Day after day, year after year, imagine having no space to call your own, no choice over who to be with, what to eat, or where to go. There is threat and suspicion everywhere. Love or even a gentle human touch can be difficult to find. You are separated from family and friends.
If they are to cope, then prisoners confined to this kind of environment have no option but to change and adapt. This is especially true for those facing long-term sentences – in England and Wales, around 43% of sentences now last more than four years.
In a report on the psychological impact of imprisonment for the US government, the social psychologist Craig Haney (who collaborated with Philip Zimbardo on the infamous Stanford Prison Experiment) was frank: “few people are completely unchanged or unscathed by the [prison] experience”.
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Based on their interviews with hundreds of prisoners, researchers at the Institute of Criminology at the University of Cambridge went further, stating that long-term imprisonment “changes people to the core”. Or in the stark words of a long-term inmate interviewed for research published in the 1980s, after years in prison “you ain’t the same”.
In the field of personality psychology, it used to be believed that our personalities remain largely fixed in adulthood. But recent research has found that, in fact, despite relative stability our habits of thought, behaviour and emotion do change in significant and consequential ways – especially in response to the different roles that we adopt as we go through life. It is almost inevitable then that time spent as a prisoner, in a highly structured yet socially threatening environment, is bound to lead to significant personality changes.
Particularly for anyone concerned about prisoner welfare and how to rehabilitate former convicts, the worry is that these personality changes, while they may help the prisoner survive their jail time, are counter-productive for their lives upon release.
Key features of the prison environment that are likely to lead to personality change include the chronic loss of free choice, lack of privacy, daily stigma, frequent fear, need to wear a constant mask of invulnerability and emotional flatness (to avoid exploitation by others), and the requirement, day after day, to follow externally imposed stringent rules and routines.
There is surprisingly little research on how these chronic features of the environment might change prisoners’ personalities in terms of the “Big Five” model of personality that dominates most modern research on the general, non-prison population (based around the key traits like extroversion and conscientiousness).
Nonetheless, there is widespread recognition among psychologists and criminologists that prisoners adapt to their environment, which they call “prisonisation”. This contributes towards a kind of “post-incarceration syndrome” when they are released.
Consider the findings from 'in-depth interviews with 25 former ‘lifers’ (including two women) in Boston, who had served an average of 19 years in jail. Analysing their narratives, psychologist Marieke Liema and criminologist Maarten Kunst found that the former prisoners had developed “institutionalised personality traits”, including “distrusting others, difficulty engaging in relationships [and] hampered decision-making”.
If you are hardened in the beginning then you become even harder, you become even colder
One 42-year-old male former prisoner said: “I do [still] kind of act like I'm still in prison, and I mean you [are] not a light switch or a water faucet. You can't just turn something off. When you've done something for a certain amount of time… it becomes a part of you.”
The personality change that most dominated their accounts was an inability to trust others – a kind of perpetual paranoia. “You cannot trust anybody in the joint,” said another of the interviewees, a man now aged 52. “I do have an issue with trust, I just do not trust anybody.”
Interviews with hundreds of UK prisoners undertaken by Susie Hulley and her colleagues at the Institute of Criminology painted a similar picture. “Many… told us that they had undergone significant and sometimes wholesale personal transformations,” the researchers wrote in 2015.
The prisoners described a process of “emotional numbing”. “It does harden you. It does make you a bit more distant,” one said, explaining how people in jail deliberately conceal and suppress their emotions. “It is who you become, and if you are hardened in the beginning then you become even harder, you become even colder, you become more detached.” Another prisoner stated: “It’s... I, kind of, don’t have feelings for people” any more.
Released prisoners may be less capable of living a lawful life than they were prior to their imprisonment
In terms of the Big Five personality traits, one could characterise this as a form of extreme low neuroticism (or high emotional stability or flatness), combined with low extraversion and low agreeability – in other words, not an ideal personality shift for the return to the outside world.
That is certainly the concern of Hulley and her colleagues. “As the long-term prisoner becomes ‘adapted’ – in the true sense of the term – to the imperatives of a sustained period of confinement, he or she becomes more emotionally detached, more self-isolating, more socially withdrawn, and perhaps less well suited to life after release,” they warned.
The interview-based studies so far involved long-term prisoners incarcerated for many years. But an exploratory paper published in February 2018 used neuropsychological tests to show that even a short stay in prison had an impact on personality. The researchers led by Jesse Meijers at Vrije Universiteit Amsterdam tested 37 prisoners twice, three months apart. At the second test, they showed increased impulsivity and poorer attentional control. These kinds of cognitive changes could indicate that their conscientiousness – a trait associated with self-discipline, orderliness and ambition – has deteriorated.
The researchers think the changes they observed are likely due to the impoverished environment of the prison, including the lack of cognitive challenges and lost autonomy. “This is a significant and societally relevant finding,” they concluded, “as released prisoners may be less capable of living a lawful life than they were prior to their imprisonment”.
It can help to be conscientious to stay out of trouble
However, other findings offer some glimmers of hope. For another recent paper – one of the few to apply the Big Five model to prisoner personality change – researchers compared the personality profiles of maximum security prisoners in Sweden with various control groups, including college students and prison guards. They found that while the prisoners scored lower on extroversion, openness, and agreeableness, as you might expect, they actually scored higher on conscientiousness, especially the 'sub-traits’ of orderliness and self-discipline.
The researchers, led by Kristianstad University’s Johanna Masche-No, don’t believe this was due to a social desirability effect – that the prisoners were trying to make a good impression on the team asking them questions – because the results were confidential and the prisoners described themselves in unflattering terms on other traits like agreeability.
Instead, the researchers think their findings may reflect a form of positive personality adjustment to the prison situation: “The environment in a prison is very strict with respect to both regulations and norms, and private space is limited,” they concluded. “Such an environment places demands on inmates to acquire order to avoid both formal punishment and negative acts from co-inmates.”
In other words, it can help to be conscientious to stay out of trouble.
Although these findings from Sweden seem to contradict the Dutch research, it’s worth noting that while the Dutch prisoners became more impulsive and less attentive, they also showed improvements in their spatial planning abilities, which could be seen as related to orderliness (Meijers and his colleagues did not read too much into this improvement because they said it could just have been that the prisoners scored higher on the test the second time round because they’d had more practice at it). Another possibility is that the high conscientiousness seen in the Swedish prisoners is specific to their country’s prison system, where there is a greater emphasis on treatment and rehabilitation than in many other countries.
A common perception… is that criminals are bad guys who lack prosocial motivation
Also hopeful, and somewhat in line with the Swedish findings, two recent studies involved prisoners playing financial games that are often used to study cooperation, risk-taking and punishment (one of the games is unrelatedly called The Prisoner’s Dilemma). These showed that prisoners engaged in normal or even heightened levels of cooperation.
The findings have implications for debates about the reintegration of criminals into society, says
Sigbjørn Birkeland at the NHH Norwegian School of Economics, who conducted one of these studies with colleagues. “A common perception… is that criminals are bad guys who lack prosocial motivation and this perception may potentially be used to justify harsh sentencing of criminals,” they wrote. Their results show, they said, that criminals can be just as “equally pro-socially motivated as the general population.”
As awareness grows that personality is malleable, hopefully this will lead to greater efforts to consider how the prison environment can shape an inmate’s character. This clearly could affect their return to society.
There is currently a dearth of existing research with this explicit aim. For now, the evidence we have suggests that prison life leads to personality changes that are likely to hamper a person’s rehabilitation and reintegration. To one extent that may be inevitable, given the loss of privacy and freedom.
But that said, the research findings regarding prisoner conscientiousness and cooperation show all hope is not lost, and they highlight potential targets for rehabilitation programmes.
These are not merely abstract issues of concern to scholars: they have profound implications for how we as a society wish to deal with those who break our laws. The current evidence suggests that the longer and harsher the prison sentence – in terms of less freedom, choice and opportunity for safe, meaningful relationships – the more likely that prisoners’ personalities will be changed in ways that make their reintegration difficult and that increase their risk for re-offending.
Ultimately, society may be confronted with a choice. We can punish offenders more severely and risk changing them for the worse, or we can design sentencing rules and prisons in a way that helps offenders rehabilitate and change for the better.
Dr Christian Jarrett edits the British Psychological Society's Research Digest blog. His next book, Personology, will be published in 2019.
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