Students often choose classes, football games and late night trips to Canyon over hours of sleep during the week.

These choices create sleep-deprived students with distorted voices.

Professors Frederick Brown (Psychology), Robert Prosek (Communication Disorders) and Research Associate Cynthia LaJambe (Pennsylvania Transportation Institute) are conducting an ongoing study using spectrographic analysis of voice to determine the extent of sleep deprivation.

"We used sleep-deprived students and listened to them speak at different times of the day," Brown said. "We would have them count, read a prose passage, and test reaction times."

The study hopes to determine a voice threshold that indicates the person is sleep-deprived and not functioning at optimal capacity, Brown said.

Determining the effects of sleep deprivation on voice could help NASA, the Federal Aviation Association, the military and long-distance truck drivers to monitor the ability of their employees, LaJambe said.

"A recent study at Harvard showed that when medical residents are awake for 36 hours they can make up to five times as many mistakes with patients," Brown said. "They are basically impaired like they are drunk."

Sleep deprivation is defined as a lack of sleep causing lack of normal function and awareness, Gary Barton, neurotechnician at Mount Nittany Medical Center, said.

"Your health will decline and maybe weight loss at first," Barton said. "Eventually it can lead to seizures, but this is only seen in extreme adult cases."

Besides affecting performance such as delayed reaction and voice fluctuations, sleep deprivation can

have increasingly serious health effects, Brown said.

The popular all-nighter, which suppresses the immune system, can cause students to be more vulnerable to common colds, he said.

Brown also said athletes need to be particularly careful as they do not perform at their peak physically if they are continuously sleep-deprived.

"Obesity is also correlated with lack of sleep," LaJambe said. "The less sleep you get, the more you crave sugar and are constantly eating, trying to keep yourself awake while studying all night."

The lack of sleep wears down the mechanism to control metabolism, she added.

Naps longer than 20 minutes are counterproductive, Brown said.

"Longer naps can shift the body into primary sleep mode and after an hour or more a person will wake up groggy," he said. "That is not a power nap."

If students are napping more than 20 minutes they need to sleep longer at night, Brown said.

"You can't replace daytime sleep with nighttime sleep," Brown said. "If you try, you'll be less functional during the day."

Everybody has a continuous circadian rhythm that reflects the time of day, LaJambe said. Sleeping during the day is not "in sync" with people's circadian rhythms and will not give a person 100 percent performance, she added.

A potentially more serious problem than pulling the occasional all-nighter is the usual sleep pattern of most students that can be less than 8 hours, LaJambe said. This partial sleep loss builds up a sleep debt that can not be made up just by sleeping longer on the weekend, she said.

"No one knows how long the body takes to recover," LaJambe said.

LaJambe used this example from recent research findings: after several days of sleeping five hours or less, a person will function on a significantly lower level; after two nights of eight hours or more of sleep, the person has still not recovered. More seriously, most people are not aware they are functioning at a lower level, she said.

"We don't do a good job assessing our sleep deprivation," LaJambe said. "Just like we don't do a good job assessing our impairment after a few drinks."

For this reason, LaJambe said students should sleep for a solid eight hours after finals before driving home.

Students should also avoid caffeine before going to bed, LaJambse said.

"Caffeine has a half-life of 3 to 6 hours, so a lot of it is still in the body at bedtime" LaJambe said. "The last time a person should have caffeine is at dinnertime."

Caffeine suppresses the restoring sleep everybody needs, making people feel groggy and tired when they wake up, she added.

Neither LaJambe nor Brown tells students to completely drop the caffeine if they need it.

"If people have to stay up, the best way is to take small amounts of caffeine every few hours," LaJambe said.

"Avoid tall or grande coffees with lots of caffeine," Brown said. "Share a coffee with a friend."

Headaches are a common side effect when sleep-deprived people become too dependent on caffeine and abruptly stop using it, Barton said.

Barton said a routine of eating well, exercise before six and a consistent bedtime will prevent these headaches and sleep deprivation.