Who is exaggerating cognitive impairment and who is not?

This chart review examined the effects of effort on neuropsychological assessment and test performance patterns among genuine and exaggerating patients, with and without neurological findings, as aids to diagnosing symptom exaggeration. The sample consisted of 561 consecutive patients involved in compensation claims. With a flexible neuropsychological test (NPT) battery, the claims were assessed over 2 days. The sample included 303 patients evaluated for traumatic brain injury, 55 patients with neurological disease, and 203 patients assessed for other conditions (eg, depression or chronic pain). An average of 38 ability measures per patient were used to generate an overall NPT domain score. Composite scores were also computed for symptom validity tests, self-report measures of psychiatric symptoms, and memory complaint inventory. Seven NPT cognitive subdomain scores were multiply regressed onto the symptom validity test composite, accounting for 45% of its total variance. Patients were also assigned to Genuine or Exaggerator groups based on symptom validity test performance. The NPT for Exaggerating patients averaged 1.43 standard deviations below that of Genuine patients, suggesting that NPT scores for most Exaggerating patients are underestimates of their true ability. Factor analysis results differed between these groups. As a result, clinicians might avoid falsely identifying genuine patients as exaggerating by incorporating their self-reports of psychiatric symptoms and memory complaints into the diagnostic process.     

The generalization of deferred imitation in enculturated chimpanzees (Pan troglodytes)

Deferred imitation of object-related actions and generalization of imitation to similar but not identical tasks was assessed in three human-reared (enculturated) chimpanzees, ranging in age from 5 to 9 years. Each ape displayed high levels of deferred imitation and only slightly lower levels of generalization of imitation. The youngest two chimpanzees were more apt to generalize the model's actions when they had displayed portions of the target behaviors at baseline, consistent with the idea that learning is more likely to occur when working within the "zone of proximal development." We argue that generalization of imitation is the best evidence to date of imitative learning in chimpanzees. Electronic Publication     

Shepherd Ivory Franz: His contributions to neuropsychology and rehabilitation

Shepherd I. Franz was an important figure in psychology of the last century, and historians of psychology have given recognition to much of his work. However, his experimental work with animals and his pioneer investigations in experimental and clinical neuropsychology have been largely ignored. This article reviews his conceptual, assessment, and treatment contributions, including (1) his pioneering work on the use of learned behavior as a baseline for the study of cerebral ablations, (2) his interest in brain plasticity, (3) his development of comprehensive psychological assessment methods, and (4) his work on the rehabilitation of neurological patients with techniques derived from his animal experiments. His work predated much of what is now part of the conceptual substance of the experimental and clinical neurosciences.     

Review of quantity and types of spirituality research in three health care databases (1962-1999): implications for the health care ministry

Using computer technology to identify the term "spiritual," these researchers present results of the 2306 citations and compare five criteria discovered with research reported in four pastoral counseling journals. The authors note the limitations of such a search and the possible implications of the findings for health care ministry.     

Color discrimination under chronic hypoxic conditions (simulated climb "Everest-Comex 97")

Hypoxia is known to alter visual functions. In the present study, the effects of chronic hypobaric hypoxia upon visual color discrimination were studied in 8 subjects participating in a simulated climb from sea level (PO2 = 210 hPa) to 8,848 m (PO2 = 70 hPa) over a 31-day period of confinement in a decompression chamber ('Everst-Comex 97'). During these investigations, the subjects were required to discriminate between colors of different hue in the red, blue, and green ranges. Alterations in color discrimination increased slightly but significantly as altitude increased. Impairments occurred mainly in the red and blue ranges. In addition, our results further indicate that color discrimination would be affected only when a minimum threshold of difference between color stimuli is not present. Methodological and physiological implications are discussed.     

Perceptual anticipation in handwriting: the role of implicit motor competence

In two experiments, perceptual anticipation--that is, the observer's ability to predict the course of dynamic visual events--in the case of handwriting traces was investigated. Observers were shown the dynamic display of the middle letter l excerpted from two cursive trigrams (lll or lln) handwritten by one individual. The experimental factor was the distribution of the velocity along the trace, which was controlled by a single parameter, beta. Only for one value of this parameter (beta = 2/3) did the display comply with the two-thirds power law, which describes how tangential velocity depends on curvature in writing movements. The task was to indicate the trigram from which the trace was excerpted--that is, to guess the letter that followed the specific instance of the l that had been displayed. In Experiment 1, the no answer option was available. Experiment 2 adopted a forced-choice response rule. Responses were never reinforced. When beta = 2/3, the rate of correct guesses was high (Experiment 1, P?correct? = .69; Experiment 2, P?correct? = .78). The probability of a correct answer decreased significantly for both smaller and larger values of beta, with wrong answers becoming predominant at the extremes of the range of variation of this parameter. The results are consistent with the hypothesis that perceptual anticipation of human movements involves comparing the perceptual stimulus with an internal dynamic representation of the ongoing event.     

The perceived position of the hand in space

This paper reports a series of experiments of the perceived position of the hand in egocentric space. The experiments focused on the bias in the proprioceptively perceived position of the hand at a series of locations spanning the midline from left to right. Perceived position was tested in a matching paradigm, in which subjects indicated the perceived position of a target, which could have been either a visual stimulus or their own fingertip, by placing the index finger of the other hand in the corresponding location on the other side of a fixed surface. Both the constant error, or bias, and the variable error, or consistency of matching attempts, were measured. Experiment 1 showed that (1) there is a far-left advantage in matching tasks, such that errors in perceived position are significantly lower in extreme-left positions than in extreme-right positions, and (2) there is a strong hand-bias effect in the absence of vision, such that the perceived positions of the left and right index fingertips held in the same actual target position in fact differ significantly. Experiments 2 and 3 demonstrated that this hand-bias effect is genuinely due to errors in the perceived position of the matched hand, and not to the attempt at matching it with the other hand. These results suggest that there is no unifying representation of egocentric, proprioceptive space. Rather, separate representations appear to be maintained for each effector. The bias of these representations may reflect the motor function of that effector.     

Role of the working alliance in the treatment of delinquent boys in community-based programs

Examined the role of the working alliance in the treatment of delinquent boys in community-based residential programs, clarifying the relation between therapeutic process and behavioral change. Horvath and Greenberg's (1989) Working Alliance Inventory was used to assess the therapeutic alliance between youth and staff after 3 weeks in treatment and again after 3 months. Achenbach's (1991) Child Behavior Checklist (CBCL; Youth Self-Report [YSR] and Teacher Report Form [TRF]) and recidivism scores were used to assess treatment progress and outcome. Results indicated that a positive working alliance assessed after 3 months in treatment related to positive psychological changes and predicted lower rates of recidivism. Unexpectedly, a positive working alliance assessed early in treatment was associated with negative outcomes (increased internalizing and externalizing symptoms and higher rates of recidivism). This finding suggests that for some delinquent youth initially optimistic assessments may be prognostic of slow progress or treatment failure.     

Post-decision consolidation: group members in different social settings compared to individual decision makers

Two experiments were conducted to examine how making decisions in a 3-member group affects the degree of post-decision consolidation, defined as attractiveness changes in favor of the chosen alternative. Both experiments were conducted in two sessions one week apart. In the first session (decision phase), participants estimated the importance of each of four different attributes describing two decision alternatives. They were then shown predetermined attractiveness ratings on each of the attributes and were to decide on the two alternatives, either individually or as a group. In the second session (post-decision phase), the participants were to attempt to recall the attractiveness ratings for the attributes as presented to them in session one. In both experiments, significant post-decision consolidation was found for individual decision makers but not for group members. In experiment 2, this result was replicated, no difference in consolidation being found between group members with face-to-face interaction and without.