The effects of electromyographic feedback training on suppression of the oral-lingual movements associated with tardive dyskinesia

The efficacy of electromyographic feedback training in reducing the magnitude and frequency of the oral-lingual movements associated with tardive dyskinesia (TD) was investigated in a groups design. Twenty adult male inpatients diagnosed as having TD using the Abnormal Involuntary Movements Scale (AIMS) were randomly assigned to one of two treatment conditions. Following identification, all participants were initially reduced to the lowest effective dosage of neuroleptics, and then discontinued from anticholinergics. Following one month on this regimen, they were given a course of feedback training consisting of ten 14-minute sessions. Group one participants were provided with a tone contingent upon oral-lingual movements above a yoked threshold. Group two participants were given noncontingent feedback tones generated randomly. Weekly AIMS were administered as well as an initial baseline during each session to determine current level of oral-lingual activity. An analysis of session effects indicated significantly more suppression of oral-lingual activity in the contingent group versus the noncontingent feedback group. Jaw and forehead activity also measured showed reductions of similar magnitudes for both groups.This work was sponsored in part by a Research Advisory Grant from the Department of Veterans Affairs awarded to Joanne Intrator. We gratefully acknowledge the valuable contributions of K. Duvvi, S. Kemble, and L. Kolman.     

Successful treatment of one case of tardive dyskinesia with electromyographic feedback from the masseter muscle

Evidence from one case with a 15-month follow-up is presented to support the conclusion that electromyographic (EMG) feedback from the masseter was effective in controlling tardive dyskinesia, while a combination of EMG feedback from the frontalis and verbal muscle relaxation training were not.     

The effects of practice and visual feedback on mandibular border movements

Twenty healthy subjects were studied on the effects of training on mandibular border movements. Maximum left (LL) and right (RL) lateral excursions, maximum protrusive movement (PT), maximum mouth opening (MO), the difference between left and right excursions (R-L), midline deflection (DF) during opening and closing and midline deviation of the jaw (MOD) at maximum opening position of mandibular border tracing with or without practicing and visual feedback were compared among various sessions. No significant difference has been found on the amount of border extension under the influence of training. However, 70 to 85% of the subjects had some improvement after verbal instruction practicing, while only 50 to 65% of the same subjects showed improvement through visual feedback. It is suggested that doing research related to the jaw border movement on healthy subjects does not have to train them to obtain comparable data. On the other hand, since repeated border tracing in healthy subjects did not worsen the results, practicing or visual feedback training might ascertain a repeatable border tracing.     

Effect of Withania somnifera glycowithanolides on a rat model of tardive dyskinesia.

Withania somnifera glycowithanolides (WSG) were investigated for their preventive effect on the animal model of tardive dyskinesia (TD), induced by once daily administration of the neuroleptic, haloperidol (1.5 mg/kg, i.p.), for 28 days. Involuntary orofacial movements (chewing movements, tongue protusion and buccal tremors) were assessed as TD parameters. WSG (100 and 200 mg, p.o.), administered concomitantly with haloperidol for 28 days, inhibited the induction of the neuroleptic TD. Haloperidol-induced TD was also attenuated by the antioxidant, vitamin E (400 and 800 mg/kg, p.o.), but remained unaffected by the GABA-mimetic antiepileptic agent, sodium valproate (200 and 400 mg/kg, p.o.), both agents being administered for 28 days like WSG. The results indicate that the reported antioxidant effect of WSG, rather than its GABA-mimetic action, may be responsible for the prevention of haloperidol-induced TD.     

The effects of EMG feedback training during problem solving

The present case study investigated the effects of competing task demands on biofeedback training to reduce frontalis muscle tension. Baseline levels of frontalis muscle tension were recorded for relaxation and problem solving. The subject was trained to decrease muscle tension with biofeedback for the problem-solving task alone. The results indicated that EMG training during problem solving was successfully accomplished. Frontalis muscle tension during relaxation baseline did not change as a result of reductions in muscle tension during problem-solving feedback training. This suggests that the decrease of muscle tension cannot be attributed to reductions in overall muscle tension levels. Instead, training was specific to the problem-solving feedback phases. Additionally, it was found that accuracy in problem-solving did not decline as a result of simultaneous feedback training. Thus EMG biofeedback training can be accomplished and exercised without disruption of ongoing mental activity.     

The effects of indomethacin and prostaglandin E2 on the ethanol-induced suppression of ovine fetal breathing movements.

A study was performed to examine the role of prostaglandins (PGs) in the mechanism of the ethanol-induced suppression of FBM, in which the objective was to test the hypothesis that fetal administration of PGE2 can suppress the incidence of FBM following reversal of ethanol-induced suppression of FBM by indomethacin, a fatty acid cyclooxygenase inhibitor. Instrumented near-term pregnant ewes received 1-h maternal infusion of ethanol (1 g/kg maternal body weight) followed 0.5 h later by a 3-h fetal infusion of indomethacin (1 mg/kg fetal body weight/h), and then a 2-h fetal infusion of PGE2 (400 ng/kg fetal body weight/min). Prior to drug administration, FBM occurred approximately 36.1 +/- 2.6% of the time. FBM were suppressed during the period of ethanol infusion (9.6 +/- 1.7%); the ethanol-induced suppression of FBM was reversed by fetal indomethacin treatment (77.5 +/- 14.1%); shortly after the onset of fetal PGE2 infusion, the incidence of FBM decreased to a 2-h mean incidence of 14.1 +/- 4.2%, which was similar in magnitude to that observed after maternal ethanol infusion. After the completion of PGE2 infusion, the incidence of FBM rapidly increased to a peak incidence of 83.4 +/- 19.2%, which was indicative of a prolonged effect of indomethacin on FBM. The data indicate that PGs mediate the ethanol-induced suppression of ovine FBM and that the action of indomethacin to antagonize ethanol-induced suppression of FBM is primarily due to its inhibition of PG synthesis.     

Use of gamma-linolenic acid in the treatment of schizophrenia and tardive dyskinesia.

There is good background evidence to suggest that essential fatty acids and their eicosanoid derivatives may play a role in schizophrenia and in with tardive dyskinesia. Trials involving treatment with essential fatty acids, or eicosanoids or drugs which stimulate eicosanoid synthesis have shown modestly promising results. Particularly favourable outcomes in both schizophrenia and tardive dyskinesia were associated with combined treatment using essential fatty acids and nutritional supplements.     

Peripheral-type benzodiazepine-binding sites in platelets of schizophrenics with and without tardive dyskinesia

The density of peripheral-type benzodiazepine (BZ)-binding sites was studied in platelets of 10 medicated chronic schizophrenics with tardive dyskinesia (TD), 10 medicated chronic schizophrenics without TD, 7 drug-free schizophrenics, and 10 normal controls. The age range of the study population was 36-60 years. Age and sex distribution were similar in all 4 groups. The unmedicated schizophrenics did not differ in their maximal binding capacity from the healthy controls. A significant decrease in the density of peripheral-type BZ-binding sites in platelets was observed in treated schizophrenics both with and without TD in comparison to controls and untreated schizophrenics. The reduction in [3H]PK 11195 binding was more pronounced in TD patients (31.3% of controls) than in patients without TD (21.1% of controls). However, this parameter failed to discriminate statistically between TD and non-TD medicated schizophrenics.     

Clinical and electromyographic effects of biofeedback training in mandibular dysfunction

Twenty patients with mandibular dysfunction, 10 acute and 10 chronic, were trained with electromyographic biofeedback from either m. masseter or m. frontalis area. The electromyographic activity in both muscle areas were recorded during six training sessions. The mean electromyographic activity decreased significantly within the sessions for both muscle areas, progressively more often for the m. masseter area. The activity did not decrease significantly between sessions for any muscle area. The clinical and subjective symptoms of mandibular dysfunction improved significantly after the training. No differences, electromyographically or clinically, among acute, chronic, m. masseter area, or m. frontalis area feedback patients could be observed. No correlation between decrease in electromyographic activity and symptoms could be established. Since a simplistic neuromuscular learning model for biofeedback training gains little support from these results, alternative views are discussed.This research was supported by grants to Sven G. Carlsson and Elliot N. Gale from the Swedish Council for Research in the Humanities and Social Sciences.     

Clinical and electromyographic effects of biofeedback training in mandibular dysfunction

Twenty patients with mandibular dysfunction, 10 acute and 10 chronic, were trained with electromyographic biofeedback from either m. masseter or m. frontalis area. The electromyographic activity in both muscle areas were recorded during six training sessions. The mean electromyographic activity decreased significantly within the sessions for both muscle areas, progressively more often for the m. masseter area. The activity did not decrease significantly between sessions for any muscle area. The clinical and subjective symptoms of mandibular dysfunction improved significantly after the training. No differences, electromyographically or clinically, among acute, chronic, m. masseter area, or m. frontalis area feedback patients could be observed. No correlation between decrease in electromyographic activity and symptoms could be established. Since a simplistic neuromuscular learning model for biofeedback training gains little support from these results, alternative views are discussed.     

The effects of EMG feedback training during problem solving: a case study.

The present case study investigated the effects of competing task demands on biofeedback training to reduce frontalis muscle tension. Baseline levels of frontalis muscle tension were recorded for relaxation and problem solving. The subject was trained to decrease muscle tension with biofeedback for the problem-solving task alone. The results indicated that EMG training during problem-solving was successfully accomplished. Frontalis muscle tension during relaxation baseline did not change as a result of reductions in muscle tension during problem-solving feedback training. This suggests that the decrease of muscle tension cannot be attributed to reductions in overall muscle tension levels. Instead, training was specific to the problem-solving feedback phases. Additionally, it was found that accuracy in problem-solving did not decline as a result of simultaneous feedback training. Thus EMG biofeedback training can be accomplished and exercised without disruption of ongoing mental activity.     

Effect of Emblica officinalis tannoids on a rat model of tardive dyskinesia

Effect of active tannoid principles of E. officinalis, comprising of emblicanin A (37%), emblicanin B (33%), punigluconin (12%) and pedunculagin (14%), was investigated on a rat model of tardive dyskinesia (TD) induced by once daily administration of haloperidol (1.5 mg/kg, ip) for 28 days. Involuntary orofacial movements (chewing movements, buccal tremors and tongue protusion) were assessed as TD parameters. The tannoid principles of E. officinalis (EOT) were administered concomitantly with haloperidol in the doses of 10, 20 and 50 mg/kg, po, for 28 days. Sodium valproate (200 mg/kg, po), a Gaba-mimetic agent, and vitamin E (400 mg/kg, po), an antioxidant, were used as the standard drugs and administered for the same period. EOT induced a dose-related inhibition of all the three TD parameters assessed, as did vitamin E. The effect of sodium valproate remained statistically insignificant. The results suggest that EOT exerts a prophylactive effect against neuroleptic-induced TD which is likely to be due to its earlier reported antioxidant effects in rat brain areas, including striatum.     

A comparison of direct blood pressure feedback and electromyographic feedback on the blood pressure of normotensives

Groups of 20 normotensive subjects were assigned to one of three conditions to help them lower their blood pressure: (1) intermittent visual feedback of blood pressure; (2) continuous analogue auditory feedback of frontal EMG; (3) an instructed, no-feedback condition. Both groups receiving feedback showed greater within-session lowering of systolic blood pressure than the no-feedback control group. Although the group receiving intermittent visual feedback of blood pressure lowered blood pressure more than the EMG feedback group at the first session, in three subsequent sessions, the two feedback groups did not differ.     

The effects of unsupervised movement training with visual feedback on upper limb kinematic in persons with shoulder impingement syndrome

Persons with shoulder impingement syndrome (SIS) present impairments that can be improved following supervised movement training with feedback; however, retention is low. The purpose of this study was to evaluate if kinematic changes observed following supervised training can be maintained using unsupervised training with visual feedback. Thirty-three subjects with SIS participated in two visits, one day apart. Kinematic patterns of the upper limb were evaluated once during the first visit, immediately after supervised training; they were evaluated twice during the second visit, before and immediately after unsupervised training. Kinematic patterns were characterized by total excursion and final position during reaching. Unsupervised training consisted of reaching movements performed in front of a mirror. The day after supervised training, subjects with SIS used significantly larger trunk rotation and finished reaching with the trunk more rotated as compared to immediately after supervised training. Following unsupervised training, kinematics of the trunk was back to the level observed immediately after supervised training. Subjects who presented the largest kinematic deficits also significantly improved their shoulder and clavicular movements. Unsupervised training appears to be a good complement to supervised training in order to normalize the kinematic impairments of persons with SIS as compared to healthy subjects.     

The role of kinaesthetic feedback in goal-directed movements

The purpose of this study was to investigate the role of kinaesthetic feedback in the control of goal-directed movements. The subjects were qualified basketball and handball players compared to weightlifters as controls. The body measures and the general motor tests verified fit physical condition of the subjects, and detected no sign that would disturb the execution of special motor tests. The special motor tests were free-throw shootings with basketball to the basket, free shootings with handball to a rectangular frame, zigzag dribbling with basketball to 14 m among traffic cones 2 m apart, and stopping at a mark after running to 10 m. These tests were performed both with open eyes and closed eyes. The results of all special motor tests decreased significantly in the lack of visual information. Furthermore, in contrast to the significantly different results obtained from the three different groups with open eyes, these groups produced equally minor results with closed eyes. It is concluded that the practice of goal-directed movement, learned under visual guidance, does not make the kinaesthetic feedback able to compensate the lack of visual input.