ALBANY — The state Health Department has revoked the medical license of a physician who conducted human brain-activity experiments and other unsanctioned research on people associated with the NXIVM corporation.

Brandon B. Porter, who has been involved with NXIVM for many years, was served with 25 misconduct charges by the state Health Department's Office of Professional Medical Conduct in April 2018, a month after NXIVM leader Keith Raniere was arrested and charged with multiple federal crimes, including sex trafficking. The board that reviewed his case sustained 24 of the charges.

In June, at the end of a two-month trial, a federal jury in Brooklyn convicted Raniere, 58, of all the charges he faced, including racketeering acts of identity theft, obstruction of justice, wire and visa fraud, forced labor, human trafficking, money laundering, child exploitation and possession of child pornography.

Porter, 45, who attended medical school at the University of Iowa, has been living in a Waterford residence owned by NXIVM associates and working in a private sector job. His license to practice medicine was suspended when he was served with the misconduct charges last year.

The Times Union reported Porter's license revocation Thursday afternoon. The health department later posted its decision on its website.

The newspaper reported in October 2017 that Porter had not published a scientific study in years and there was no indication his private research was being overseen by an independent review board. That same month, Porter abruptly resigned from his job at St. Peter's Hospital in Albany.

The state's scrutiny of Porter was revived after a federal criminal investigation of NXIVM's leaders began in late 2017. The state Health Department had initially brushed off a complaint filed in August 2017 by a Vancouver, British Columbia, woman who was associated with NXIVM and said she was traumatized from a bizarre experiment in which Porter showed her videos depicting graphic violence in August 2016.

NXIVM has acknowledged it conducted human research studies, including for treatment of Tourette's syndrome, although it's unclear that any of the studies sanctioned by the company were ever published or peer reviewed.

The state charges accused Porter of gross negligence for the studies that included a "fright study" in which he would show subjects the disturbing videos while they were hooked up to a brain-activity monitoring device. The charges alleged moral unfitness to practice medicine, gross negligence, incompetence and fraud in practicing medicine, and failure to keep records and file required reports.

Internal Revenue Service records indicate a nonprofit associated with NXIVM acquired more than $145,000 worth of computers, medical equipment and brain-activity monitors several years ago.

The IRS filings indicate the nonprofit, Ethical Science Foundation, was funded at least in part by donations from Clare W. Bronfman, an heiress of the Seagram Co. business empire and the operations director of the NXIVM corporation. Bronfman pleaded guilty to federal criminal charges in April and, like Raniere, is awaiting sentencing.

Other NXIVM associates who pleaded guilty to federal criminal charges are NXIVM President and co-founder Nancy L. Salzman, her daughter, Lauren Salzman, television actress Allison Mack and NXIVM's longtime bookkeeper, Kathy L. Russell.

None of the convictions were related to the unsanctioned medical studies carried out by Porter.

A 2015 IRS form filed by the nonprofit listed its "charitable activities" as "Tourette's study — studying the effects of a specific and innovative method has on individuals with Tourette's syndrome and obsessive compulsive disorder." The 2015 tax form said its expenses were $32,620.

The state attorney general's office filed a court petition in March 2018 asking a judge to order Bronfman and Porter to turn over their records related to the studies. The attorney general's office subsequently suspended its probe later that month when Raniere was taken into custody in Mexico and turned over to U.S. authorities.

Jennifer Kobelt, an aspiring actress who was part of NXIVM until June 2017, said in 2017 in a complaint to the health department — and in an interview with the Times Union — that Porter showed her disturbing videos during an August 2016 session in a commercial building in Halfmoon regularly used by NXIVM to host training seminars and other events.

Kobelt told the Times Union that Porter seated her in front of a television and attached electrodes to her scalp before putting what Kobelt said NXIVM associates called the "brain cap" on her head.

Kobelt said wearing the brain cap was not unusual: She and others had often allowed Porter to monitor their brain activity, usually when they were watching videos of lectures by Raniere.

Porter took notes on a laptop while he showed Kobelt a scene from the 1998 drama "American History X" in which a black man is stomped to death by a neo-Nazi, the brutal gang-rape scene from the Jodie Foster film "The Accused," a film clip in which a conscious man is forced to eat part of his own brain, and what appeared to be footage from an actual mass murder: women being decapitated and dismembered, seemingly by members of a drug cartel.

Kobelt, who said she was told up to 100 people had taken part in the same study, said no one told her what the study was for or what to expect, nor did she sign documents acknowledging she had been informed of the details of the study or its purpose, or that she was consenting to taking part.

In response to the complaint that Kobelt filed with the state Health Department, the agency initially sent her a letter saying that what she described was "not medical misconduct."

When asked in 2017 about its standards for human brain studies, an agency spokesman said: "In cases where a study of human brain activity involves the practice of medicine, the physician conducting the study must comply with all standards of professional medical conduct, including the laws regarding informed consent."

The Health Department's investigation of Porter's conduct was revived by the agency after the governor's office reviewed their handling of the complaint.

The disciplinary charges against Porter also cited him for similar violations for studies on obsessive-compulsive disorder and Tourette's syndrome conducted between 2012 and 2017, and for brain-wave studies in 2015 and 2016 related to classes, coaching, training and so-called professional-advancement courses offered by NXIVM and its affiliated Executive Success Programs.

Porter was also accused of failing to report to authorities that, during a NXIVM conference at a Lake George facility in late summer 2016, many of the 300 to 400 attendees, including 50 to 60 children, became ill with an "undetermined infectious disease" with flu-like symptoms, vomiting and diarrhea. As a licensed medical doctor, Porter was obligated to report the outbreak.

The Times Union first reported in April that another physician who branded multiple women with the initials of Keith Raniere is the target of an investigation in which state officials have waged a court battle to compel eight people associated with NXIVM to testify in the case.

The Health Department's efforts were outlined in a state Supreme Court case filed last year against eight "Jane Does" who allegedly were involved in — or had knowledge of — the secret branding ceremonies.

The court case confirms that Dr. Danielle D. Roberts, 37, an osteopath and former Clifton Park resident who had been associated with NXIVM, is being investigated for "allegations of professional medical misconduct."

The state Health Department's Office of Professional Medical Conduct served subpoenas on the women in January 2018, setting off a 10-month legal battle. Attorneys for the NXIVM associates, including Lauren Salzman, who is the daughter of NXIVM President Nancy Salzman, tried unsuccessfully to convince a judge to revoke the subpoenas.

The status of Roberts' case could not immediately be confirmed on Thursday.