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Results for “Contingent Negative Variation”

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PubMed1988

Inhibitory influence of oxytocin infusion on contingent negative variation and some memory tasks in normal men.

A double-blind study combining electrophysiological and psychometrical approaches was carried out to investigate the central effects of an intravenous oxytocin (OT) infusion in normal men. Contingent negative variation (CNV) was selected as the measure of central cognitive evoked potential, and the psychometric tests measured mood, vigilance and memory. OT infusion induced a significant decrease of CNV amplitude and an increase of post-imperative positive potentials in vertex derivations. A similar effect was still evidenced one week after treatment in frontal derivations, suggesting a long time effect of OT on human brain. No significant influence of OT on mood or vigilance tests was apparent; only one item of a memory test revealed a significant impairment of some mnesic performances. These observations provide new electrophysiological arguments supporting a central action of peripheral OT administration in man.

Adult↗
PubMed1978

Contingent negative variation and alpha attenuation responses in children with different abilities to concentrate.

In three paralleled groups, each of seven children (age, 11 years) with reliable high, average and low ability to concentrate, measured by psychological tests, the contingent negative variation (CNV) and the concomitant alpha attenuation responses were studied in warned reaction time experiments. Stimuli were tone (S1) and patterned light (S2). In half of the trials, S2 was a square, in the other half a triagle, stimuli being projected in random order onto the fixation point. In two experiments the children had to react (a) to each type of S2, and (b) selectively to one type of S2. Significant group differences were found. In comparison to the children with low ability to concentrate, the children with average and especially those with high ability to concentrate showed: (1) stronger central occipital alpha attenuation responses to the warning stimulus, but no differences in the early CNVs; (2) more occipital alpha reduction and enhanced development of central negativity before the imperative stimulus; (3) task-specific modulation of these responses, i.e. larger pre-S2 rise in negativity in the simple reaction task, and stronger pre-S2 reduction of alpha amplitudes in the discriminative reaction task.

Alpha Rhythm↗
PubMed1975

[Basis and clinical application of the "contingent negative variation" in "evoked response audiometry" (author's transl)].

After repeated stimulation with an indicative stimulus and a second imperative stimulus, a slow negative potential shife, the "Contingent Negative Variation" (CNV), can be recorded in the EEG before the second stimulus. On account of the main features of CNV two qualitative tests can be used in audiometry. "Tone-CNV" is an objective test of perception of a pure-tone. The indicative pure-tone is followed regularly by a second imperative stimulus, a flash of light or a slide. The appearance of CNV is the positive sign of perception, even if the "acoustically evoked potential" (AEP) is difficult to define. Adults and children (5 to 12 years) with normal hearing or suffering from several forms of hearing loss developed a CNV, except those patients with severe brain damage. The advantage of this method is the short testing time and accentuation of AEPs. The test can be also done under sedation. In "Objective Speech Audiometry", a proof of concept discrimination, only words of one concept are combined with a second imperative stimulus. The other group of words of the second concept remains "unreinforced". After correct discrimination all normal subjects developed a CNV before the second stimulus and after the "unreinforced" concept a "Discriminative Positive Variation" (DPV). Thus, this method can be used for clinical purposes. Loss of discrimination, perseveration phenomena and hemispheric differences were observed in aphasic patients.

Acoustic Stimulation↗
PubMed1977

[The importance of the "contingent negative variation" (CNV) for audiometry (author's transl)].

Previous proofs of "central processes" in hearing were based on the determination of the late "auditory evoked potentials" (AEP's: 50--300 ms) in EEG. The appearance of AEP's in different sleep stages raises the question, if the AEP actually conscious hearing. Since the discovery of the "Contingent Negative Variation" (CNV), as a potential depending on conscious and cognitive factors, an appropriate "instrument" is available to solve this problem. Using the CNV-technique three proofs of central auditory perception are described and discussed: a) "The objective proof of the perception of pure-tones", useful for threshold determination, test in the case of simulation and central hearing disorders. b) "The objective proof of the perception of stimulus-changes", useful for exact determination of differential thresholds for frequencies or intensities. c) "The objective speech audiometry", proof of speech comprehension, useful in case of aphasia and simulation.

Auditory Perception↗
PubMed1990

Relationships between N1, P300, and contingent negative variation recorded at age 15 and criminal behavior at age 24.

Recent event-related potential (ERP) studies indicate that antisocial and psychopathic behavior is in some circumstances characterized by heightened attentional processes. This prospective study assesses whether ERP measures of attention recorded in adolescence are capable of predicting criminality status in adulthood. N1, P300, and contingent negative variation (CNV) were recorded during a CNV paradigm in a representative sample of 101 male schoolchildren at age 15, and related to criminality status at age 24. Criminals-to-be were characterized by larger N1 amplitudes and faster P300 latencies to the warning stimulus. Psychopathic personality within the criminal group was associated with larger N1 and CNV amplitudes. A discriminant function analysis using N1 and P300 measures correctly classified 74% of cases. It is concluded that enhanced early attentional processing may be of etiological significance in the development of criminality and that ERP measures may be of value in the early prediction of criminal behavior.

Adolescent↗
PubMed1975

The contingent negative variation during a memory retrieval task.

Evoked potentials were recorded from the human scalp during performance of a memory retrieval task modeled after a paradigm originated by Sternberg (1966). Subjects were required to decide whether a probe digit was contained in a series of one to four target digits presented a few seconds before. The amplitude of the contingent negative variation (CNV) preceding the probe digit and the speed of CNV resolution after the probe varied as a function of target set size. CNV amplitude was greatest when the set size was one. The smaller the set size, the more positive the evoked potential 300 msec after the probe, regardless of whether a motor response was required.

Adult↗
PubMed1975

Effects of warning-signal duration on the early and late components of the contingent negative variation.

Slow EEG potentials were recorded from three sites on the scalp (Fz, Cz and Pz) during a simple reaction time task in which the duration of the warning signal was either 0.5 or 2 sec. The duration of the foreperiod was held constant, and order of conditions was varied according to a latin square design. As predicted, the longer warning signal evoked increased amplitude of the early component of the contingent negative variation (CNV). These results confirm the interpretation of that wave as an orienting response. In contrast, the duration of the warning signal did not affect the second CNV component or reaction time latency. Additional dissociation between the two CNV components was evident in their distribution on the scalp. The early component was smallest at Pz, whereas the late component attained its lowest amplitude at Fz. Concurrently recorded palmar skin potentials exhibited different polarity and latency from the CNV.

Acoustic Stimulation↗
PubMed1988

[Relationship between dexamethasone suppression test and contingent negative variation in major depressive patients].

We tried to relate two different indexes sensitive to the perturbations induced by major depression: the Dexamethasone Suppression Test or DST (Caroll, 1982) and the Contingent Negative Variation (CNV). The question was whether abnormalities in cortisol levels, following dexamethasone would enlight the modifications observed in CNV parameters and other electrophysiological indexes (EEG spectrum, reaction time). In 61 major depressive patients, 29 being DST-non-suppressors, we calculated differences in electrophysiological variables according to DST suppression or not, but we were not able to evidence significant differences between the groups. However, there were correlations between log-transformed levels of cortisol and on the one hand, CNV slope (r = -0.34, P less than 0.03) and on the other hand, reaction time (r = 0.45, P less than 0.01). Correlations between electrophysiological variables appeared in the sole suppressors group (e.g. CNV amplitude and alpha rythm reactivity; post-imperative variation and percent beta of the EEG spectrum). These results underline the complementary aspect of the two methods.

Adult↗
PubMed1991

Comparison of adinazolam, amitriptyline, and diazepam in endogenous depressive inpatients exhibiting DST nonsuppression or abnormal contingent negative variation.

Adinazolam, a triazolobenzodiazepine that has an action similar to antidepressants in several pharmacological tests, was compared with amitriptyline and diazepam in endogenous depressive inpatients exhibiting dexamethasone suppression test non-suppression and/or abnormal contingent negative variation. Three parallel groups of 22 patients received in double-blind conditions either adinazolam (60-90 mg/day), amitriptyline (150-225 mg/day), or diazepam (30-45 mg/day) over a 4-week period, with weekly assessments by the Hamilton Rating Scale for Depression. Results showed significant superiority of amitriptyline over diazepam on total Hamilton depression scores. On the endogenomorphy subscale, amitriptyline induced significantly better improvement than both diazepam and adinazolam, whereas both amitriptyline and adinazolam exhibited significantly better antidepressant efficacy on the core symptoms of depression. Moreover, the dropout rate for inefficacy after 2 weeks of treatment was higher in the diazepam group. Taken together, these findings suggest that adinazolam has an antidepressant efficacy intermediate between amitriptyline and diazepam. Adinazolam was, however, much better tolerated than amitriptyline, and produced significantly fewer anticholinergic side effects.

Adult↗
PubMed1987

Contingent negative variation and reaction time in patients with presenile idiopathic cognitive decline and presenile Alzheimer-type dementia. Preliminary report on long-term nicergoline treatment.

Up to date 6 patients with initial presenile idiopathic cognitive decline (PICD) and 5 suffering from a presenile Alzheimer-type dementia (PAD) with a mean age of 59.5 were admitted to the trial. The 6 PICD patients were assigned to a double-blind nicergoline/placebo 6-month course with an oral dose of 30 mg twice a day. PAD patients were treated in an open design (nicergoline oral dose 30 mg twice a day) for at least 6 months. Until now only 4 PICD and 3 PAD patients have been treated regularly for 6 months. Two of 4 PICD patients showed a progressive enhancement of contingent negative variation (CNV), shorter reaction time (RT) and an improvement of clinical status. The other 2 PICD patients, on the contrary, showed a progressive mild worsening of CNV-RT and clinical patterns. The double-blind trial is not yet completed. CNV activity, RTs and clinical patterns progressively improved also in 2 PAD patients while in the 3rd they remained nearly unchanged or minimally worse during the 6-month treatment. The positive nicergoline effect on CNV-RT and clinical status noted in our patients appeared similar to that observed by other authors with DHEMT in patients with senile dementia of Alzheimer type. No adverse drug-related reactions were seen.

Alzheimer Disease↗