprivation, whether total or not, can induce significant anxiety and longer sleep deprivations tend to result in increased level of anxiety.Sleep deprivation has also shown some positive effects on mood, and can be used to treat depression. Chronotype can affect how sleep deprivation influences mood. Those with morningness (advanced sleep period or "lark") preference become more depressed after sleep deprivation while those with eveningness (delayed sleep period or "owl") preference show an improvement in mood.Mood and mental states can affect sleep as well. Increased agitation and arousal from anxiety or stress can keep one more aroused, awake, and alert. Driving ability
The dangers of sleep deprivation are apparent on the road; the American Academy of Sleep Medicine (AASM) reports that one in every five serious motor vehicle injuries is related to driver fatigue, with 80,000 drivers falling asleep behind the wheel every day and 250,000 accidents every year related to sleep, though the National Highway Traffic Safety Administration suggests the figure for traffic accidents may be closer to 100,000. The AASM recommends pulling off the road and taking a 15- or 20-minute nap to alleviate drowsiness.According to a 2000 study published in the British Medical Journal, researchers in Australia and New Zealand reported that sleep deprivation can have some of the same hazardous effects as being drunk. People who drove after being awake for 17–19 hours performed worse than those with a blood alcohol level of 0.05 percent, which is the legal limit for drunk driving in most western European countries and Australia.
Others report that methyl mercaptan was the greatest contributor to the odor of flatus in patients not under any specific dietary alterations. It has now been demonstrated that methyl mercaptan, dimethyl sulfide, and hydrogen sulfide (described as decomposing vegetables, unpleasantly sweet/wild radish and rotten eggs respectively) are all present in human flatus in concentrations above their smell perception thresholds.It is recognized that increased dietary sulfur-containing amino acids significantly increases the odor of flatus. It is therefore likely that the odor of flatus is created by a combination of volatile sulfur compounds, with minimal contribution from non-sulfur volatiles. This odor can also be caused by the presence of large numbers of microflora bacteria or the presence of faeces in the rectum. Diets high in protein, especially sulfur-containing amino acids, have been demonstrated to significantly increase the odor of flatus. Volume and intestinal gas dynamics
Normal flatus volume is 476 to 1491 mL per 24 hours. This variability between individuals is greatly dependent upon diet. Similarly, the number of flatus episodes per day is variable; the normal range is given as 8–20 per day. The volume of flatus associated with each flatulence event again varies (5–375 mL). The volume of the first flatulence upon waking in the morning is significantly larger than those during the day. This may be due to buildup of intestinal gas in the colon during sleep, the peak in peristaltic activity in the first few hours after waking or the strong prokinetic effect of rectal distension on the rate of transit of intestinal gas.