Brains in context in the neurolaw debate: The examples of free will and “dangerous” brains - Schleim - 2012 - Article

Now, developments in neuroscience and neurotechnology are important topics of debate. It is argued that neuroscience challenges our notions of free will and responsibility and that this threatens societal practices concerning accountability and punishment for one’s deeds. Possible issues are the adjusting of legal doctrines according to neuroscientific findings or improving the practices in forensic settings, such as the assessment of the credibility of testimony. There are some cases in which neurogenetics, and neuroimaging evidence led to mitigated sentences since they showed a tendency towards aggressive behaviour or a mental disorder. Research has shown that providing neuroscientific knowledge or images increases scientific credibility. Some believe that everything will stand or fall depending on answers that will be given with the help of brain research, whereas others argue that these technologies are not yet ready to be practically applied because of methodological and conceptual limitations. In this article two domains that are important in neurolaw are analysed. The first domain is how neuroscience knowledge is understood psychologically in the context of free will and the second domain is the application of neuroscience forensic settings. Neuroscience explanations depend at least partially on social and psychological context knowledge and therefore they elicit scientific challenges. Neuroscience will probably gradually improve the legal context rather than overthrowing social practices.

What does “free will” mean?

Now, developments in neuroscience and neurotechnology are important topics of debate. It is argued that neuroscience challenges our notions of free will and responsibility and that this threatens societal practices concerning accountability and punishment for one’s deeds. Possible issues are the adjusting of legal doctrines according to neuroscientific findings or improving the practices in forensic settings, such as the assessment of the credibility of testimony. There are some cases in which neurogenetics, and neuroimaging evidence led to mitigated sentences since they showed a tendency towards aggressive behaviour or a mental disorder. Research has shown that providing neuroscientific knowledge or images increases scientific credibility. Some believe that everything will stand or fall depending on answers that will be given with the help of brain research, whereas others argue that these technologies are not yet ready to be practically applied because of methodological and conceptual limitations. In this article two domains that are important in neurolaw are analysed. The first domain is how neuroscience knowledge is understood psychologically in the context of free will and the second domain is the application of neuroscience forensic settings. Neuroscience explanations depend at least partially on social and psychological context knowledge and therefore they elicit scientific challenges. Neuroscience will probably gradually improve the legal context rather than overthrowing social practices.

Freud’s idea that the ego is not the master in its own house is already 100 years old, but it has also become popular in neuroscience research. An example is the research conducted by Libet in the 1980s that showcased that the intention to press a button is preceded by a readiness potential that can be recorded from the premotor cortex. This finding, among others, leads to the idea that the causes behind our actions are maybe not conscious. Although the study has been criticized for various reasons, the finding that the readiness potential does not differ between the decision to move or a decision not to move has been reproduced and this is interpreted as evidence against unconscious movement initiation. A more recent study by Soon and colleagues found that ten seconds before the intention becomes conscious, unconscious determinants of the action, either pressing the left or right button, become visible. The important point here is that behavior might be caused by processes of which one does not have control. There are various aspects on which this experiment by Soon can be criticized, for instance, the predictive value was only 60% whereas 50% is chance level, and many participants were excluded after a pre-test and even after the data was collected.

Subjects were told that, at some point when they felt the urge to do so, they were to freely decide between one of two buttons and press it immediately (Soon et al, 2008). However, in the supplementary material the instructions differed, and subjects were told to relax and to press either the left or right button with the index finger of the corresponding hand immediately when they became aware of the urge to do so. In the first instruction it is assumed that there is a decision process but in the second this is not assumed. This shows a conceptual problem of what it exactly means to have the urge to press a button, which is an urge that is not often present in daily life and it undermines the meaning of the kind of decision the subjects had to make, if it was a decision at all.

The second critical point relates to the brain areas from which the predictions were made, the lateral areas in the prefrontal cortex. It could be expected that brain areas that are more often related to unconscious biases were activated, but the contrary was found. The subjects had to assign the time of the conscious intention to perform the action, and this presumes that a psychological process is unconscious and suddenly pops up into consciousness. In this way it is not possible that such a process enters consciousness gradually. Especially because of the high-level control areas, it is neuroscientifically implausible to argue for unconscious determinants that undermine free will.

The compatibilist stance, that is, the idea that determination of actions is compatible with free will, is no solution for the free will problem. If our actions were caused by unconscious processes without control, it would undermine our understanding of being, to some extent, rational agents. It might be possible that, over time, the assessment of the mental capacities of a victim will be complemented or replaced by neuroscience but only if these capacities can be translated into assessable neuroscientific properties. It is the question to what extent neuroscience can add something to the behavioral ascriptions of mental capacity that are used currently. Also, there are various statistical-theoretical considerations such as that findings should be generalizable to the real world, and not only to experimental settings. Furthermore, practical relevance has to be demonstrated, since significance on average will not be sufficient to refute rationality in general. In addition, irrationality should be found in all kinds of situations since not being rational in some situations does not mean that people are irrational at all. People should also look at evidence against the notion that we are irrational actors.

For example, in priming tasks in which a subliminal (unconscious) prime is provided, this should lead to a reduced reaction time if the prime were to be effective, which is also found in a study by Jaskowski (2008). In another study it was found that the more mindful participants are, the less susceptible to unconscious priming they are. This can be interpreted as favoring the idea of having at least some conscious control of our actions.

What is meant by ‘dangerous brain’?

In the debate on forensic implications of neuroscience, researchers often refer to cases where acquired brain damage is related to criminal behavior. The case of Phineas Gage is one of the most famous examples, but various aspects of this case are misinterpreted, leading to over-estimation of the contribution of brain damage on behaviour. Gage lost an amount of brain tissue in the ventromedial prefrontal cortex (VMPFC) after an accident with a tamping iron. It is stated that Gage has become a pseudo-psychopathic, immoral person and that this change was the direct consequence of the accident damaged his VMPFC. Macmillian has found that in the past 150 years the descriptions of the accident and therefore the personality changes have changed a lot. Among others, after the accident Gage was described as clear and rational but when recovered from the shock, many people wanted to stick their fingers into the wound to see whether it was possible to touch the other finger inside the skull. This is a relevant detail because Gage also had severe infections afterwards. Furthermore, there are only a few statements in the report of Harlow (his doctor) that provide evidence for personality changes. Other people who saw Gage in his first year after the accident did not mention any personality issues. Only in the report published by Harlow 20 years after the accident and eight years after Gage’s death because of epileptic fits, personality issues were reported. It can thus be concluded that the evidence for personality change is scarce and abstract, and that it does not refer to criminal behavior. In addition, associations with brain damage neglects trauma effects or damage due to infection of epileptic fits.

More recent cases that are often referred to are those of EVR and JZ who had both suffered from a brain tumor which was surgically removed. JZ fulfilled five of the core DSM 3 criteria of an antisocial personality disorder (ASPD) such as lack of consistent work behavior and failures in planning. Although these problems lead to impaired functioning, this is also not real criminal behavior. Moreover, the criteria for sociopathic disorder and ASPD changed over time which means that when criteria change, the opinions about whether these patients were antisocial can change as well.

Another case that is often mentioned is that of a 40-year-old man who started collecting child pornography and molesting his stepdaughter. He could choose between undergoing a treatment or go to jail. He chose the treatment but was expelled from it and had to go into prison. The evening before, he increasingly experienced neurological problems and after a MRI scan huge tumors were found in his right orbitofrontal cortex. After resection of the tumor, the man successfully followed a treatment program. However, after a few months he started collecting pornographic materials again, and his headache returned. Regrowth of the tumor was discovered and after removing this, his behavior improved again. It is thus easy to conclude that the brain tumor caused his pedophilia, but there are strong reasons to doubt this. The reason for this is that this person’s problem was much more general than only child pornography and although this might be interpreted as limited capacity of self-control, there is also evidence that he did have some self-control. For instance, he was able to hide the pornographic materials and he was able to go to the hospital on his own. He was thus aware that his actions were wrong and he was able, to some degree, to resist his urges. Therefore, he was minimally rational although his neurological problem might have been an aggravating factor. It becomes clear that each case has to be analyzed individually and thoroughly. Also, since parts of his VMPFC had been removed, antisocial behavior could have been expected but this was not the case.

What do real-life cases show us?

The following two cases provide evidence against a direct link between damage to the VMPFC and criminality. A man who had fallen into a spiked iron gate at age 20 did not have problems until 60 years later. During the accident, large parts of his VMPFC were damaged. After the accident, the man became dependent on others and was incapable of planning and fulfilling his responsibilities. However, he was also cheerful and did not experience difficulties in controlling his emotions. He had a very caring environment and did not need psychiatric services. Another example is that of a 33-year-old man who had previously shown pathologic aggressive and violent behavior. After a failed suicide whereby his VMPFC was damaged, he became docile, indifferent to his situation, and inappropriately cheerful.

Associations between VMPFC damage and antisocial or criminal behavior are frequently present in the literature as shown by the described cases. However, a meta-analysis showed that the problems after brain lesions do not have to be of a criminal nature. The course of life is also dependent on social support. The VMPFC cannot be seen as an area where morality or appropriate behavior is localized. According to the article, the mentioned cases received too much attention and contextual features are often neglected. Also, meta analyses show that criminals do not share neural conditions at all. We can doubt that complex behaviors such as in ASPD (antisocial personality disorder) can be localized in the brain because it is such a general category of behaviors. ASPD can be diagnosed in individuals who do not share any symptoms as 99 different combinations of symptoms can be made.