[Electroencephalographic and psychogalvanic changes in the word-motor conditioning test].
Explore the source record for details and available documents.
Electroencephalography↗
SEARCH · PubMed Health
Results for “REFLEX, PSYCHOGALVANIC”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Startle responses in hereditary hyperekplexia.
BACKGROUND: Patients with hereditary hyperekplexia have excessive startle responses that are accompanied by transient stiffness and also continuous stiffness in infancy. A point of mutation has been identified for the major form of hereditary hyperekplexia in the gene encoding the alpha 1 subunit of the glycine receptor. OBJECTIVE: To measure startle reflexes and autonomic responses in the major form of hereditary hyperekplexia in the original Dutch pedigree. DESIGN: Startle reflexes and autonomic responses were examined by administering 3 series of 20 auditory stimuli at intervals of 10 seconds (90 and 113 dB) and 60 seconds (113 dB). SETTING: The Department of Neurology and Clinical Neurophysiology at the Leiden University Hospital, Leiden, the Netherlands. SUBJECTS: Nine patients with the major form of hyperekplexia and 20 healthy controls. Of the 9 patients, 5 took medication. The patients are part of the Dutch hyperekplexia pedigree. MAIN OUTCOME MEASURES: Startle responses were quantified with latency periods and areas of electromyographic bursts of the orbicular muscle of the eye, sternocleidomastoid and biceps muscles, and the thenar muscles. Autonomic reactions were measured with psychogalvanic responses and beat to beat changes of blood pressure and heart rate. RESULTS: The electromyographic bursts of the 4 muscles occurred in similar order in both patients and controls. The onset of the latency periods in the patient group was significantly (P < .001) prolonged in patients who took medication. Without medication, patients had shorter latency periods of the sternocleidomastoid muscle (P = .003) than controls. The electromyographic burst occurred significantly more often in patients than in controls (P < .001). The areas of the bursts were significantly larger in patients than in controls (P < .001); the degree of habituation was significantly stronger in patients than in controls (P < .001). The amplitude of the psychogalvanic response was increased in hyperekplexia, and the degree of habituation was significantly weaker in patients than in controls. Blood pressure and heart rate did not clearly react in either group. CONCLUSIONS: Motor startle responses are stronger and show more habituation in patients with hereditary hyperekplexia than in controls. The excessive responses include the psychogalvanic response. Increased responses do not necessarily indicate decreased habituation in hyperekplexia.
Acoustic Stimulation↗
The startle pattern in the minor form of hyperekplexia.
BACKGROUND: The major and minor forms of hereditary hyperekplexia (HE) are characterized by excessive startle responses, which are accompanied by transient stiffness only in major HE; patients with major HE also have continuous stiffness during infancy. A point mutation has been identified for major HE in the gene encoding the alpha 1 subunit of the glycine receptor but not for minor HE. OBJECTIVE: To measure startle reflexes and autonomic responses in the major and minor forms of HE in the original Dutch HE pedigree. DESIGN: Startle reflexes and autonomic responses were studied with 3 series of 20 auditory stimuli with intervals of 10 seconds (at 90 and 113 dB) and 60 seconds (at 113 dB). SETTING: A university hospital neurologic department. PATIENTS: Four patients with minor and 9 patients with major HE (patient groups) (a part of the Dutch HE family pedigree) and 20 healthy controls (control group). MAIN OUTCOME MEASURES: Startle movements were quantified with latencies and areas of electromyographic bursts of the following 4 muscles: the orbicular muscle of the eye, the sternocleidomastoid muscle, the biceps muscle of the arm, and thenar muscles. Autonomic reactions were measured with psychogalvanic responses. RESULTS. The 4 muscles contracted in similar order in the groups. The onset latencies of the orbicular muscle of the eye, the sternocleidomastoid muscle, and the biceps muscle of the arm were significantly prolonged in patients with minor HE (P < .006). The frequencies of occurrence of the electromyographic bursts were not different in the minor HE and major HE groups, but they were significantly higher in both patient groups compared with those in the control group (P < .001). The magnitude of the startle responses did not differ between the 2 patient groups (P = .4), but it was larger in both patient groups than in the control group (P < .001). Startle habituation in the minor HE group was much weaker than in the major HE group (P < .001) or in the control group (P < .001). The size of psychogalvanic responses (P = .1) and the degree of habituation (P = .24) in the minor HE group did not differ from those in the major HE group. Compared with that in the control group, the size of psychogalvanic responses in the minor HE group was larger (P < .001) and they habituated stronger (P < .001). CONCLUSIONS: The differences in the startle pattern between major HE and minor HE agree with the clinical and genetic findings: only major HE constitutes part of the HE phenotype. The cause of the minor HE is, as yet, unknown.
Adult↗