Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Contingent Negative Variation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23Linked to original sources
PubMed2005

5 Hz repetitive TMS increases anticipatory motor activity in the human cortex.

In the present study, we analyzed how high-frequency repetitive transcranial magnetic stimulation (rTMS) of the primary motor hand area (M1-Hand) shapes anticipatory motor activity in frontal areas as indexed by the contingent negative variation (CNV). Eight right-handed volunteers received real or sham 5Hz rTMS at an intensity of 90% resting motor threshold (1,500 stimuli per session). Real but not sham rTMS to left M1-Hand induced a site-specific increase in amplitude of the late component of the CNV at the electrode C3 overlaying the site of stimulation. The increase in pre-movement activity in the stimulated cortex may reflect an increase in facilitatory drive from connected motor areas, enhanced responsiveness of the stimulated cortex to these inputs or both.

Adult↗
PubMed1992

Anterior brain electrical asymmetries in response to reward and punishment.

A variety of recent research indicates that when subjects are induced to experience certain negative emotions, there is greater suppression of alpha power in the right than left frontal region, while during the experience of positive emotion, alpha power asymmetry in this region shows the opposite pattern. We have conceptualized this asymmetry as reflecting specialization for approach and withdrawal processes in the left and right frontal regions, respectively. In this experiment, reward and punishment contingencies were directly manipulated to produce approach and withdrawal emotional states. In addition, subjects responded to imperative stimuli using either an approach response (finger press) or a withdrawal response (finger lift). EEG was recorded from multiple scalp locations. During the foreperiod prior to the response to the imperative stimuli, the EEG was extracted, Fourier-transformed and power computed in the theta, alpha and beta frequency bands. In addition, the contingent negative variation (CNV) was derived from the identical epoch. Reward trials were associated with greater left frontal alpha power suppression than punishment trials, while during the latter trials, there was greater right-sided frontal alpha power suppression than during reward trials. There was also some evidence to indicate that withdrawal responses were associated with greater right-sided alpha power suppression in the temporo-parietal region compared with approach responses. Power in the theta and beta bands did not systematically vary with condition. The CNV was larger during trials on which subjects responded quickly compared with slow trials, but did not differentiate between reward and punishment contingencies. The findings support the hypothesis that approach-related processes can be differentiated from withdrawal-related processes on the basis of asymmetrical shifts in alpha power in the frontal region. They also indicate that the CNV and spectral power estimates from the identical epochs reflect different neural processes.

Adolescent↗
PubMed2001

A medial to lateral shift in pre-movement cortical activity in hemi-Parkinson's disease.

OBJECTIVE: Recent evidence suggests that cortical activity associated with voluntary movement is relatively shifted from medial to lateral premotor areas in Parkinson's disease. This shift occurs bilaterally even for unilateral responses. It is not clear whether the shift in processing reflects an overall change in movement strategy, thereby involving alternate cortical areas, or reflects a compensatory change whereby, given the appropriate conditions, less impaired cortical areas are able to provide a similar function in compensation for those areas which are more impaired. This issue was examined in patients with hemi-Parkinson's disease, in whom basal ganglia impairment is most pronounced in one hemisphere. METHODS: Fourteen patients with hemi-Parkinson's disease and 15 age-matched control subjects performed a Go/NoGo finger movement task and the contingent negative variation (CNV) was recorded from 21 scalp positions. RESULTS AND CONCLUSIONS: Maximal CNV amplitudes were found over central medial regions for control subjects, but were shifted more frontally for Parkinson's disease patients, reduced in amplitude over the midline and lateralized towards the side ipsilateral to the greatest basal ganglia impairment. This shift in cortical activity from medial to lateral areas in Parkinson's disease patients appears to reflect a compensatory mechanism operating predominantly on the side of greatest basal ganglia impairment.

Action Potentials↗
PubMed1993

[The value of cognitive psychophysiological studies in a comprehensive approach to schizophrenia (treatment of information and attention capacities in acute-stage schizophrenia)].

According to information processing theory, attention deficits appear to be a nuclear disorder in schizophrenia which the study has been renewed with the development of neurophysiology technique. The originality of our research was to study in a same subject Event-Related-Potentials in three different conditions: passive and active auditory oddball paradigm for Mismatch Negativity (MMN) and P 300, and a simple reaction time task with warming stimulus for the Contingent Negative Variation (CNV). The study was carried out among 20 schizophrenic subjects (paranoid subtype with acute exacerbation, DSM-III-R) and 20 healthy volunteers. Patients differed from controls as the following: a lower amplitude of N1-P2 components of the auditive evoked potentials, a lower amplitude of MMN (absent in 20% of the psychotic subjects), a lower amplitude and a longer latency of P300, and a lower amplitude of CNV. These results suggest a fundamental dysfunction of information processing which involves the early stages of automatic and voluntary attentional cognitive processes in schizophrenia.

Adult↗
PubMed1994

Biological correlates of deliberate self-harm behaviour: a study of electroencephalographic, biochemical and psychological variables in parasuicide.

Clinical, electroencephalographic and biochemical variables were measured in 40 patients who attempted suicide and 27 age-matched controls. Patients had significantly higher scores for depression, hopelessness, neuroticism and psychoticism and lower scores for extraversion than controls. They also had significantly lower contingent negative variation (CNV), higher postimperative negative variation and lower whole blood serotonin values than controls. Within the patient group, vulnerability to parasuicide, as determined by previous or repeated acts of deliberate self-harm, was associated with higher scores for hopelessness and suicide intent, lower scores for extraversion and decreased CNV. Factor analysis revealed significant correlations between psychological variables and auditory evoked potential amplitudes for the vulnerable group. A profile of variables associated with increased risk of self-harm in patients presenting with attempted suicide is proposed from our data.

Adolescent↗
PubMed1978

The timing of CNV resolution in a memory retrieval task.

Twelve men performed the Sternberg memory retrieval task while the EEG and EOG were recorded. Subjects saw a target set of 1 to 4 digits followed by a warning tone that was followed after 1.5 sec by a probe digit. Subjects indicated by pressing one of two levers whether the probe digit was in or out of the target set. The timing of contingent negative variation (CNV) resolution was measured as the latency of 50% resolution in stimulus-synchronized waveforms (SSWs), response-synchronized waveforms (RSWs), and model waveforms (MWs). The MWs were constructed by adding each RSW to itself using time displacements derived from the reaction times of the single trials of which the RSW was an average. The results indicated that CNV resolution is related to the timing of the motor response. MWs had resolution latencies close to those of the SSWs. In SSWs the N1 and P3 to the warning tone also varied with target set size.

Adolescent↗
PubMed1986

Beta blockers and the central nervous system.

The exact mechanism of action of beta blockers in migraine remains undetermined. An effect on the central nervous system (CNS) might be a factor. The evidence from the literature indicates that the anatomical and chemical targets for these drugs are present in the mammalian brain, that they readily penetrate the brain, and that they may modify CNS functions. The present study shows that psychomotor tests and contingent negative variation (CNV), an event related slow cerebral potential, both of which are abnormal in untreated migraineurs, tend to normalize after treatment with the beta blocker metoprolol. Moreover, a strong positive correlation was found between the amplitude of CNV and the clinical efficacy of beta blockers in migraineurs. One might hypothesize that a hyperactive central catecholaminergic state in migraine might be the common denominator between reduced performance on psychomotor testing and enhanced CNV. It remains to be determined whether this is due to hyperactivity of catecholaminergic neurons or to hypersensitivity of catecholamine receptors.

Adrenergic beta-Antagonists↗
PubMed1976

Relationship between central and autonomic nervous system activity: correlates of psychomotor performance in elderly men.

The relationship between heart rate deceleration (HRD) and the contingent negative variation (CNV) was evaluated in 12 healthy, elderly men during performance of a signaled reaction time task. While amplitude of the CNV and HRD did parallel RT, CNV alone was found to be predictive of individual differences in speed of response indicating that phasic concordance of these physiological responses is probably not an important factor in age changes in RT. The results indicate the probable importance of central physiological indices such as the CNV over peripheral events such as HRD in the evaluation of RT performance in elderly individuals.

Aged↗
PubMed2003

Processes involved in tempo perception: a CNV analysis.

The purpose of this research was to study the mechanisms underlying tempo perception, by looking at their electrophysiological brain correlates. The subjects' task consisted of comparing the tempos of two isochronous tone sequences made up of either three (condition 13) or six (condition 16) 600-ms intervals. Contingent negative variation (CNV), known to be linked to the judgment of a single interval, kept increasing in amplitude for three intervals during tempo encoding, thereby providing evidence of the occurrence of CNVs also for several intervals in succession. This CNV increase could reflect the use of interval-based processes in the building of the interval memory trace. During the comparison phase, a CNV decrease was observed in condition 16, suggesting that subjects did not build a new memory trace, but used beat-based processes to check whether the beats of the new tempo occurred at the times they anticipated.

Acoustic Stimulation↗
PubMed1999

Reactivity and event-related potentials during attentional tests in athletes.

A series of attentional tests involving reaction times (RTs) was administered to 12 high-level young (age 17-18 years) volleyball players. During the tests, event-related potentials were recorded by electroencephalogram. In a simple reaction-time test (SRT), the subjects had to respond to a letter that appeared on a white screen. Other tests (attentional shifting tests) consisted of a go/no-go reaction time and a choice reaction time (CRT), divided into a short-latency CRT and a long-latency CRT. In the pre-stimulus period of these tests, there is a shift from broad attention to selective attention, represented by a crowding of black points on the computer screen, followed by the appearance of a letter in the centre of the crowding. The results show that RT increased from SRT to CRT. In the attentional shifting tests, averaged waves of event-related potentials showed a contingent-negative-variation-like wave that was closely related to selective attention (selective attention wave, SAW) before the onset of the stimulus. After the stimulus, a P3 complex was recorded. Correlations were found between the SAW amplitude and P3 latency and amplitude, and between these parameters and RT and its variability. Higher SAW and P3 amplitudes were accompanied by a shorter RT and a lower variability. The characteristics and the correlations that exist between the various parameters are consistent with a possible use of these tests in the analysis of the attentional styles of athletes, and in the evaluation of their progress with training.

Adolescent↗
PubMed2004

Attentional distraction of CNV depending on the spatial focus.

To investigate the distraction of spatial attention to the task-irrelevant visual stimuli, contingent negative variation (CNV) was measured by using a forewarned reaction time task in 20 healthy subjects. The lasting emission of light, irrelevant to the CNV task, at each perimetric angle of 15 degrees, 30 degrees or 45 degrees to the fixated point was presented to the subjects. The amplitude of early CNV was small only under the light-emission at the angle of 30 degrees. Our results indicate that attention is distracted even by the lasting, task-irrelevant stimuli and that distraction is dependent on the focusing function of attention.

Adolescent↗
PubMed1989

CNV abnormalities following closed head injury.

Event-related potentials (ERPs) were recorded in a GO/NO-GO reaction time task from 20 closed head injury patients, at least 6 months postinjury, and from 20 controls. In this task the pitch of an initial tone (Sl) indicated whether or not a response was required to a second tone (S2) occurring 1.5 s later. In the control group both the early, frontal-maximum, and the later vertex-maximum, components of the contingent negative variation (CNV) were larger on GO than NO-GO trials. In the patients, the early frontal CNV wave did not differentiate GO and NO-GO trials, and the late CNV showed a smaller separation between these trial types than did the late CNV of the control group. These CNV abnormalities may reflect impairments in selectively orienting to salient stimuli, and in differential response preparation. Such impairments might in turn reflect the damage to the frontal lobes and/or their connections that commonly occurs as a result of closed head injury.

Acoustic Stimulation↗
PubMed2005

Relationship between CNV and timing of an upcoming event.

This study reports an analysis of the Contingent Negative Variation (CNV) recorded on the human scalp during the comparison of a test duration with a previously memorized duration. Results show that CNV activity peaks at the end of the memorized duration, and that its slope varies inversely with the length of this duration. These features of CNV activity are similar to those of climbing neuronal activity observed through intracerebral recordings in animals, and suggest that both activities reflect how the brain encodes the timing of an upcoming event. These results also show that the time-course of the CNV in timing tasks is compatible with a pacemaker-accumulator model of temporal processing.

Acoustic Stimulation↗
PubMed1979

Methadone effects on brain functioning and type A and B CNV shapes.

Twelve male outpatients participating in a methadone maintenance treatment program were evaluated for the effects of acute administration of methadone on brain functioning (contingent negative variation or CNV), attention performance (reaction time and continuous performance test), and psychophysiological activity (heart rate and eye blink rate). Individual differences in response to methadone were assessed by classifying patients into two groups on the basis of basal CNV shapes: Type A (quick rise time) and type B (slow rise time). Methadone produced a pattern of increased electrical brain activity (CNV) and enhanced attention performance in type B patients and elevated heart rate and lowered eye blink rate in type A subjects. Results are interpreted in terms of the distraction-arousal and the eye blink-hedonia hypotheses.

Adult↗
PubMed1981

[Infusion test in the normal pressure hydrocephalus (author's transl)].

Continuous monitoring of the intracranial pressure and ventricular infusion test were carried out in 13 cases in which normal pressure hydrocephalus (NPH) was suspected. The infusion test was performed by intraventricular bolus injection of 8 ml of saline. The result was collated with the effect of shunting operation, which was judged by means of the improvement in the clinical symptoms and the amplitude of contingent negative variation. The excellent effect of shunting operation was obtained in the patients who showed the T of more than 200 sec, the compliance of less than 1.0 ml/mmHg, the conductance to outflow of less than 0.8 ml/mmHg/min and CSF outflow resistance of more than 15 mmHg/ml/min. In 3 cases out of the 5 effective cases, A or B wave was seen. However, appreciable variation of the values was shown among the cases so that it was concluded that the all-round-consideration must be done to select the case for the shunting operation with the findings in RI-cisternography, pneumoencephalography, computerized tomography and so on. This fact might indicate the existence of the complicated pathophysiology in NPH resulted from not only the impairment of cerebrospinal fluid circulation but also the disturbance of cerebral blood flow, changes in plasticity of the brain and so on.

Adult↗
PubMedDate not supplied

Preprogramming motor dysfunction in paroxysmal kinesigenic choreoathetosis.

Paroxysmal kinesigenic choreoathetosis (PKC) is characterized by abnormal involuntary movements precipitated by sudden movement. As a result, a possible impairment of cerebral organization of voluntary motor activity is hypothesized in PKC. We examined a 14-year-old boy affected by a sporadic form of PKC, adopting a multimodal psychophysiological approach, including P300, contingent negative variation (CNV) and a specific paradigm for the study of movement related potentials (MRPs). Recordings were made before and after phenobarbital therapy. No changes were observed in the non-motor parameters (P300 and early wave of the CNV), whereas the premotor CNV component and the electrophysiological components, reflecting the preprogramming activity of a voluntary motor act, showed selective modifications induced by the anticonvulsant therapy. Our PKC patient presents a disorder of temporal organization of a voluntary motor response to a stimulus. Both a clinical improvement and normalization of motor-related electrophysiological anomalies were observed during phenobarbital (PB) therapy.

Adolescent↗
PubMed2006

Relationship between precipitating agents and neurophysiological abnormalities in migraine.

The particular mechanisms of migraine anticipation by different precipitating agents are still unknown. The contingent negative variation (CNV) was recorded in the premenstrual and ovulation phases of the cycle in both rest and stress conditions in 17 migraine and 15 healthy women. In migraineurs a significant increase of amplitude of the initial CNV component in the premenstrual phase compared with ovulation was observed. During both the ovulation and premenstrual phases both migraineurs and controls demonstrated a significant increase of the CNV amplitude on stress. The increase of the amplitude on stress in the premenstrual phase was more pronounced in migraineurs. This study shows that stress and menstrual cycle are associated with changes of the initial CNV amplitude, probably indicating a higher probability of migraine attacks.

Adult↗
PubMed1991

Multimodality exploration of event-related potentials in chronic alcoholics.

Short- and long-latency auditory evoked potentials (SAEPs and LAEPs), visual-evoked potentials (VEPs), and contingent negative variation (CNV) were studied in 32 chronic alcoholics and their age-, sex-, and education-matched control subjects. The alcoholics exhibited a delayed SAEP peak V and an increase in the III-V and I-V intervals, increased VEP P100 latency, increased LAEP N2 and P3 latencies and increased LAEP N1-P2 amplitude. The analysis of the anomalies at a clinical level indicates a differential sensitivity of the event-related potentials. The parameters most sensitive to chronic alcohol consumption were (in descending order) P3 latency, peak V latency, the I-V and III-V intervals, and P100 latency.

Adult↗