Multiple-electrode arrays are valuable both as a research tool and as a sensor for neuromotor prosthetic devices, which could potentially restore voluntary motion and functional independence to paralyzed humans. Long-term array reliability is an important requirement for these applications. Here, we demonstrate the reliability of a regular array of 100 microelectrodes to obtain neural recordings from primary motor cortex (MI) of monkeys for at least three months and up to 1.5 years. We implanted Bionic (Cyberkinetics, Inc., Foxboro, MA) silicon probe arrays in MI of three Macaque monkeys. Neural signals were recorded during performance of an eight-direction, push-button task. Recording reliability was evaluated for 18, 35, or 51 sessions distributed over 83, 179, and 569 days after implantation, respectively, using qualitative and quantitative measures. A four-point signal quality scale was defined based on the waveform amplitude relative to noise. A single observer applied this scale to score signal quality for each electrode. A mean of 120 (+/- 17.6 SD), 146 (+/- 7.3), and 119 (+/- 16.9) neural-like waveforms were observed from 65-85 electrodes across subjects for all recording sessions of which over 80% were of high quality. Quantitative measures demonstrated that waveforms had signal-to-noise ratio (SNR) up to 20 with maximum peak-to-peak amplitude of over 1200 microv with a mean SNR of 4.8 for signals ranked as high quality. Mean signal quality did not change over the duration of the evaluation period (slope 0.001, 0.0068 and 0.03; NS). By contrast, neural waveform shape varied between, but not within days in all animals, suggesting a shifting population of recorded neurons over time. Arm-movement related modulation was common and 66% of all recorded neurons were tuned to reach direction. The ability for the array to record neural signals from parietal cortex was also established. These results demonstrate that neural recordings that can provide movement related signals for neural prostheses, as well as for fundamental research applications, can be reliably obtained for long time periods using a monolithic microelectrode array in primate MI and potentially from other cortical areas as well.

These experiments examined the ability of the adult motor cortex to reorganize its relationship with somatic musculature following nerve lesions. Cortical motor output organization was assessed by mapping the areal extent of movements evoked by intracortical electrical stimulation in anesthetized rats. Output patterns of the motor cortex of normal rats were compared with those of adult rats that had received either a forelimb amputation or a facial motor nerve transection 1 week to 4 months earlier. In both experimental conditions the extent of some representations increased. Stimulation thresholds required to elicit movements in expanded representations were at or below normal levels. After forelimb amputation, the area from which shoulder movements could be evoked at low thresholds enlarged. Sectioning of the branches of the facial nerve that innervate the vibrissa musculature enlarged the motor cortex forelimb and eye/eyelid output areas; these enlargements appeared to occupy the former vibrissa area. These results indicate that the amount of cortex controlling a group of muscles and the strength of the relationship between a cortical locus with its target muscles is modified by nerve lesions in adult mammals. They also show that motor nerve lesions are sufficient to produce this change and that the changes can appear as early as 7 days following a peripheral nerve injury.

Objective: To determine if high fidelity simulation based team training can improve clinical team performance when added to an existing didactic teamwork curriculum. Setting: Level 1 trauma center and academic emergency medicine training program. Participants: Emergency department (ED) staff including nurses, technicians, emergency medicine residents, and attending physicians. Intervention : ED staff who had recently received didactic training in the Emergency Team Coordination Course (ETCCH) also received an 8 hour intensive experience in an ED simulator in which three scenarios of graduated difficulty were encountered. A comparison group, also ETCC trained, was assigned to work together in the ED for one 8 hour shift. Experimental and comparison teams were observed in the ED before and after the intervention. Design: Single, crossover, prospective, blinded and controlled observational study. Teamwork ratings using previously validated behaviorally anchored rating scales (BARS) were completed by outside trained observers in the ED. Observers were blinded to the identification of the teams. Results: There were no significant differences between experimental and comparison groups at baseline. The experimental team showed a trend towards improvement in the quality of team behavior (p = 0.07); the comparison group showed no change in team behavior during the two observation periods (p = 0.55). Members of the experimental team rated simulation based training as a useful educational method. Conclusion: High fidelity medical simulation appears to be a promising method for enhancing didactic teamwork training. This approach, using a number of patients, is more representative of clinical care and is therefore the proper paradigm in which to perform teamwork training. It is, however, unclear how much simulator based training must augment didactic teamwork training for clinically meaningful differences to become apparent.T eamwork training has made a fundamental impact on error reduction and human performance improvement in a number of commercial areas such as aviation 1 2 and other major industries. Aviation provides a good example of how simulation experts and human factors psychologists have collaborated to produce flight simulators that are intended to train and test both crew technical and human interaction skills. Medicine has had a long history of training and testing caregiver clinical skills and performance that is primarily individually oriented. As a result of traditional training and norms, physicians in particular tend to function autonomously. Some clinical tasks are easily simulated and are measurable in environments such as those used in Advanced Cardiac Life Support (ACLS) and Advanced Trauma Life Support (ATLS) courses. Less importance has been assigned to training and assessing teamwork skills. Despite the prominent role that teams play in delivering health care, opportunities to formally practise teamwork skills and receive expert feedback do not exist. A recent Institute of Medicine report 3 reminds u...

The potential for peripheral nerve iWjury to reorganize motor cortical representations was investigated in adult rats. Maps reflecting functional connections between the motor cortex and somatic musculature were generated with intracortical electrical stimulation techniques. Comparison of cortical somatotopic maps obtained in normal rats with maps generated from rats with a facial nerve lesion indicated that the forelimb and eye/eyelid representations expanded into the normal vibrissa area. Repeated testing from an electrode placed chronically in the motor cortex showed a shift from vibrissa to forelimb within hours after facial nerve transection. These comparatively quick changes in motor cortex representation pattern suggest that synaptic relations between motor cortex and somatic musculature are continually reshaped in adult mammals.The primary motor area of the cerebral neocortex (MI) is defined in a variety of mammals as the cerebral ineocortical area in which movements can be evoked at the lowest levels of electrical stimulation (1). MI is involved, either directly or through subcortical linkages, in the flexible and skilled control of somatic musculature (2, 3). Lesions of MI or damage to MI inputs or outputs compromises skilled motor performance and other motor functions (4-7). In some cases functional deficits recover with time, but aberrations in motor control may persist or worsen (8,9). Contributions to the control of related muscle groups appear to arise from a topographically localized region of MI. The stability of this topographical pattern in adult mammals is unclear, but alterations in the size, shape, and distribution of motor representations could alter the extent to which MI participates in motor control of various muscle groups over time.Recently, we demonstrated that the development of MI representation patterns can be altered by peripheral nerve lesions (10). By use of electrical stimulation mapping methods, forelimb amputation on the day of birth was shown to result in representations of remaining body parts that were larger than normally observed. This finding suggests that the development of motor representation patterns is dynamicone that is influenced by nerve injury and perhaps by selective forms of experience or deprivation. In developing sensory systems the potential for such factors to modify the normal organization of sensory representations is wellestablished. In some instances-namely, the development of ocular dominance of visual cortical neurons, modifications are restricted to a distinct "critical period" (11), whereas in other cases reorganization of intact sensory systems has been demonstrated following nerve lesions in immature and adult animals (12).In the present experiments we were interested to know if the potential for MI to alter its topographic relationships with muscles persists into adulthood, and if so, how rapidly these effects are expressed. In adult rats, the short-and long-term changes in MI organization were examined after a lesion was made to the m...

In the accompanying paper (Sanes et al. 1989), we demonstrated that the map of motor cortex (MI) output was reorganized when examined 1 week to 4 months after a motor nerve lesion in adult rats. The present experiments measured the extent of functional reorganization that occurs within the first hours after this lesion. Shifts in MI output were examined by testing the effect of stimulation at a site in MI vibrissa area before and up to 10 h after nerve section of the branches of the facial nerve that innervate the vibrissa. Immediately following nerve transection, no movement or forelimb EMG activity was evoked by intracortical electrical stimulation within the vibrissa area. Within hours of the nerve transection, however, stimulation elicited forelimb EMG responses that were comparable to those obtained by stimulating within the pre-transection forelimb area. Remapping of MI after nerve transection indicated that the forelimb boundary had shifted about 1 mm medially from its original location into the former vibrissa territory. Forelimb EMG could be evoked for up to 10 h within this reorganized cortex. These results indicated that the output circuits of MI can be quickly reorganized by nerve lesions in adult mammals.

We investigated Turkish emergency physicians' views regarding family witnessed resuscitation (FWR) and to determine the current practice in Turkish academic emergency departments with regard to family members during resuscitation. A national cross-sectional, anonymous survey of emergency physicians working in academic emergency departments was conducted. Nineteen of the 23 university-based emergency medicine programs participated in the study. Two hundred and thirty-nine physicians completed the survey. Of the respondents, 83% did not endorse FWR. The most common reasons for not endorsing FWR was reported as higher stress levels of the resuscitation team and fear of causing physiological trauma to family members. Previous experience, previous knowledge in FWR, higher level of training and the acceptance of FWR in the institution where the participant works were associated with higher rates of FWR endorsement for this practice among emergency physicians.

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