No abstract

When individuals who commit a crime are questioned, they often show involuntary physiological responses to remembered details of that crime. This phenomenon is the basis for the concealed information test, in which rarely occurring crime-related details are embedded in a series of more frequently occurring crime-irrelevant items while respiratory, cardiovascular, and electrodermal responses are recorded. Two experiments were completed to investigate the feasibility of using facial skin surface temperature (SST) measures recorded using high definition thermographic images as the physiological measure during a concealed information test. Participants were randomly assigned to nondeceptive or deceptive groups. Deceptive participants completed a mock-crime paradigm. A focal plane array thermal imaging radiometer was used to monitor SST while crime-relevant and crime-irrelevant items were verbally presented to each participant. During both experiments, there were significant facial SST differences between deceptive and nondeceptive participants early in the analysis interval. In the second experiment, hemifacial (i.e., "half-face" divided along the longitudinal axis) effects were combined with the bilateral responses to correctly classify 91.7% of participants. These results suggest that thermal image analysis can be effective in discriminating deceptive and nondeceptive individuals during a concealed information test.

In a preliminary attempt to determine the generalizability of data from laboratory mock-crime studies, the authors examined the similarities and differences among the cardiovascular, electrodermal, and respiration responses of deceptive and nondeceptive individuals elicited to crime-relevant and crime-irrelevant questions. Participants in the laboratory group were randomly assigned to nondeceptive (n = 28) or deceptive (n = 27) treatment groups, and a mock-crime scenario was used. The field participants were confirmed nondeceptive (n = 28) or deceptive (n = 39) criminal suspects who underwent polygraph examinations between 1993 and 1997. The results indicated that there were salient differences between field and similarly obtained laboratory polygraph response measures. However, accuracy of laboratory participants' classifications using logistic regression analysis was not significantly different from field participants' classification accuracy.

The neuropsychiatric sequelae of chronic Lyme disease remains unclear. This study sought to characterize the psychological status of a group of participants who met criteria for post-Lyme syndrome (PLS). These measures were then used to examine the influence of psychological status on neuropsychological performances. Thirty PLS participants completed a structured psychiatric interview, the Positive and Negative Affect Schedule, the Lyme Symptom Checklist, and a battery of neuropsychological tests. As a group, the PLS participants did not appear to have an elevated incidence of psychiatric disorders, and psychiatric history was not useful for understanding neuropsychological performances or symptom reports. The mood of the PLS participants was characterized by lowered levels of positive affect (PA) and typical levels of negative affect. This combination can be distinguished from depression and is consistent with previous findings of affect patterns in individuals with chronic fatigue syndrome. PA was also linked to both total symptom severity and severity of cognitive complaints, but not to duration of illness, neurological manifestations at initial diagnosis, or treatment history. Relative to published normative data, neuropsychological performances were not in the impaired range on any measure. Neither psychological status nor symptom report were useful for understanding any aspect of cognitive functioning. It is concluded that decreased PA is the most useful marker of psychological functioning in PLS.