Wednesday, October 5, 2016

The Predictive Power of Neuroimaging

By Ethan Morris

This post was written as part of a class assignment from students who took a neuroethics course with Dr. Rommelfanger in Paris of Summer 2016. 

Ethan Morris is an undergraduate senior at Emory University, majoring in Neuroscience and Behavioral Biology with a minor in History. Ethan is a member of the Dilks Lab at Emory and is a legislator on the Emory University Student Government Association. Ethan is from Denver, Colorado and loves to ski.   

Background and Current Research

Neuroscience is a rapidly burgeoning field that is increasingly facing complex issues as scientists learn more about the human brain and by extension, about personal identity. One technology that has gained attention in the last two decades is brain imaging, a technique that uses various tools to evaluate the brain’s functional response to the world. Some of the more commonly used brain imaging devices are functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), both of which measure blood flow (albeit by different mechanisms) through the brain. These blood flow results show which areas of the brain are metabolically active, and are thus activated by the task at hand. Using these devices, researchers can determine the activity of certain brain regions associated with certain types of sensory and perceptual processing, as well as cognitive function.

While used in clinical settings for neurological and psychiatric diagnoses, neuroimaging is also applied in a variety of research contexts to learn about the neural correlates of human behavior. One study examined fMRI activation levels in the amygdala, one of the brain’s centers for processing salient stimuli and emotion. The researchers found that white individuals displayed greater amygdala activation for unfamiliar black faces than familiar white faces, and moreover, there was a positive correlation between amygdala activation and unconscious racial bias (Phelps et al., 2000). Importantly, imaging cannot read human minds, but it is significant that brain-imaging patterns are being used currently to make important inferences about unconscious thoughts, even if they are not manifested behaviorally.

Image courtesy of WikiCommons
In another study, researchers found that prisoners with higher levels of psychopathy were more likely to have fewer connections between the parietal cortex and the anterior cingulate cortex (Philippi, 2015). The implication of this study is that it may be possible to identify psychopaths and potentially predict who is more likely to be rearrested based on brain connectivity. In a juvenile study, researchers used fMRI and found that certain patterns of functional connectivity between the premotor and prefrontal cortices were predictive of future impulsivity (Shannon et al., 2011). These studies demonstrate the current capability of neuroimaging to assess unconscious biases and perhaps predict future behavior, such as recidivism or impulsivity.

Ethical Considerations 

In order to inform policy, there are important ethical considerations regarding both current neuroimaging knowledge and future applications of this technology. Provided these studies are replicated and verified, neuroimaging might be used to infer unconscious attitudes and predict future behavior. Is it ethical to image the brains of prisoners to determine their likelihood of ending up back in jail? Even if certain images are correlated with rates of recidivism, it is still difficult to accurately predict future human behavior using neuroimaging. Brain images are transient portraits, which limits researchers’ abilities to extrapolate moment-to-moment brain states to label the brain and person (Fuchs, 2006). Additionally, brain imaging is susceptible to misinterpretation by researchers who do not fully understand the appropriate conclusions one can make with imaging. This could lead to dangerous conclusions from brain images about the entire identity of a person without meaningful evidence. Another limit of neuroimaging is the lack of causational data (e.g. brain activity X causing behavior Y). With neuroimaging, researchers are often only able to correlate brain images with certain functions or mental states (Miller, 2008). Knowing these limits, it does not seem possible right now to definitively predict future behavior. However, placed in eager hands, brain imaging could be used to predict recidivism, which may inevitably result in false positive results, placing prisoners at the mercy of their brain’s activity, perhaps without justification.

On a fundamental level, is it fair to judge a person for what their brain looks like? In the case of the correctional system, this may undermine its purported goal of assisting “offenders in becoming law-abiding citizens” (US Federal Bureau of Prisons). For example, consider a prisoner who appears completely rehabilitated, but whose brain images show a prefrontal cortex deficit associated with impulsivity and future recidivism. Would society deem it fair to place him under stricter parole than it would have without brain imaging? This can be reduced to whether brain images should be accounted for, even if what is observed does not manifest in behavior.

Another ethical concern is society’s widespread belief in free will. It is a commonplace belief that, as a human, one has an intrinsic ability to choose what one will do, no matter the environment or genetics that may predispose certain behaviors. Would society think it is ethical to judge a person for their neurobiology? Some may argue that it would contradict the belief that released prisoners have the ability to avoid committing another crime. Humans value the right to autonomy, or self-determination, so should parole boards meddle in the autonomy of others based on imaging conclusions about their risk for future behavior?

Image courtesy of Pixabay
This ethical issue is particularly pertinent for juvenile offenders. To what degree should the justice system implement brain imaging to predict recidivism or impulsivity if it has been shown the human brain does not finish developing until the mid-20s (Giedd, 1999)? Because studies have shown that adolescents gain white matter and lose impulsivity with age, it may not be ethical to use brain images to predict behavior if they are no longer accurate within a couple years (Casey, 2005). One final ethical consideration of neuroimaging is privacy. There is potential that in the future, scientists may be able to use brain imaging as an identity scanner. Scientists might be able to “’read personality features, psychiatric history, truthfulness and hidden deviations from a brain scan” (Fuchs, 2006). As Fuchs mentions, this application could get misappropriated quickly and invasively, as private companies and lawyers may misuse brain imaging to label and potentially defame people, all based on brain scans. The issue of consent also arises—how does someone lying in an fMRI scanner know what the person behind the operating computer is looking at?

Policy Recommendations 

With these technological limitations and ethical issues in mind, there are multiple policy recommendations to prevent violation of privacy and consent, false positives, and dangerous conclusions. On the issue of consent and privacy, the Department of Health and Human Services (HHS) should ensure that institutional review boards (IRBs) enforce limits on what researchers can image. These limitations should extend into the courtroom, where fMRI could be applied as superior or overriding evidence without sufficient basis. Researchers should only be able to image regions of the brain needed for their research and should be prohibited from using unrelated information that may be outside of participants’ consent/privacy and their research’s purview. Participant consent forms should contain explicit explanation regarding the technology, capabilities, and targeted brain areas so all parties are informed.

Whether through the US Security and Exchanges Commission (SEC) or the US Food and Drug Administration (FDA), the private sector should not have access to brain imaging in its current state. Due to the realistic limitations of imaging, false positives and unwarranted speculation about personal identity are likely to result from unregulated use of brain imaging and should be prevented to avoid personal judgments that may not have any tangible basis. Additionally, the possibility for this research to negatively influence public understanding of neuroscience dictates that powerful tools such as neuroimaging should not be introduced outside of research settings until the tool’s capabilities and limitations are fully understood.

The US Department of Justice should outlaw use of brain imaging in youth detention centers to avoid rampant false positive predictions, given the current knowledge about how decision-making improves with brain development. In addition, parole boards should not be allowed to use imaging to determine the chances an adult prisoner will commit another crime. If the justice system collectively decides brain images are paramount to demonstrated human behavior, brain imaging could theoretically antiquate and undermine the justice system’s efforts to improve actual human behavior. This must not be the case—the ultimate goal of prison should be to change behavior, not neurobiology.

 In the realm of research, review boards must vigorously review brain-imaging studies. It is simply too dangerous to publish conjectural conclusions about brain imaging because of the distinct possibility for misappropriation and for sensationalist media stories. The caveats and limitations of brain imaging (e.g. the lack of causational data) must be emphasized at the front line—the researchers—in an attempt to prevent false positives, and to prevent non-researchers from misapplying neuroimaging. Researchers and journals must be vigilant about disseminating correct results with appropriately stipulated interpretations to prevent misreporting. Furthermore, researchers must be held accountable by IRBs for their studies in an effort to prevent publications of flimsy associative data that may be misinterpreted. Additionally, there should be restrictions on researchers’ conflicts of interest regarding neuroimaging; for example, the US Department of Justice should be barred from funding neuroimaging in an effort to predict post-prison behavior until the technology proves reliable and causational.

Neuroimaging should continue to be used appropriately and realistically will be used in both research and clinical contexts going forward. Because of this, the HHS should implement a public education strategy to inform media members, lawyers and parole board members, as well as the public of the capabilities and limitations of brain imaging to prevent avoidable ethical problems and public fear of neuroimaging.

References 

Casey, B.J., A. Galvan, T.A. Hare. 2005. Changes in cerebral functional organization during cognitive development. Current Opinion in Neurobiology, 15: 239-244.

Federal Bureau of Prisons. About our agency: A foundation built on solid ground. Available here.

Fuchs, T. 2006. Ethical issues in neuroscience. Current Opinion in Psychiatry, 19: 600-607.

Giedd, J.N., J. Blumenthal, N.O. Jeffries, et al. 1999. Brain development during childhood and adolescence: a longitudinal MRI study. Nature Neuroscience, 2(10): 861-863.

Miller, G. 2008. Growing pains for fMRI. Science, 320(5882): 1412-1414.

Phelps, E.A., K.J. O’Connor, W.A. Cunningham, et al. 2000. Performance on indirect measures of race evaluation predicts amygdala activation. Journal of Cognitive Neuroscience, 12(5): 729-738. 

Philippi, C.L., M.S. Pujara, J.C. Motzkin, J. Newman, K.A. Kiehl, M. Koenigs. 2015. Altered resting-state functional connectivity in cortical networks in psychopathy. The Journal of Neuroscience, 35(15): 6068-6078.

Racine, E., O. Bar-Ilan, J. Illes. 2005. fMRI in the public eye. Nature Reviews Neuroscience, 6(2): 159-164. Shannon, B.J., M.E. Raichle, A.Z. Snyder, et al. 2011.

Premotor functional connectivity predicts impulsivity in juvenile offenders. PNAS, 108(27): 11241-11245. University of Washington. Brain imaging. Available here.

Want to cite this post?

Morris, E. (2016). The Predictive Power of Neuroimaging. The Neuroethics Blog. Retrieved on , from http://www.theneuroethicsblog.com/2016/10/the-predictive-power-of-neuroimaging.html

1 comment:

Becky G said...

Eve Maram has a book called Psychopathy Within, she explains that this is a character trait, and that with her forensic and psychology background to have a psychopath as a family member really made her look at this differently. It's a very good read on a very intense situation.