TIME Health For more, visit TIME Health 
 
 Kenny “Zulu” Whitmore, 59, has spent the last 28 consecutive years in solitary confinement in Louisiana State Penitentiary at Angola, but a prison warden says he may be released to the general inmate population. 
 
 Whitmore reportedly spends 23 hours a day in a 6-foot by 9-foot cell. “We will get him out,” Warden Burl Cain, warden of the prison, told the Medill Justice Project, a group that investigates potentially wrongful convictions. “We’d rather him out. I need his cell. I’ve got some young people, predators, that need to be in that cell. When I can conclude he’s not going to cause me the blues, then he can come out of the cell.” Whitmore is in prison for second-degree murder. 
 
 According to the Medill Justice Project, Whitmore’s eyesight has deteriorated and he has hypertension. And if he’s similar to other cases of prisoners in solitary confinement, his health and mental health have likely deteriorated in other ways, too. 
 
 “Human beings require two very basic things: social interaction and meaningful activity. By doing things we learn who we are and we learn our worth as a person. The two things solitary confinement does is make people solitary and idle,” says Dr. Terry Kupers, a professor of psychiatry at the Wright Institute in Berkeley California, who has spent over 40 years interviewing thousands of solitary confinement prisoners. 
 
 Though the impact of solitary confinement can differ person to person, there are some basic symptoms that are particularly widespread among inmates. Prisoners of long-term confinement—which Kupers says that’s about three months, though for some effects start to appear much sooner—often experience high anxiety that can cause panic attacks, paranoia and disordered thinking, as well as anger and compulsive actions, like pacing or repeatedly cleaning the cell. Basic cognitive functions are also dulled. “I have prisoners tell me they quit reading, which is one of the only things you can sometimes do,” says Kupers. “I ask why, and they say it’s because they can’t remember what they read three pages before.” 
 
 Prisoners in solitary confinement often develop confusion over when to be alert and when to sleep. In a report, Psychiatric Effects of Solitary Confinement, Stuart Grassian, a former faculty member at the Harvard Medical School and a consultant in criminal cases writes: “[Solitary confinement prisoners] often find themselves incapable of resisting their bed during the day—incapable of resisting the paralyzing effect of their stupor—and yet incapable of any restful sleep at night. The lack of meaningful activity is further compounded by the effect of continual exposure to artificial light and diminished opportunity to experience natural daylight.” 
 
 Grassian tells TIME that without stimulation, people’s brains will move toward stupor and delirium—and often people won’t recover from it. 
 
 Even when prisoners are let out of solitary confinement, Grassian says, they are so overwhelmed by stimulus that they become incapable of tolerating their new environment and have trouble integrating back into the general population. Their brain waves jump and they become highly reactive. “I’ve talked to many of these prisoners who say it’s hellish for them,” says Grassian. “The often end up spending a tremendous amount of time in their cell.” 
 
 Whether Whitmore will be released into the general prison population remains uncertain but the fact that he has been attempting to take legal action against the prison may work in his mental favor, since Grassian says thinkers tend to do better. 
 
 “People that can use their minds tend to do relatively better,” he says. “They are able to maintain a degree of stimulation internally.” 
 
 And that’s all many can rely on. ||||| More 
 
 Albert Woodfox, currently the longest-standing solitary confinement prisoner in the United States, will be released from prison in the coming days. 
 
 Woodfox is the last of the “Angola Three,” convicted on dubious grounds of killing a guard during prison riots at the Louisiana State Penitentiary in Angola, La. in 1972, to be released; Robert King and Herman Wallace, who both served time in solitary confinement while imprisoned, were both released in 2013. 
 
 Sign up for THE BRIEF and more view example 
 
 But Woodfox was held in solitary the longest of the three; for 43 years he has been kept in virtual isolation, his lawyer has said. Although the facts of the case are heavily contested, the adverse health effects of solitary confinement are less so. Amnesty International and the United Nations have both deemed Woodfox’s imprisonment “inhumane.” 
 
 In a July 2014 article, TIME’s Alexandra Sifferlin reported on the impact decades of solitary confinement — such as that imposed on Kenny “Zulu” Whitmore, another Angola inmate in solitary confinement — might have on a patient’s brain: 
 
 Though the impact of solitary confinement can differ person to person, there are some basic symptoms that are particularly widespread among inmates. Prisoners of long-term confinement—which [Dr. Terry Kupers, a professor of psychiatry at the Wright Institute in Berkeley California] says is about three months, though for some effects start to appear much sooner—often experience high anxiety that can cause panic attacks, paranoia and disordered thinking, as well as anger and compulsive actions, like pacing or repeatedly cleaning the cell. Basic cognitive functions are also dulled. “I have prisoners tell me they quit reading, which is one of the only things you can sometimes do,” says Kupers. “I ask why, and they say it’s because they can’t remember what they read three pages before.” Prisoners in solitary confinement often develop confusion over when to be alert and when to sleep. In a report, Psychiatric Effects of Solitary Confinement, Stuart Grassian, a former faculty member at the Harvard Medical School and a consultant in criminal cases writes: “[Solitary confinement prisoners] often find themselves incapable of resisting their bed during the day—incapable of resisting the paralyzing effect of their stupor—and yet incapable of any restful sleep at night. The lack of meaningful activity is further compounded by the effect of continual exposure to artificial light and diminished opportunity to experience natural daylight.” Grassian tells TIME that without stimulation, people’s brains will move toward stupor and delirium—and often people won’t recover from it. 
 
 In many states, solitary confinement takes the form of 23 hours in the cell with no TV, radio, books, music, magazines, or any other distractions. Suicide rates are disproportionately high among those in solitary confinement, and those in solitary confinement who are eventually released are more likely reoffend. 80,000 of the approximately 2.3 million incarcerated people in America are in solitary confinement or some other form of segregated housing. 
 
 Read next: Why Loneliness May Be the Next Big Public-Health Issue 
 
 Listen to the most important stories of the day. ||||| The ordered release of Albert Woodfox after four decades in solitary confinement in Louisiana comes as states are curtailing the ubiquitous use of ‘the box’ as prison punishment. 
 
 The Louisiana State Penitentiary at Angola opens its doors to the public once a year for a prison rodeo, but visitors have never seen an inmate named Albert Woodfox mingling by the stables. 
 
 Instead, Mr. Woodfox, whose conviction for murdering a prison guard during prison unrest in 1972 has twice been overturned, spent most of his four-decade-long sentence at Angola in solitary confinement, alone in a small cell for 23 hours a day. On Monday, a judge cited “the prejudice done onto Mr. Woodfox by spending over forty years in solitary confinement” as one reason he will be released, and why the state will be barred from trying him a third time. 
 
 Amid global scrutiny of a practice that the United Nations has equated in many cases to torture, the Woodfox case is one example of how the United States is taking a hard look at how prison officials use “the box,” as it’s sometimes called, to maintain order and safety behind the razor wire. 
 
 Solitary confinement began in the 1800s as an opportunity for biblical self-reflection, but it has become – especially since the murder of two Marion, Ill., prison guards in 1983 – a go-to punishment for problem inmates, who may end up spending years alone, talking to the walls. 
 
 According to estimates, between 25,000 and 80,000 US inmates are in solitary at any one point. Overuse of solitary, while in many ways understandable, is problematic because recidivism rates – and suicide rates – are higher for solitary inmates. 
 
 And so as America contemplates a broader shift away from harsh punishments like the death penalty and shows renewed interest in reducing the cost burdens of prisons, states from Maine to California are starting to at times dramatically limit the use of isolation. 
 
 “Solitary confinement is something that ought to be used as a last resort, because I don’t think it promotes mental health, so you’re not creating better citizens [upon release],” says Paul Robinson, an expert on criminal sentencing at the University of Pennsylvania Law School in Philadelphia. But at the same time, he says, “sometimes there are very good reasons [for using solitary] because for some people, solitary confinement is the only responsible way to incarcerate them.” 
 
 Calls for reform began as early as 2009, but have picked up pace as legislators and prison officials confront the ethics and expenses of creating large supermax prisons that rely on loneliness and despair to rehabilitate hard cases. 
 
 In the past few years, Maine has cut its solitary population by half, in part by reducing the average stay from three months to two weeks. In 2013, then-Gov. Pat Quinn of Illinois closed the Tamms Correctional Center, which had only solitary units, largely because of its annual $26 million price tag. New York State no longer allows prison officials to send anyone who is pregnant or under 18 to solitary cells, and moves are afoot to eliminate solitary for anyone under 21 at New York City’s Rikers Island. In South Carolina, where some prisoners have spent years alone for breaking prison rules, the maximum time in solitary has been reduced to 60 days, even for numerous, but related, infractions. 
 
 And last year, California complied with a federal judge's order and began removing an estimated 2,500 mentally ill inmates from stark solitary confinement cells to less punitive isolation units. The new policy came after a series of inmate hunger-strike protests against solitary confinement at the state's notorious Pelican Bay State Prison. 
 
 Although hard statistics are difficult to tease out of state prison reports, there is evidence that such reforms work. When Mississippi dramatically reduced the number of solitary prisoners in Unit 32, its supermax facility, after a series of violent incidents in 2007, skeptics feared violence would increase. But replacing solitary with better facilities, including a new basketball court, resulted in far less violence. 
 
 Prison wardens, when polled in the early 2000s, said that using the box was crucial to “increasing ... safety, order, and control throughout prison systems and incapacitating violent or disruptive inmates,” according to a study by Daniel Mears, a Florida State University criminology professor. 
 
 Yet Christopher Epps, the former Mississippi prison chief who oversaw reforms at Unit 32, has summarized its use another way: While prison wardens start out isolating prisoners who scare them, they eventually start using it for inmates they’re “mad at,” as he was quoted in a 2012 New York Times article. 
 
 Professor Robinson says that a push to eliminate solitary altogether is “silly,” at least until anti-punishment activists are willing to spend some time inside America’s more notorious cellblocks. That, however, doesn’t mean that US prison officials can’t do a better job of making sure that solitary punishment is “proportionate” to the infraction, he says. 
 
 Robinson adds that the large number of mentally ill prisoners in US facilities is putting “prison authorities in a tough spot, because justice takes into account aggravations and mitigations, but dealing with people who are mentally ill distorts [that] system in many bad ways.” 
 
 To be sure, proportionality figured into the case of Woodfox, the Angola prisoner. Long having argued that his harsh punishments were payback for his political activism as a Black Panther leader inside the prison, Woodfox may be released as early as this week. Louisiana’s attorney general, however, has indicated he is filing an appeal. For now, Woodfox remains in isolation, but now has access to a TV. 
 
 “Solitary – in theory, a punishment for the worst of the worst, inmates who pose an immediate threat to others – has become a routine disciplinary tool, used in ways for which it was never intended,” wrote Emily Bazelon in The New York Times Magazine earlier this year. “The good news is that this is beginning to change ....” ||||| Albert Woodfox, a Louisiana inmate who has been in solitary confinement for more than 40 years, remained incarcerated Tuesday after a federal appeals court, seeking to give the state time to appeal, temporarily blocked a judge’s order that said the “Angola 3” member should be set free. 
 
 Woodfox, now 68, was charged with murdering prison guard Brent Miller in 1972 and convicted twice, but both of those convictions were overturned. State prosecutors are hoping to try him a third time, although the judge barred it Monday, saying he lacks confidence in the state's ability to provide a fair trial. 
 
 The Angola 3 
 
 As inmates at the Louisiana State Penitentiary in Angola, Woodfox -- who was originally convicted of armed robbery -- and Herman Wallace and Robert King had organized a chapter of the Black Panthers and had begun mobilizing other African American inmates against brutal conditions inside the prison. In 1972, Woodfox and Wallace were accused of murdering Miller and placed in solitary confinement. King, convicted in the death of another inmate, was also placed in solitary — and the three were kept there for decades. 
 
 They maintained that they were kept in solitary as payback for their political activities. Dubbed the Angola 3, they became a cause celebre for prison reform advocates. King spent 29 years in solitary confinement before being released in 2001. Wallace was released from prison in 2013, at age 71, and died days later of complications of liver cancer. King discussed his experiences in the documentary "In the Land of the Free." 
 
 43 years in solitary 
 
 Woodfox has spent the last 43 years in solitary confinement, locked down for 23 hours a day. The solitary cells at Angola have been described by Britain's Guardian newspaper as a 9-by-6-foot space with a toilet, a mattress, sheets, a blanket, a pillow and a small bench attached to the wall. "I can make about four steps forward before I touch the door," Wallace told the newspaper in 2012. "If I turn an about-face, I'm going to bump into something. I'm used to it, and that's one of the bad things about it." Exercise consisted of access to a caged concrete yard three times a week, according to the Guardian. 
 
 'No valid conviction holding him in prison' 
 
 On Monday, U.S. District Judge James Brady ordered the unconditional release of Woodfox from state custody and barred a third trial on the 1972 murder charges. Among his findings, Brady wrote, "There is no valid conviction holding him in prison, let alone solitary confinement." Furthermore, he wrote, "there was an abundance of physical evidence available at the crime scene in 1972, but not one piece of physical evidence incriminated Mr. Woodfox." 
 
 Five factors for freedom 
 
 Brady said in his order that at least five factors combine to justify the "extraordinary remedy" that is Woodfox's unconditional release, including Brady's lack of confidence in the state to provide a fair trial, as well as the years Woodfox has spent in solitary confinement. The factors also included Woodfox’s age and poor health and his limited ability to represent a defense at a third trial due to the unavailability of witnesses, Brady wrote. "And finally," he wrote, "the very fact that Mr. Woodfox has already been tried twice and would otherwise face his third trial for a crime that occurred over 40 years ago." 
 
 Judge bars retrial 
 
 Woodfox will not be tried a third time in the prison guard's death, Brady ordered Monday. "This court questions the strength of the evidence keeping Mr. Woodfox incarcerated for the murder of Mr. Miller," he wrote. "Given the nature of our criminal justice system, Mr. Woodfox, at age 68, is facing perhaps another 20 years before a court determines if he was given a fair third trial." 
 
 Reaction to the news 
 
 Amnesty International, which took up the case, cheered Monday's development. 
 
 Steven W. Hawkins, executive director of Amnesty International USA, said in a statement that Woodfox had suffered "from serious health problems caused or made worse by his years of close confinement." 
 
 State prosecutors, on the other hand, are working to keep Woodfox in prison. With Monday’s order, "the court would see fit to set free a twice-convicted murderer," Aaron Sadler, a spokesman for Louisiana Atty. Gen. Buddy Caldwell, told the Associated Press on Monday. "This order arbitrarily sets aside jury decisions and gives a free pass to a murderer based on faulty procedural issues." 
 
 On Tuesday, the U.S. 5th Circuit Court of Appeals issued a stay temporarily blocking part of Brady’s order so the state can put together an appeal. The block is to expire Friday afternoon. 
 
 Follow Ryan Parker on Twitter, Facebook and Instagram. 
 
 UPDATES 
 
 3:21 p.m. June 9: This story has been updated with information on an appeals court's stay. 
 
 The first version of this story was published at 10:27 p.m. June 8.
– The damaging effects of solitary confinement on a prisoner can appear within three months, sometimes sooner. Albert Woodfox has been in solitary confinement for 43 years, though he could be released from Louisiana State Penitentiary as early as Friday. Since 1972, Woodfox has spent 23 hours a day in a tiny cell that can be crossed in just four paces, the Los Angeles Times reports, but how he'll cope on the outside isn't clear. In a piece last year, Time reported prisoners in long-term isolation are subject to panic attacks, paranoia, disordered thinking, anger, and compulsive actions, like incessant pacing or cleaning, while their basic cognitive functions dim. They also have a hard time sleeping at night. "Without stimulation, people's brains will move toward stupor and delirium—and often people won't recover from it," the magazine reported, noting many are "incapable of tolerating their new environment" when eventually released. Already, Woodfox is battling "serious health problems caused or made worse by his years of close confinement," a rep for Amnesty International says. Both Amnesty and the United Nations agree his treatment has been "inhumane," reports Time. As many as 80,000 US inmates may be in solitary confinement at any one time, reports Christian Science Monitor, though some states are working to reduce that number amid higher rates of reoffending and suicide among the isolated. Still, some say solitary confinement serves a purpose. "For some people, solitary confinement is the only responsible way to incarcerate them," says a criminal sentencing expert. However, he adds, "solitary confinement is something that ought to be used as a last resort, because I don't think it promotes mental health, so you're not creating better citizens" upon release. (A lawsuit reveals the horrors of solitary confinement at Colorado's Supermax.)