Chetwyn C. H. Chan

Lie detection by functional magnetic resonance imaging

The accurate detection of deception or lying is a challenge to experts in many scientific disciplines. To investigate if specific cerebral activation characterized feigned memory impairment, six healthy male volunteers underwent functional magnetic resonance imaging with a block‐design paradigm while they performed forced‐choice memory tasks involving both simulated malingering and under normal control conditions. Malingering that demonstrated the existence and involvement of a prefrontal‐parietal‐sub‐cortical circuit with feigned memory impairment produced distinct patterns of neural activation. Because astute liars feign memory impairment successfully in testing once they understand the design of the measure being employed, our study represents an extremely significant preliminary step towards the development of valid and sensitive methods for the detection of deception. Hum. Brain Mapping 15:157–164, 2002.

Neural correlates of feigned memory impairment

While initial neuroimaging studies have provisionally identified activation in the prefrontal (including the anterior cingulate) and parietal regions during lying, the robustness of this neuroanatomical pattern of activation across forms of stimuli, genders, and mother tongues remains to be demonstrated. In this paper we report the results of three studies designed to test the reproducibility of the brain activation previously observed during feigned memory impairment. A total of twenty-nine right-handed participants, divided into three cohorts, participated in three different studies of feigned memory impairment. Findings indicate that bilateral activation of prefrontal and parietal regions was invariant across stimulus types, genders, and mother tongues, suggesting the general importance of these regions during malingering and possibly deception in general. In conjunction with earlier imaging findings, these three studies suggest that the prefrontal parietal network provides a robust neuroanatomical foundation upon which future dissimulation research may build.

Motivational Enhancement Therapy in Addition to Physical Therapy Improves Motivational Factors and Treatment Outcomes in People With Low Back Pain: A Randomized Controlled Trial

OBJECTIVES To examine whether the addition of motivational enhancement treatment (MET) to conventional physical therapy (PT) produces better outcomes than PT alone in people with chronic low back pain (LBP). DESIGN A double-blinded, prospective, randomized, controlled trial. SETTING PT outpatient department. PARTICIPANTS Participants (N=76) with chronic LBP were randomly assigned to receive 10 sessions of either MET plus PT or PT alone. INTERVENTION MET included motivational interviewing strategies and motivation-enhancing factors. The PT program consisted of interferential therapy and back exercises. MAIN OUTCOME MEASURES Motivational-enhancing factors, pain intensity, physical functions, and exercise compliance. RESULTS The MET-plus-PT group produced significantly greater improvements than the PT group in 3 motivation-enhancing factors; proxy efficacy (P<.001), working alliance (P<.001), and treatment expectancy (P=.011). Furthermore, they performed significantly better in lifting capacity (P=.015), 36-Item Short Form Health Survey General Health subscale (P=.015), and exercise compliance (P=.002) than the PT group. A trend of a greater decrease in visual analog scale and Roland-Morris Disability Questionnaire scores also was found in the MET-plus-PT group than the PT group. CONCLUSION The addition of MET to PT treatment can effectively enhance motivation and exercise compliance and show better improvement in physical function in patients with chronic LBP compared with PT alone.

Does intensive rehabilitation improve the functional outcome of patients with traumatic brain injury (TBI)? A randomized controlled trial

Objective: To evaluate the effects of an increase in the intensity of rehabilitation on the functional outcome of patients with traumatic brain injury (TBI). Design and methods: Sixty-eight patients (age 12–65 years) with moderate-to-severe TBI were included. They were randomized into high (4-hour/day) or control (2-hour/day) intensity rehabilitation programmes at an average of 20 days after the injury. The programmes ended when the patients achieved independence in daily activities or when 6 months had passed. Outcome and results: No significant differences were found in the Functional Independence Measure (FIM) (primary outcome) and Neurobehavioural Cognitive Status Examination (NCSE) total scores between the two groups. There were significantly more patients in the high intensity group than in the control group who achieved a maximum FIM total score at the third month (47% vs. 19%, p = 0.015) and a maximum Glasgow Outcome Scale (GOS) score at the second (28% vs. 8%, p = 0.034) and third months (34% vs. 14%, p = 0.044). Conclusions: Early intensive rehabilitation may improve the functional outcome of patients with TBI in the early months post-injury and hence increase the chance of their returning to work early. Intensive rehabilitation in this study speeded up recovery rather than changed the final outcome.

Evaluation of the chronic disease self-management program in a Chinese population

Abstract Objective This study evaluated the 6-week Chronic Disease Self-Management Program (CDSMP) in Hong Kong. Methods A total of 148 subjects with chronic illness were recruited. Subjects were matched on duration of illness and gender, and then randomly allocated to experimental and comparison groups. The experimental group participated in the CDSMP, while the comparison group joined a Tai-Chi interest class in a mass-activity format. Subjects completed evaluation questionnaires before beginning their program and 1 week following the program. Results Analysis of covariance showed that the CDSMP participants demonstrated significantly higher self-efficacy in managing their illness, used more cognitive methods to manage pain and symptoms, and felt more energetic than the subjects in the comparison group. The CDSMP participants also demonstrated changes in their profile of coping strategies, having a tendency to adopt the cognitive methods of diverting attention, reinterpreting pain, ignoring sensations, and making positive self-statements. Conclusion The short-term evaluation results showed that the CDSMP primarily increased the self-efficacy, exercise behavior, and application of cognitive coping strategies of the participants. Practice Implication The effect of the CDSMP in a Chinese population is similar to that found in studies in Western cultures, and the CDSMP could be applied effectively in a Chinese population.

Normative data for neuropsychological measures of fluency, attention, and memory measures for Hong Kong Chinese.

Normative information on neuropsychological measures for Chinese people is scarce. This study addresses this inadequacy by providing norms on several tests, using a sample of 475 Cantonese-speaking Chinese aged from 13 to 46. Included are eight neuropsychological measures of attention, memory, and fluency, which provided an overview of some important neuropsychological functions along the verbal-nonverbal axis. Age, gender, and education were factors observed to have an effect on the test performance of these participants. This pattern is consistent with that reported in Western literature. These measures appear to be appropriate clinical instruments for use in Hong Kong Chinese society, although the usefulness of the current norms is limited to adolescents and, to a lesser extent, to young adults in that population. Also, because of possibly important differences in the linguistic and educational backgrounds of Hong Kong residents versus Chinese residents of other countries (including mainland China and North America), applicability of the current norms outside of Hong Kong is currently uncertain.

The effect of the duration of exposure to the electromagnetic field emitted by mobile phones on human attention.

&NA; Previous findings suggested the facilitating effect of the electromagnetic field emitted by mobile phones on human attention. This study aimed to examine the relationship between the facilitating effect and the duration of exposure to the electromagnetic field emitted by mobile phones on human attention. Seventy‐eight university students were randomly assigned to either an experimental or a control group. Their performance in the administered attention tasks was compared. Participants in the experimental group performed better on one of the two measures of attention only after they had been exposed to the electromagnetic field emitted by the mobile phone for some time. The results seem to suggest that attention functions may be differentially enhanced after exposing to the electromagnetic field emitted by mobile phones. Furthermore, this transient facilitation effect might be dose dependent.

Effect on human attention of exposure to the electromagnetic field emitted by mobile phones

This study examined the effect of exposure to the electromagnetic field emitted by mobile phones on human attention. Three measures of attention were administered to 72 teenagers, 37 of whom were mobile phone users. The results showed that the mobile phone users performed better on one of the three measures of attention than did the non-mobile phone users. The results suggest that exposure to the electro- magnetic field emitted by mobile phones may have a mild facilitating effect on attention functions, which is consistent with previous observations that exposure to the electromagnetic field has a facilitating effect on cognitive processing. The possibility that mobile phone users may be naturally better at multiple tasking tasks was discussed.

ICF Core Set for vocational rehabilitation: results of an international consensus conference

Purpose: Vocational rehabilitation (VR) programs aim to facilitate work participation. However, there is no universal framework to describe the functioning of individuals who participate in VR. The objective of this paper is to report on the Core Set for VR based on the International Classification of Functioning, Disability and Health (ICF) by the World Health Organization (WHO). Methods: A formal decision-making and consensus-based process was conducted based on the evidence from four preparatory studies. Twenty-three international experts chosen by WHO Region and expertise in VR attended the consensus conference. Results: Ninety ICF categories were included in the comprehensive Core Set (activities and participation = 40, environmental factors = 33, body functions =  17), while the brief Core Set included 13 second-level categories (activities and participation = 6, environmental factors = 4, body functions =  3). Conclusions: The expert opinion and evidence-based Core Set could serve as an international standard for what to measure and report concerning functioning of individuals in VR. The Core Set could also provide a common language among clinicians, researchers, insurers, and policymakers in the implementation of successful VR. Further testing and validation studies are encouraged. Implications for Rehabilitation Vocational rehabilitation is a multidisciplinary and multi-stakeholder process, which aims to reduce or eliminate the burden of work disability and facilitate work participation. The International Classification of Functioning, Disability and Health (ICF) provides a framework to describe and measure the functioning of individuals who are in a vocational rehabilitation program. The ICF Core Set for vocational rehabilitation provides us with a list of functioning domains in our effort to examine vocational rehabilitation or return-to-work outcomes and the multiple factors associated with vocational rehabilitation. The ICF Core Set for vocational rehabilitation can be used in clinical rehabilitation setting and rehabilitation research, and further steps to ensure the robust measurement, documentation, and reporting of the Core Set in rehabilitation are being planned.

Motor relearning programme for stroke patients: a randomized controlled trial

Objective: To study the efficacy of the motor relearning approach in promoting physical function and task performance for patients after a stroke. Design: Matched-pair randomized controlled trial. Setting: An outpatient rehabilitation centre in Hong Kong. Participants: Fifty-two outpatients with either a thrombotic or haemorrhagic stroke who completed either the study or control group. Interventions: The patients received 18 2-h sessions in six weeks of either the motor relearning programme or a conventional therapy programme. Main outcome measures: The Berg Balance Scale, the Timed Up and Go Test, the Functional Independence Measure (FIM), the modified Lawton Instrumental Activities of Daily Living (IADL) test, and the Community Integration Questionnaire. Results: Patients in the motor relearning group showed significantly better performance on all but the Timed Up and Go Test when compared with the control group (F(1,150)=6.34-41.86, P ≤ 0.015). The interactions between group and occasion were significant on all five outcome measures, indicating that the rates of change across time between the motor relearning and control groups differed (F(3,150)=3.60-33.58, P < 0.015). Conclusion: The motor relearning programme was found to be effective for enhancing functional recovery of patients who had a stroke. Both ‘sequential’ and ‘function-based’ concepts are important in applying the motor relearning approach to the rehabilitation of stroke patients.