After more than 48 sleepless hours, yesterday was the first day for many Interfraternity Council/Panhellenic Dance Marathon dancers to catch up on much needed sleep.

Some dancers faired better than others, but all of them ended up sleep deprived.

Anne Hibbard (sophomore-material science and engineering) said she did not have many problems she could recall except for losing her voice.

"Keeping my feet moving really helped," Hibbard said. "Friends visiting me kept me awake."

Some dancers did not fare as well.

Ben Sipprell (sophomore-meteorology), Hibbard's dance partner, said he had to miss his first two classes and an evening exam yesterday.

"I had difficulty concentrating in class," Sipprell said. "I didn't have the sense to (take notes).

"Words didn't make any sense," he added.

Sipprell said he had problems holding objects in his hands without them shaking. "There needs to be a day to get back into the mode," Sipprell said.

Sipprell's problems are not uncommon.

Nancy Records, assistant professor in communication disorders, has done three years of research on dancers in Thon from 1996 to 1998.

"The impetus for this research was in aphasia — a language loss after a stroke," Records said. "Physically, a person shows some paralysis or weakness.

"Mentally, a person has trouble with finding words or speaking," she added.

Aphasia is not just a language disorder, but a high level disorder called resource allocation, Records said.

Resource allocation refers to the mental energy people have to accomplish a number of tasks either separately or in coordination. People begin to need more of this energy when they are stressed, tired or dividing attention between different tasks.

"People do not have enough energy and start making mistakes," Records said.

Thon has a number of elements that can affect the dancers, Records said. Crowds, fatigue and noise can lead to people to make an increased number of mistakes.

The first test in 1996, testing oral word association and sentence repetition between sleep deprived dancers and people who were not dancing, did not reveal any significant differences between dancers and non-dancers, Records said.

The second test in 1997 was intended to be more challenging and revealed subjects who either fared well or did poorly in the test, she said.

Conducted at 6 a.m., Records and her group tested a number of dancers.

"Some did quite well," Records said. "They appeared to have gotten a second wind."

Others did not.

"Some cried. Some hallucinated," she said.

A number of dancers were tested again after Spring Break.

"They did not recall being previously tested and had no recollection of ever being tested," she said.

Records said she used the hardest tests she could find for her third year of Thon researching.

Dancers were told a short story, asked to repeat it once and then again 15 minutes later, Records said. The majority of the subjects could not recall the story.

"Basically, they fell apart," she said.