The role of frontal EEG asymmetry in post-traumatic stress disorder.

Frontal alpha asymmetry, a biomarker derived from electroencephalography (EEG) recordings, has often been associated with psychological adjustment, with more left-sided frontal activity predicting approach motivation and lower levels of depression and anxiety. This suggests high relevance to post-traumatic stress disorder (PTSD), a disorder comprising anxiety and dysphoria symptoms. We review this relationship and show that frontal asymmetry can be plausibly linked to neuropsychological abnormalities seen in PTSD. However, surprisingly few studies (k = 8) have directly addressed frontal asymmetry in PTSD, mostly reporting that trait frontal asymmetry has little (if any) predictive value. Meanwhile, preliminary evidence suggest that state-dependent asymmetry during trauma-relevant stimulation distinguishes PTSD patients from resilient individuals. Thus, exploring links between provocation-induced EEG asymmetry and PTSD appears particularly promising. Additionally, we recommend more fine-grained analyses into PTSD symptom clusters in relation to frontal asymmetry. Finally, we highlight hypotheses that may guide future research and help to fully apprehend the practical and theoretical relevance of this biological marker.

[Neuroscience in the courtroom? We first need a protocol]. / Neurobewijs in de rechtszaal? Eerst een protocol.

Neuroscientific evidence is prominently present in courts of law and may come in many forms. For example, it may consist of neuroradiological and/or neuropsychological results that are brought to courts to make the point that the claimant is suffering from dementia, ruling out his legal capacity to sign contracts. Neuroscientific evidence has an aura of solidity and objectivity and has been found to have a strong influence on the sentencing decisions of professional judges. In this article, we address one often overlooked issue, namely the biasability of neuroscientific evidence. We argue that neuroscientific evidence is sensitive to pathology bias, allegiance effects, and malingering (by claimants and defendants). In our view, neuroscientific evidence requires a protocol protecting expert witnesses against the biasing effects that are often inherent to the legal context. Such a protocol could, for example, emphasize blinding of procedures.

[When the suspect hears voices: feigned imperative hallucinations]. / Een verdachte die stemmen hoort: geveinsde bevelshallucinaties.

BACKGROUND: On occasion a suspect will feign psychotic symptoms such as hallucinations in order to trivialize their criminal responsibility. If doctors exercise only their clinical judgement, however, every now and then they will fail to identify a malingerer. CASE DESCRIPTION: A 38-year-old male was remanded in custody. He was accused of having murdered 2 family members. He claimed that he had committed the murders as a result of hearing imperative hallucinations. We conducted a structured interview and specially designed tests to examine the plausibility of this claim. All our instruments pointed to the man having feigned his imperative hallucinations. When confronted with this, he confirmed that he had simulated his hallucinations. CONCLUSION: Feigned hallucinations in a forensic setting can be detected using validated tests.

Extracting concealed information from groups.

Lie detection procedures are typically aimed at determining guilt or innocence of a single suspect. Serious security threats, however, often involve groups, such as terrorist networks or criminal organizations. In this report, we describe a variant of the skin conductance-based Concealed Information Test (CIT) that allows for the extraction of critical information from such groups. Twelve participants were given information about an upcoming (mock) terrorist attack, with specific instructions not to reveal this information to anyone. Next, each subject was subjected to a CIT, with questions pertaining to the details of the attack. Results showed that for every question, the average skin conductance response to the correct answer option differed significantly (p < 0.05) from those to all other options. These results show that the information about the upcoming attack could be extracted from the group of terror suspects as a whole.

Sex offender management using the polygraph: a critical review.

Reducing recidivism is a central goal in the treatment of sex offenders. In Europe, there is an increased interest in using the polygraph ("lie detector") as a tool in the treatment and risk assessment of convicted sex offenders. This interest originated from optimistic reports by American clinicians who argued that polygraph testing in the treatment of sex offenders is akin to urine analysis in the treatment of drug addiction. In this article, we critically examine the validity and utility of post-conviction sex offender polygraph testing. Our review shows that the available evidence for the claims about the clinical potential of polygraph tests is weak, if not absent. We conclude that portraying post-conviction polygraph testing as analogous to urine analysis is inaccurate, misleading, and ultimately, risky.

Heritability of self-reported phobic fear.

Twin studies on fear and phobia suggest moderate genetic effects. However, results are inconclusive regarding the presence of dominant genetic effects and sex differences. Using an extended twin design, including male and female twins (n = 5,465) and their siblings (n = 1,624), we examined the genetic and environmental influences on blood-injury, social, and agoraphobic fear and investigated their interaction with sex and age. Data of spouses (n = 708) of twins were used to evaluate assortative mating for the three fear dimensions. Results showed that there was no assortative mating for blood-injury, social and agoraphobic fear. Resemblance between biological relatives could be explained by additive and non-additive genetic effects for blood-injury and agoraphobic fear in all participants, and social fear in participants aged 14-25 years. For social fear in participants aged 26-65 only additive genetic effects were detected. Broad-sense heritability estimates ranged from 36 to 51% and were similar for men and women.

The P300 is sensitive to concealed face recognition.

In two experiments, we investigated whether a P300 based Concealed Information Test (CIT) can be used to detect concealed face recognition. The results show that detection of concealed face recognition is highly successful when stimuli depict persons who are personally highly familiar, and instructions to conceal recognition are given. When pictures depict recognized, but personally less familiar faces, and no specific instructions to conceal recognition are given, detection is unsuccessful. These findings indicate that pictures of faces can be used in a P300 based CIT, and that mere recognition is not sufficient for successful detection of concealed information.

Combining skin conductance and forced choice in the detection of concealed information.

An advantage of the concealed information polygraph test (CIT) is that its false positive rate is determined on statistical grounds, and can be set a priori at arbitrary low levels (i.e., few innocents declared guilty). This criterion, however, inevitably leads to a loss of sensitivity (i.e., more guilty suspects declared innocent). We explored whether the sensitivity of a CIT procedure could be increased by adding an independent measure that is based on an entirely different psychological mechanism. In two experiments, we explored whether the accuracy of a CIT procedure could be increased by adding Symptom Validity Testing (SVT), a relatively simple, forced-choice, self-report procedure that has previously been used to detect malingering in various contexts. Results of a feigned amnesia experiment but not from a mock crime experiment showed that a combination measure of both tests yielded better detection than either test alone.