لخّصلي

Abstract
Post-Traumatic Stress Disorder (PTSD) is a complex psychiatric condition, the effects of which can be seriously debilitating. As it originates from a specific traumatic event, it often impacts soldiers and victims of violent crime. It is currently one of the most frequently litigated mental diseases. Neuroscience is slowly discovering the neural bases of PTSD and other psychiatric ailments and is building tests to distinguish actual patients from non-suffering individuals. We examine the current state of neuroscientific research on PTSD and its biomarkers, focusing on a recent experiment by Apostolos Georgopoulos and coworkers. Then we analyze the legal consequences of these scientific advances, both in civil and criminal law, from a comparative perspective. Neuro-technology is likely to provide courts with a new kind of evidence, which will not replace but add to older behavioral evidence. Furthermore, it will weaken the so far standing distinction between physical and emotional harm. However, even extremely sensitive tests (> 95%) can have insufficient accuracy if the prevalence of a condition in the tested population is low. Therefore, the law ought to take into account the prevalence of PTSD and other psychiatric conditions when the decision whether to admit neuro-evidence in courts or not is made.

Introduction
Post-Traumatic Stress Disorder (PTSD) is defined by four main symptoms: (1) re-experiencing of painful memories, (2) effortful avoidance of trauma cues, (3) emotional numbing, and (4) hyper-arousal. The disorder arises from exposure to one or more potentially life-threatening events. Much of the neurobiological correlates of PTSD still remain hypothetical or undetermined today. This makes the legal assessment of this disorder complex.
The use of brain imaging techniques has recently allowed researchers to uncover some of the neural networks involved in PTSD. Two of the most recurrent findings in PTSD patients are decreased medial prefrontal cortex (MPFC) and increased amygdala activation.
In 2010, however, the team led by A. Georgopoulos at the University of Minnesota used MagnetoEncephaloGraphy (MEG) to directly measure the magnetic fields produced by electrical activity in the brain of PTSD-affected war veterans and healthy controls. They examined the subjects in a task-free condition, seeking to spot differences in cortical communication in their steady-state brains. According to the team, steady-state MEG allows classification of PTSD patients and healthy subjects with an accuracy of about 90% through a recurrent MEG pattern in the right temporal lobe. The intensity of this signal reliably correlates with the severity of PTSD symptoms in patients, so that severity assessment is possible.
Comparing Italian, US and English legal systems, this paper analyzes how improvements in neuroscientific research regarding PTSD would be extremely relevant to the law, with a special focus on tort law. First, improving PTSD assessment methods for victims of crimes (e.g. child abuse2 or sexual assault) would be important to determine civil compensation. Furthermore, neuroscientific techniques could be used to determine compensatory damages in tort law. This could lead to a re-evaluation of the distinction between physical and emotional harm. Emotional harm has been defined as including “distress […] anxiety, diminished enjoyment, loss of autonomy, and similar intangible harms”.

Section snippets
The origin of PTSD: a brief history
PTSD was a source of controversy long before its first appearance in the third edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-III) in 1980.
The alleged presence of the disorder has been reported in past centuries. The British Journal of Psychiatry, for instance, described how the Diary of Samuel Pepys3
The state of the art
Neuroimaging is mainly composed of three different techniques: functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), and Single Photon Emission Computed Tomography (SPECT) (Francati, Vermetten, & Bremner, 2007). All of these techniques measure signals that have to do with variations in the regional Cerebral Blood Flow (rCBF). When a region of the brain is more active than a baseline, it consumes more energy and recruits more blood. Even though the correlation is not
PTSD in court
The assessment of PTSD in court has great importance both in criminal and civil trials. In the former case, it might lead to the solution of a case, because the presence of PTSD can be considered as evidence that a criminal act (the traumatic event, such as a rape) has indeed occurred.6
In civil cases the presence of a psychological trauma is crucial in order to
Neuroscientific evidence of PTSD in civil and tort law
The chances offered by science to assess the presence of a disease have led to the increased use of experts in the courts of law. The British Psychological Society defines an expert as “a person who through special training, study or experience, is able to furnish the Court, tribunal, or oral hearing with scientific or technical information which is likely to be outside the experience and knowledge of a judge, magistrate, or jury.”23
Conclusions
Starting from the analysis of the recent Georgopoulos and colleagues' experiments, targeted to find a biomarker for Post Traumatic Stress Disorder, we have explored the relationships between neuroscience, PTSD, and law. Our main claims have been the following:

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In the future, neuroscience might be able to provide courts with new tools to diagnose PTSD and to assess the presence of chronic pain, even though neuro-technologies are unlikely to be applicable to the general population because of low

  
  

  
  

Acknowledgments
We thank Jens Schwarzbach for his very helpful comments on the early draft of the paper, and for the discussion at the CIMEC—Center for Mind/Brain Sciences in Rovereto, Trento. Thanks to Marina Boccardi and Chris Domenick for their final suggestions. We are grateful to the University of Pavia and the Fondazione Maugeri (Italy) for conferring us the 2nd prize for the presentation of an earlier draft of this article at the Young Scholar Symposium 2011 (Pavia, June 10th 2011).