When researchers at Drexel University subjected volunteers to short Taser shocks and then tested for cognitive impairment, they found some study participants showed short-term declines in brain functioning -- dysfunction on par with dementia.

Scientists say the results -- detailed in the journal Criminology and Public Policy -- call into the question the legitimacy of police questioning in the immediate aftermath of an arrest involving the use of a Taser.

"The findings of this study have considerable implications for how the police administer Miranda warnings," lead study author Robert J. Kane, a professor of criminology and justice studies at Drexel, said in a news release.

"If suspects are cognitively impaired after being Tased, when should police begin asking them questions?" asked Kane. "There are plenty of people in prison who were Tased and then immediately questioned."

Kane says he and his colleagues felt a moral obligation to learn more about a subject's ability to comprehend and appreciate their due process rights in the wake of being Tased.

As part of the study, participants underwent several layers of screening to uncover previous drug use as well as cardiac and psychiatric problems -- any potential factor that might compromise a person's health during the experiments. All the chosen volunteers were high-functioning, healthy, young people.

The volunteers who were cleared to participate were made to take a series of cognitive tests in order to establish baseline cognitive performance. Next, researchers subjected different groups of participants to various circumstances before being tested again.

Some did nothing, others hit a punching bag to replicate the heightened physical state of a tussle and arrest, some received 5-second Taser shocks and others both punched and were Tased.

When retested, the average scores on memory and verbal tests for those who were Tased went down. Those who were Tased also reported difficulty concentrating, higher levels of anxiety and feeling overwhelmed.

"Being shocked had a traumatic effect on some participants," said Kane. "Some were emotionally debilitated by the experience."

Kane and his colleagues say their study suggests police departments need to begin a public conversation about how to properly integrate the use of Tasers into their routines without jeopardizing the constitutional rights of those Tased and arrested.

"The findings from this study suggest that people who have been shocked with a Taser may be unable to understand and rationally act upon his or her legal rights, and may be more likely to waive their Miranda rights directly after Taser exposure," Kane said.