Rep. Gladys N. Spellman, reelected by a landslide Tuesday despite her critical medical condition, was moved to Prince George's General Hospital and Medical Center yesterday where she will undergo extensive neurological testing in the next few days.

Spellman, 62, suffered cardiac arrest last Friday during a campaign appearance at a Laurel shopping mall. The Prince George's Democrat has been in critical but stable condition ever since, unable to emerge from a light unconsciousness, or what doctors have called "a sleep-like state."

Until yesterday Spellman was being treated at the Greater Laurel-Beltsville Hospital coronary care unit but she was moved because that hospital does not have the complex medical equipment -- in particular an X-ray device called a CAT scanner -- that doctors felt might shed some light on her neurological condition and the causes of her semicoma.

Spellman's heart and other organs such as her kidneys have been functioning normally since her collapse and yesterday her cardiologist, Michael Schwartz, said that Spellman would soon be taken off a respirator that has been helping her breathe.

Schwartz also said that in the last few days the three-term representative has shown further slight-signs of possible improvement -- wrinkling her forehead, moving her arms and legs, making a fist and opening her eyes -- in response to tests.

"She's making progress, there's no doubt about it," he said. "As long as she's making progress, she could recover." Although it is possible that her recent physical activity could be merely reflex responses to the sometimes painful tests, Schwartz said he felt they signaled brain activity.

Spellman's neurological condition has been the unknown factor since her collapse and the cause for grave concern among her friends, physicians and associates.

Although Spellman was immediately given cardio-pulmonary resusciation when she collapsed, an ambulance and rescue squad with equipment and medication necessary to restore a strong heartbeat did not arrive for 16 to 20 minutes according to accounts of witnesses.

If Spellman's heart stopped beating for more than a few minutes, depriving her brain of oxygen, or the efforts at resuscitation were able to restore only faint pulse, it is possible that she suffered brain damage, in which case Spellman could continue in her present condition indefinitely.

Because Spellman has been in a semiconscious state, doctors have not yet been able to determine whether such damage occured. They hope to do so in the next few days through the more extensive neurological tests that are available at Prince George's General.

The two tests that will be performed within the next day or so, according to Schwartz, are an electrocephalogram (EEG), which monitors electrical activity of the brain or brain waves, and computerized cross-sectional X-rays of her brain called CAT scans. These X-rays will show whether there has been swelling, bleeding or stroke impairment of Spellman's brain.

These tests should indicate whether Spellman, who after 18 years in elective office has become the doyenne of the Prince George's Democratic establishment, will be able to recover and serve the fourth term in Congress to which she was elected with 80 percent of the vote this week.

If Spellman is unable to serve out her fourth term, Maryland Gov. Harry Hughes will be required to call a special election to replace her, although he can do that only if Spellman dies, resigns her seat, or is declared incapacitated.

If a special election is held, it will include a primary for each party, to be held not less than 35 days after Hughes' announcement, and a general election at least 35 days after that.

According to Gary Alexander, chairman of the county's Democratic Central Committee, the party has not even considered replacing Spellman. "We're not taking any action and since we expect her to recover, we don't expect to be taking any action," he said.

In the last two years, Spellman has emerged as the party's major figure in the county, and her possible removal from the county's political scene would be certain to create a massive scramble in both parties.