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Biomedical subjects

B S Brucker

Publications and source records attributed to B S Brucker.

10 recordsLinked to original sources
PubMed1996

Biofeedback effect on electromyography responses in patients with spinal cord injury.

OBJECTIVE: To determine if electromyography (EMG) biofeedback procedures using an operant conditioning paradigm could significantly increase voluntary EMG responses from the triceps muscles of long term cervical spinal cord injured individuals. DESIGN: Intervention study with before-after trial measurement with each subject as its own control. SETTING: University outpatient clinic. PARTICIPANTS: One hundred individuals with cervical spinal cord injuries C6 or higher that were greater than 1-year duration, and who had less than normal strength and recordable EMG activity from the triceps, and who had reached a plateau in return of function. The first 100 individuals meeting this criteria who presented sequentially for EMG testing and biofeedback were included. No subjects were deleted from the sample. INTERVENTION: Muscle strength and surface EMG recording during attempts at elbow extension were obtained. The EMG pretest data were derived from the highest average recorded voluntary EMG response from the triceps during elbow extension. One 45-minute treatment session of EMG biofeedback for the triceps in an operant conditioning paradigm was provided for each of the 100 subjects. Seventy-five subjects received an average of 3 additional biofeedback treatment sessions. The posttest EMG data were derived from EMG measurements of the triceps during attempts at elbow extension from the 45-minute biofeedback treatment session and from the last additional biofeedback treatment session in a similar manner to the pretest procedures. MAIN OUTCOME MEASURES: A significant increase in EMG activity occurred from the triceps (p < or = .001) after one biofeedback treatment session and further significant increases in EMG activity occurred after additional biofeedback treatment sessions (p < or = .001). Initial muscle strength and initial EMG levels were not determining factors for response to the biofeedback. CONCLUSIONS: The results suggest the efficacy of biofeedback for increasing voluntary EMG responses in long term spinal cord injury patients.

Adolescent↗
PubMed1990

Motor units in incomplete spinal cord injury: electrical activity, contractile properties and the effects of biofeedback.

The electrical and contractile properties of hand muscles in a selected population of quadriplegic subjects were studied intensively before and after EMG biofeedback. Spontaneously active motor units and units that could only be slowly and weakly activated were observed in these subjects, in addition to units that were voluntarily activated normally. This suggests a considerable overlap of surviving motor neurons to a single muscle that are below, near or above the level of a lesion. Despite the common occurrence of polyphasic potentials and other signs of neuromuscular reinnervation, the average twitch tension of single motor units in hand muscles of quadriplegic subjects was not significantly different from that in control subjects. Nor did it increase after biofeedback training that typically increased the peak surface EMG by a factor of 2-5 times. The percentage of spontaneously active units was also constant. The surface EMG may be increased during biofeedback by using higher firing rates in motor units that can already be activated, rather than by recruiting previously unavailable motor units.

Adult↗
PubMed1990

Rehabilitation therapy for patients with long-term spinal cord injuries.

The functional effects of three types of therapy for subjects with long-term incomplete cervical spinal cord injuries were investigated. Men and women, aged 18 to 45 years, were assigned to one of four groups using a restricted randomization process. The training period was divided into two consecutive eight-week time blocks where subjects received either (1) supervised physical exercise therapy (PET), (2) neuromuscular stimulation (NMS), or (3) electromyographic (EMG) biofeedback. Group 1 received EMG biofeedback followed by PET; Group 2 received EMG biofeedback followed by NMS; Group 3 received NMS followed by PET; and Group 4 received 16 weeks of PET. Dependent measures (manual muscle tests, self-care scores, mobility measures, and voluntary EMG activity) were assessed before training, at eight weeks, and after 16 weeks of training. A significant improvement (p less than .05) across time was found on all dependent measures except voluntary EMG. No difference was found on comparisons between groups.

Adolescent↗
PubMed1978

Reflex conditioning in a spinal man.

A man with a completely transected spinal cord and a spastic neurogenic bladder was conditioned to void upon the presentation of an external stimulus. A classical conditioning paradigm was employed in which strong abdominal shock (unconditioned stimulus) was paired with an initially neutral mild electrical stimulation of the thigh (conditioned stimulus; CS). After the pairing trials, a reliable conditioned response of urination was elicited by the CS alone. The conditioned response did not extinguish over time, and the procedure left the bladder with clinically safe residual amounts of urine. Practical implications of the conditioning technique for the treatment of spastic neurogenic bladder conditions in spinally injured patients are discussed, as is the theoretical significance of conditioning at the reflex level in the absence of cortical involvement.

Abdominal Muscles↗
PubMed1978

Conditioned responding of the neurogenic bladder.

Classical conditioning techniques were employed to condition responding of the spastic neurogenic bladder in a man with quadriparesis and urinary incontinence secondary to spinal cord injury at the cervical level. A neutral stimulus of mild electrical stimulation to the thigh was paired temporally with an unconditioned stimulus (UCS) of stronger electrical stimulation of the lower abdomen, and then was presented alone as a conditioned stimulus (CS) to elicit the conditioned response (CR) of voiding. The previously neutral CS reliably elicited large amounts of urine and left little residual urine in the subject's bladder. Following the experimental sessions, the subject self-applied the CS on a predetermined schedule during his daily routine outside of the laboratory. The CS initially was successful, but after several days the CR exhibited extinction. Additional CS-UCS pairing sessions did not reinstate the responses satisfactorily. Aspects of the experimental procedure and the results are discussed as well as the feasibility of conditioning the human spinal cord in the absence of an intact central nervous system

Abdomen↗
PubMed1977

Biofeedback as an experimental treatment for postural hypotension in a patient with a spinal cord lesion.

A man having severe postural hypotension resulting from a spinal cord lesion at level T3, was trained to raise and lower his blood pressure with the use of biofeedback. The procedure consisted of 11 learning sessions during which the subject's task was to effect specific changes of his blood pressure without skeletal muscle or respiratory involvement. Blood pressure was continuously monitored and reported to the subject, and positive verbal reinforcement for correct changes was also supplied. Analysis of the results revealed that the subject had learned to produce large voluntary changes in pressure. This learned ability was then applied in a standing position resulting in counteracting the postural hypotension. Suggestions for further research and implications for clinical applications are discussed.

Adult↗
PubMed1977

Conditioning bladder responses in patients with spinal cord lesions.

Two patients with spinal cord lesions and spastic neurogenic bladders were treated with classical conditioning techniques to reinstate independent bladder function utilizing electrical stimulation of the abdomen as the unconditioned stimulus and mild electrical stimulation of the thigh as the conditioned stimulus. Successful conditioning was achieved in both cases. Urination was brought under the control of a previously neutral stimulus with a high rate of responding.

Adult↗
PubMed1976

Verbal discrimination learning as a function of brain damage, aging, and institutionalization.

The relationship between young non-brain-damaged nonpatients, elderly non-brain-damaged patients and elderly brain-damaged patients and the acquisition and extinction of verbal discrimination conditioned responses were investigated in this study. Four groups of 10 Ss each were used: one group of elderly brain-damaged patients with no speech impairment; one group of elderly non-brain-damaged patients; and one group of young nonpatient Ss used as a comparison group. The three elderly, brain-damaged and non-brain-damaged groups were unable to make a simple verbal discrimination, while the younger nonpatient group had a nearly perfect record of discrimination responses. No significant differences were obtained between the three elderly patient groups.

Adult↗