Design and validation of a MR-compatible pneumatic manipulandum

The combination of functional MR imaging and novel robotic tools may provide unique opportunities to probe the neural systems underlying motor control and learning. Here, we describe the design and validation of a MR-compatible, 1 degree-of-freedom pneumatic manipulandum along with experiments demonstrating its safety and efficacy. We first validated the robot's ability to apply computer-controlled loads about the wrist, demonstrating that it possesses sufficient bandwidth to simulate torsional spring-like loads during point-to-point flexion movements. Next, we verified the MR-compatibility of the device by imaging a head phantom during robot operation. We observed no systematic differences in two measures of MRI signal quality (signal/noise and field homogeneity) when the robot was introduced into the scanner environment. Likewise, measurements of joint angle and actuator pressure were not adversely affected by scanning. Finally, we verified device efficacy by scanning 20 healthy human subjects performing rapid wrist flexions against a wide range of spring-like loads. We observed a linear relationship between joint torque at peak movement extent and perturbation magnitude, thus demonstrating the robot's ability to simulate spring-like loads in situ. fMRI revealed task-related activation in regions known to contribute to the control of movement including the left primary sensorimotor cortex and right cerebellum.     

Usability study and pilot validation of a computer-based emotion recognition test for older adults with Alzheimer's disease and amnestic mild cognitive impairment

Objectives: This study aimed to carry out a pilot validation of Affect-GRADIOR, a computer-based emotion recognition test, with older adults. The study evaluated its usability, reliability and validity for the screening of people with Alzheimer´s disease (AD) and amnestic mild cognitive impairment (aMCI).

Methods: The test was administered to 212 participants (76.37 ± 6.20 years) classified into three groups (healthy controls, n = 69; AD, n = 84; and aMCI, n = 59) on the basis of detailed neurological, neuropsychological, laboratory and neuro-imaging evidence. Data on usability were collected by means of a questionnaire and automated evaluation.

Results: The validated test comprised 53 stimuli and 7 practice items (one per emotion). Participants reported that Affect-GRADIOR was accessible and user-friendly. It had high internal consistency (ordinal Cronbach's α = 0.96). Test-retest reliability correlations were significant and robust (r = 0.840, p < 0.001). Exploratory factor analysis supported a seven-factor model of the emotions assessed (neutral expression, happiness, surprise, disgust, sadness, anger and fear). Receiver operating characteristic curve analyses suggested that the test discriminated healthy older adults from AD and aMCI cases. Correct answer score improved MMSE predictive power from 0.547 to 0.560 (Cox & Snell R², p = 0.012), and Affect-GRADIOR speed of processing score improved MMSE predictive power from 0.547 to 0.563 (Cox & Snell R², p = 0.010).

Conclusions: Affect-GRADIOR is a valid instrument for the assessment of the facial recognition of emotions in older adults with and without cognitive impairment.     

Use of a computer-based application in a pediatric hemodialysis unit: a pilot study

This report describes preliminary efforts to implement a computer-based application, called Zora, in a pediatric hemodialysis unit. The feasibility and safety of establishing a virtual community in the hemodialysis unit are explored. Zora allows users to design and inhabit a graphical virtual city where they create characters, stories and spaces while communicating in real-time. Over a 5-month period, 7 hemodialysis patients and 4 unit staff found Zora enjoyable and safe. The results support the premise that computational environments may offer an opportunity for pediatric patients and their caregivers to participate in virtual communities that promote coping with chronic physical illnesses.     

The sensitivity and psychometric properties of a brief computer-based cognitive screening battery in a depression clinic

At present, there is poor accuracy in assessing cognitive and vegetative symptoms in depression using clinician or self-rated measures, suggesting the need for development of standardized tasks to assess these functions. The current study assessed the psychometric properties and diagnostic specificity of a brief neuropsychological screening battery designed to assess core signs of depression; psychomotor retardation, attention and executive functioning difficulties, and impaired emotion perception within an outpatient psychiatry setting. Three hundred eighty-four patients with mood disorders and 77 healthy volunteers participated. A large percentage of patients met diagnostic criteria for Major Depressive Disorder alone (49%) or with another comorbid psychiatric disorder (24%). A brief, 25-min battery of computer-based tests was administered to control participants and patients measuring the constructs of inhibitory control, attention, visual perception, and both executive and visual processing speed. The patient groups performed significantly worse than the control group regardless of diagnosis on visual perception and attention accuracy and processing speed factors. Surprisingly, the anxiety disorder group performed better than several other psychiatric disorder groups in inhibitory control accuracy. Developing valid and reliable measures of cognitive signs in mood disorders creates excellent opportunities for tracking cognitive status prior to initiation of treatment, and allows for reliable retest following treatment.     

Development of a computer-based behavioral assessment of checking behavior in obsessive-compulsive disorder

Objective

The goal of the current study was to develop and obtain preliminary psychometric data for a computer-based behavioral measure of compulsive checking behavior in a sample of patients with obsessive-compulsive disorder (OCD).

Method

We examined performance on a novel behavioral measure in 30 patients with OCD and 27 matched healthy controls. In the computerized assessment, participants navigated through two virtual environments (home and office) using a joystick and head-mounted display. The experiment consisted of three phases: training, distraction, and the main task. After the training and distraction phases, participants were instructed to check the virtual environments freely as if they were in their natural environment. Primary dependent variables in the current study included several indices of frequency and duration of checking behaviors. We examined construct validity for the task by comparing the novel behavioral measures with standardized self-report and interviewer-rated measures.

Results

Results indicated that (1) OCD patients demonstrated significantly greater problems with compulsive checking compared to controls, and (2) performance on the task was positively correlated with both self-reported symptoms and interviewer-rated measures associated with OCD.

Conclusions

This study provides preliminary data to support the use of this task as a new possible behavioral measure of compulsive checking behavior in OCD. If we merge the traditional behavioral research with this novel and ecologically valid method, it could improve the assessment of OCD in both clinical and research setting.     

Reliability of a computer-based neurobehavioral assessment test battery for Bangladeshi adolescent children

In developing countries, there is a need for low-cost neurobehavioral (NB) test batteries for vulnerable populations, particularly for children exposed to environmental neurotoxicants. The objective of the current study was to assess the feasibility and test-retest reliability of the Behavioral Assessment and Research System (BARS) in children from a rural community in Bangladesh. Fifty healthy adolescents living in the Health Effects of Arsenic Longitudinal Study (HEALS) area in Araihazar, Bangladesh completed all six tests from the BARS in two test sessions scheduled two weeks apart. The BARS tests evaluated NB functions such as motor coordination, attention, memory, and information processing speed. The reliability assessment, evaluated by test-retest correlations demonstrated moderate to strong correlations (i.e., correlation coefficients ranged from 0.43 to 0.85), which were statistically significant (p < 0.05). Paired t-tests for comparing the test and retest outcomes indicated significant improvement in NB performance, highlighting learning and practice effects. NB performance improved with increasing age in most cases. Adolescent boys performed better than the girls in Finger Tapping, Digit Span, and Simple Reaction Time, whereas the girls performed better in Continuous Performance and Symbol Digit tests. The reliability scores (Pearson’s correlations 0.43−0.85) were consistent with other children studies in different cultural settings. The effects of age and sex on NB tests were also consistent with findings reported in other countries. Overall, the findings of the study support the feasibility of using this computer-based test system to assess vulnerability of brain health due to environmental exposures among rural Bangladeshi children.     

Lithium Information Center. One model of a computer-based psychiatric information service

The Lithium Information Center has been functioning as a specialized psychiatric information service for nearly ten years. Over the years, the center has disseminated information about the medical uses of lithium to psychiatrists and other physicians, to patients, to the family and friends of patients, and to a host of other individuals and organizations including pharmacists, lawyers, nurses, social workers, mental health centers, clinics, and support groups. To encourage the development of similar psychiatric information services, we outline the center's methods of acquiring, organizing, and disseminating lithium information.     

Effectiveness of a computer-based interactive eating disorders prevention program at long-term follow-up

Computer-based delivery of health-related psychoeducational programming is increasingly popular. In the present study, 72 non-symptomatic undergraduate women were randomized to an Internet-based prevention program for eating disorders with or without accompanying discussion groups, or a control group. Sixty-one of the women (84%) completed the Student Bodies program, and were assessed at short and eight-nine month follow-up. Participation in the program resulted in better outcomes across all groups compared to controls, and women in the unmoderated discussion group appeared to have the most reduction in risk. Benefits of the program continued at follow-up. Decrease in risk also was associated with time spent using the Internet-based program. The present study suggests that the use of Student Bodies may reduce risk of eating and body image concerns over the long term, and that moderation of discussion groups may not be essential for successful outcomes. Further research on larger samples will help determine the degree to which discussion groups or the Student Bodies program alone are effective.     

Partner-matching for the automated identification of reproducible ICA components from fMRI datasets: algorithm and validation

The analysis of functional magnetic resonance imaging (fMRI) data is complicated by the presence of a mixture of many sources of signal and noise. Independent component analysis (ICA) can separate these mixtures into independent components, each of which contains maximal information from a single, independent source of signal, whether from noise or from a discrete physiological or neural system. ICA typically generates a large number of components for each subject imaged, however, and therefore it generates a vast number of components across all of the subjects imaged in an fMRI dataset. The practical implementation of ICA has been limited by the difficulty in discerning which of these many components are spurious and which are reproducible, either within or across individuals of the dataset. We have developed a novel clustering algorithm, termed "Partner-Matching" (PM), which identifies automatically the independent components that are reproducible either within or between subjects. It identifies those components by clustering them according to robust measures of similarity in their spatial configurations either across different subjects of an fMRI dataset, within a single subject scanned across multiple scanning sessions, or within an individual subject scanned across multiple runs within a single scanning session. We demonstrate the face validity of our algorithm by applying it to the analysis of three fMRI datasets acquired in 13 healthy adults performing simple auditory, motor, and visual tasks. From among 50 independent components generated for each subject, our PM algorithm automatically identified, across all 13 subjects, components representing activity within auditory, motor, and visual cortices, respectively, as well as numerous other reproducible components outside of primary sensory and motor cortices, in functionally connected circuits that subserve higher-order cognitive functions, even in these simple tasks.     

Design and validation of a closed-loop,motor-activated auricular vagus nerve stimulation (MAAVNS) system for neurorehabilitation

BackgroundStudies have found that pairing vagus nerve stimulation (VNS) with motor activity accelerates cortical reorganization. This synchronous pairing may enhance motor recovery.ObjectiveTo develop and validate a motor-activated auricular vagus nerve stimulation (MAAVNS) system as a potential neurorehabilitation tool.MethodsWe created MAAVNS and validated its function as part of an ongoing clinical trial investigating whether taVNS-paired rehabilitation enhances oromotor learning. We compared 3 different MAAVNS EMG electrode configurations in 3 neonates. The active lead was placed over the buccinator muscle. Reference lead placements were orbital, temporal or frontal.ResultsThe frontal reference lead produced the highest sensitivity (0.87 ± 0.07 (n = 8)) and specificity (0.64 ± 0.13 (n = 8)). Oral sucking reliably triggers MAAVNS stimulation with high confidence.ConclusionEMG electrodes placed on target orofacial muscles can effectively trigger taVNS stimuli in infants in a closed loop fashion.     

Design of a multiple kernel learning algorithm for LS-SVM by convex programming

As a kernel based method, the performance of least squares support vector machine (LS-SVM) depends on the selection of the kernel as well as the regularization parameter (Duan, Keerthi, & Poo, 2003). Cross-validation is efficient in selecting a single kernel and the regularization parameter; however, it suffers from heavy computational cost and is not flexible to deal with multiple kernels. In this paper, we address the issue of multiple kernel learning for LS-SVM by formulating it as semidefinite programming (SDP). Furthermore, we show that the regularization parameter can be optimized in a unified framework with the kernel, which leads to an automatic process for model selection. Extensive experimental validations are performed and analyzed.     

The effects of a computer-based cognitive and physical training program in a healthy and mildly cognitive impaired aging sample

Objectives: The Long Lasting Memories (LLM) program concerns a newly integrated platform which combines cognitive exercises with physical activity within the context of advanced technologies. The main objective of this study was to present the preliminary results that determine the possible effectiveness of the LLM program in the improvement of cognitive functions and symptoms of depression in healthy elderly and subjects with mild cognitive impairment (MCI). Method: Fifty healthy and MCI subjects participated in the study. All of them received one hour's physical training and 35 minutes’ cognitive training, 3 times a week, during the 12 weeks of the program. Before and after the intervention all participants were assessed using a battery of neuropsychological tests.Results: The results showed a significant improvement after the LLM training in global cognitive function, in verbal memory, in attention, in episodic memory and symptoms of depression. Conclusion: This study indicates that LLM is a promising solution for older adults with and without cognitive impairment, maintaining their wellbeing with few professional and technical requirements.     

Depression experience journal: a computer-based intervention for families facing childhood depression

OBJECTIVE: This study tested the feasibility and safety of a computer-based application for families facing childhood depression. The Depression Experience Journal (EJ) is a psychoeducational intervention based on a narrative model involving the sharing of personal stories about childhood depression. METHOD: Semistructured interviews assessed Depression EJ feasibility and safety. Thirty-eight primary caretakers of children with depression (one caretaker per patient) used the EJ during a psychiatric hospitalization. Assessment of feasibility and safety was measured before EJ use and 2 to 4 weeks afterward. RESULTS: Results revealed that the EJ was safe and useful for decreasing social isolation, increasing hope, increasing understanding of familial feelings about childhood depression, and fostering positive reactions in caretakers. CONCLUSIONS: Computer-based interventions hold significant promise in providing a new manner of psychosocial support to families facing child and adolescent psychiatric illnesses.     

Assessment of a six-week computer-based remediation program for social cognition in chronic schizophrenia

Background

Programs to remediate cognitive deficits have shown promising results in schizophrenia, but remediation of social cognition deficits is less well understood. Social cognitive deficits may cause more disability than the widely recognized neurocognitive deficits, suggesting that this is an area worthy of further investigation.

Aim

Implement and evaluate a brief computerized cognitive remediation program designed to improve memory, attention, and facial affect recognition (FAR) in outpatients with chronic schizophrenia.

Methods

Baseline assessments of FAR and of clinical, cognitive, and psychosocial functioning were completed on 20 males with schizophrenia enrolled in an outpatient rehabilitation program at the Shanghai Mental Health Center (the intervention group) and on 20 males with schizophrenia recruited from among regular outpatients at the Center (the control group). Both groups received treatment as usual, but the intervention group also completed an average of 12.7 sessions of a computer-based remediation program for neurocognitive, social, and FAR functioning over a 6-week period. The baseline measures were repeated in both groups at the end of the 6-week trial.

Results

There were no statistically significant differences in the changes in clinical symptoms (assessed by the Positive and Negative Syndrome Scale, PANSS) or cognitive measures (assessed using the Hong Kong List Learning Test and the Letter-Number Sequencing Task) between the intervention and control groups over the 6-week trial, but there were modest improvements on the PANSS for the intervention group between baseline and after the intervention. There was a significantly greater improvement in the social functioning measure (the Personal and Social Performance scale, PSP) in the intervention group than in the control group. The pre-post change in the total facial recognition score in the intervention group was statistically significant (paired t-test=-2.60, p=0.018), and there was a statistical trend of a greater improvement in facial recognition in the intervention group than in the control group (F_(1,37)=2.93; p=0.092).

Conclusion

Integration of FAR training with a short, computer-administrated cognitive remediation program may improve recognition of facial emotions by individuals with schizophrenia, and, thus, improve their social functioning. But more work on developing the FAR training modules and on testing them in larger, more diverse samples will be needed before this can be recommended as a standard part of cognitive remediation programs.