Supplemental vibrotactile feedback control of stabilization and reaching actions of the arm using limb state and position error encodings

Abstract Background Deficits of kinesthesia (limb position and movement sensation) commonly limit sensorimotor function and its recovery after neuromotor injury. Sensory substitution technologies providing synthetic kinesthetic feedback might re-establish or enhance closed-loop control of goal-directed behaviors in people with impaired kinesthesia. Methods As a first step toward this goal, we evaluated the ability of unimpaired people to use vibrotactile sensory substitution to enhance stabilization and reaching tasks. Through two experiments, we compared the objective and subjective utility of two forms of supplemental feedback – limb state information or hand position error – to eliminate hand position drift, which develops naturally during stabilization tasks after removing visual feedback. Results Experiment 1 optimized the encoding of limb state feedback; the best form included hand position and velocity information, but was weighted much more heavily toward position feedback. Upon comparing optimal limb state feedback vs. hand position error feedback in Experiment 2, we found both encoding schemes capable of enhancing stabilization and reach performance in the absence of vision. However, error encoding yielded superior outcomes - objective and subjective - due to the additional task-relevant information it contains. Conclusions The results of this study have established the immediate utility and relative merits of two forms of vibrotactile kinesthetic feedback in enhancing stabilization and reaching actions performed with the arm and hand in neurotypical people. These findings can guide future development of vibrotactile sensory substitution technologies for improving sensorimotor function after neuromotor injury in survivors who retain motor capacity, but lack proprioceptive integrity in their more affected arm

Scientist-practitioner training at the internship and postdoctoral level: Reflections over three decades

Clinical psychology training for research-oriented scientist-practitioners tends to have a gap in research training during the predoctoral internship year. In 1982, the Clinical Psychology Training Program (CPTP) at the University of California, San Francisco (UCSF) began a 2-year clinical and clinical research training program combining an American Psychology Association (APA)-accredited internship and a postdoctoral fellowship. The goal of the program is to prepare graduates for leadership roles as principal investigators who are licensed clinicians able to function as independent practitioners. This article conveys the philosophy behind the program, its structure, and the results of the program over the last 31 years. The CPTP accepted 142 trainees, of whom 46 (32%) were minorities and 78 (55%) were women. CPTP fellows have published over 250 articles, chapters, and books with their mentors and have contributed to submitting research grants with them. The vast majority continued research and academic activities after graduation. The most recent self-study for APA accreditation reported that of 43 trainees admitted in the 10 years between 1999 and 2008, 41 (95%) went on to academic positions, research, or clinical positions in academic settings or research positions in other settings; 1 obtained a clinical position; and 1 provided no information. The program serves as a model for clinical psychology nationally, allowing for uninterrupted clinical research training during the internship and postdoctoral years, nurturing clinical psychologists committed to clinical research careers, and contributing substantially to the clinical research productivity of the host department