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 595 records · Page 33Linked to original sources
PubMed1986

Excessive daytime sleepiness and the pathophysiology of narcolepsy-cataplexy: a laboratory perspective.

The main disabling symptom of narcolepsy-cataplexy is shown to be the unrelenting excessive daytime sleepiness (EDS) based upon controlled studies of socioeconomic effects and the poor response to treatment. Objective performance deficits mainly involve tests of ability to sustain performance on repetitive boring tasks and are reversible by improved alertness. Physiologically, EDS is seen to represent relatively slow waxing and waning of alertness rather than punctate microsleeps. Evidence is provided for complex cerebral evoked potentials (P300, contingent negative variation) being very sensitive EDS measures comparable to the multiple sleep latency test (MSLT). EDS appears to have qualitatively somewhat different forms mainly reflecting pressure for REM sleep (REM sleepiness) or pressure for NREM sleep (NREM sleepiness), which have different effects on cerebral evoked potentials as well as subjective and objective (MSLT) differences. It is argued that in pathophysiological terms narcolepsy may best be considered a disease of state boundary control.

Cataplexy↗
PubMed2005

Electrophysiological evidence for lateralization of preparatory motor processes.

Event-related potentials were recorded during a warned choice reaction time task in which the warning signal was informative (it signaled the specific response to be required) or uninformative (it gave no response-specific information). The response signal specified a key press with either the middle or the ring finger of the left or the right hand. The informative warning signal facilitated reaction time in two separate protocols. The contingent negative variation elicited following the informative warning signal was larger than that following the uninformative warning signal, and this effect was larger over the left hemisphere than over the right hemisphere. This finding gives converging evidence that preparatory motor processes are predominantly lateralized to the dominant hemisphere.

Adult↗
PubMed2001

The pathophysiology of migraine.

BACKGROUND: Migraine results from episodic changes in central nervous system physiologic function in hyperexcitable brain manifested by abnormal energy metabolism, lowered threshold for phosphene generation, and increased contingent negative variation. Human functional magnetic resonance imaging and magnetoencepholography data strongly suggest that aura is caused by cortical spreading depression. REVIEW SUMMARY: Brain hyperexcitability may be caused by low magnesium levels, mitochondrial abnormalities with abnormal phosphorylation of adenosine 5'-diphosphate, a dysfunction related to nitric oxide, or calcium channelopathy. Low magnesium can result in opening of calcium channels, increased intracellular calcium, glutamate release, and increased extracellular potassium, which may in turn trigger cortical spreading depression. Mitochondrial dysfunction has been suggested by a low phosphocreatine:Pi ratio and a possible response by migraine patients to riboflavin prophylaxis. Nitroglycerine administration results in a delayed migraine-like headache in migraine patients but not in control patients, and a nonspecific nitric oxide synthase inhibitor aborted migraine at 2 hours in the majority of tested migraine patients compared to controls. Many patients with familial hemiplegic migraine have a missense mutation in the P/Q calcium channel, so that this form of migraine, at least, is associated with a demonstrable calcium channelopathy. CONCLUSIONS: The generation of migraine occurs centrally in the brain stem, sometimes preceded by cortical spreading depression and aura. Activation of the trigeminovascular system stimulates perivascular trigeminal sensory afferent nerves with release of vasoactive neuropeptides, resulting in vasodilation and transduction of central nociceptive information. There is then a relay of pain impulses to central second- and third-order neurons and activation of brain stem autonomic nuclei to induce associated symptoms.

Journal Article↗
PubMed2003

Are fingers special? Evidence about movement preparation from event-related brain potentials.

Ulrich, Leuthold, and Sommer (1998) suggested that movement preparation at the level of the motor cortex, as indexed by the lateralized readiness potential (LRP), proceeds in a strongly hierarchical fashion, where parameters other than response hand are prepared only if all the movement parameters are known. These conclusions were based on an experiment where a precue provided information about response hand, direction of finger movement, and movement force. To assess the generality of these findings, we replaced the force parameter with response finger. LRP indicated that preparation of the required finger is possible even when preliminary information is incomplete. Therefore, movement preparation appears to follow different rules when anatomical relationships (hand and finger) are concerned as compared to functional parameters like movement direction. On the other hand, at a limb-unspecific level, as indicated by the contingent negative variation, we confirmed evidence for parallel programming of all movement parameters.

Adult↗
PubMed2003

Developmental differences in behavioral and event-related brain responses associated with response preparation and inhibition in a go/nogo task.

The present study investigated developmental trends in response inhibition and preparation by studying behavior and event-related brain activity in a cued go/nogo task, administered to nine-year-old children and young adults. Hits, false alarms, inattention, and impulsivity scores and ERP measures of inhibition (fronto-central nogo-N2 and P3), target selection (parietal go-nogo P3 difference), and response preparation (contingent negative variation; CNV) were collected. Higher false alarm and impulsivity scores and the absence of the fronto-central nogo P3 all suggest a developmental lag in response inhibition in children. A developmental lag in sustained attention processes was suggested by worse target detection and larger parietal target/nontarget P3 effects in children. Cue orientation and response preparation processes were respectively measured by early and late CNV activity. Children displayed smaller early CNV amplitudes at fronto-central locations, but mature late CNV. The smaller early CNV activity might indicate inefficient cue-orientation processes caused by incomplete frontal lobe development.

Adult↗
PubMed2002

Slow event-related brain activity of aphasic patients and controls in word comprehension and rhyming tasks.

Slow event-related potentials (ERP) were examined in healthy and aphasic subjects in two-stimulus designs comprising a word comprehension and a rhyming task. Aphasics, though selected to perform above chance level, made significantly more errors and responded more slowly than controls, although canonical correlations did not indicate a statistical relationship between performance measures and ERP amplitudes. A discriminant analysis of ERP amplitudes distinguished the groups for the slow wave (SW; 0.5-1.0 s post-S1 onset) in the word comprehension, for the SW and the initial contingent negative variation (iCNV; 1.0-2.0 s post-S1 onset) in the rhyming task. Similarly for both tasks, ERP topography showed left-anterior predominance of the negative SW and iCNV in controls, whereas participants with aphasia showed smaller anterior and larger left-posterior amplitudes. The centroparietal terminal CNV (tCNV; 1 s pre-S2) was smaller in participants with aphasia than in controls, but similar in topography. Results suggest left-anterior activation for those language processes that were presumably provoked in the present tasks, like lexical access, or phonological encoding. The pattern of participants with aphasia may indicate effects of language impairment and recovery, but also consequences of the brain damage.

Adult↗
PubMed2006

Varieties of attention in neutral trials: linking RT to ERPs and EEG frequencies.

It is often assumed that when a neutral cue is presented in a spatial cueing task, attention remains at fixation until target onset. We hypothesized that variance in nonspatial attention and switches of attention toward target locations can account for variance in reaction times of neutral trials. Lateralized event-related potentials (ERPs) and changes in electroencephalogram (EEG) frequency bands served as predictor variables in a single-trial logistic regression analysis to predict the direction of spatial attention in cued and neutral trials. The contingent negative variation (CNV) and non-lateralized changes in the alpha band served as markers of nonspatial attention. The direction of attention in cued trials was reliably predicted from single-trial lateralized ERP components. In neutral trials, only evidence for nonspatial attention was found, indicated by increases in the CNV and decreases in alpha preceding targets to which responses were relatively fast.

Adult↗
PubMed1971

Rubella: will vaccination prevent birth defects?

In the report "Attention-related increases in cortical responsivity dissociated from the contingent negative variation" by M. W. Donald, Jr., and W. R. Goff [172, 1163 (1971)] line 12 of reference 20 should read "P300 and CNV with performance efficiency."

Adult↗
PubMed2005

Parkinsonism following bilateral lesions of the globus pallidus: performance on a variety of motor tasks shows similarities with Parkinson's disease.

OBJECTIVES: The authors report the results of detailed investigations into the motor function of a patient who, after a heavy drinking binge and subsequent unconsciousness, respiratory acidosis, and initial recovery, developed parkinsonism characterised by hypophonic speech and palilalia, "fast micrographia", impaired postural reflexes, and brady/akinesia in proximal (but not distal) alternating upper limb movements. METHODS: In addition to brain magnetic resonance imaging (MRI), different aspects of motor function were investigated using reaction time (RT) tasks, pegboard and finger tapping tasks, flex and squeeze tasks, movement related cortical potentials (MRCPs), and contingent negative variation (CNV). Cognitive function was also assessed. The results were compared to those previously reported in patients with Parkinson's disease (PD). RESULTS: Brain MRI showed isolated and bilateral globus pallidus (GP) lesions covering mainly the external parts (GPe). These lesions were most probably secondary to respiratory acidosis, as other investigations failed to reveal an alternative cause. The results of the RT tasks showed that the patient had difficulties in preparing and maintaining preparation for a forthcoming movement. MRCP and CNV studies were in line with this, as the early component of the MRCP and CNV were absent prior to movement. The patient's performance on pegboard and finger tapping, and flex and squeeze tasks was normal when performed with one hand, but clearly deteriorated when using both hands simultaneously or sequentially. CONCLUSIONS: In general, the present results were similar to those reported previously in patients with PD. This provides further indirect evidence that the output of globus pallidus is of major importance in abnormal motor function in PD. The possible similarities of the functional status of GP in PD and our case are discussed.

Acidosis, Respiratory↗
PubMedDate not supplied

Tinnitus and event-related activity of the auditory cortex.

A neuromagnetic study in tinnitus patients and normal-hearing controls was performed with a modified contingent negative variation (CNV) paradigm. While the warning stimulus S1 was a tone burst at an intensity well above threshold, the imperative stimulus S2 was presented at a near threshold intensity because, in the majority of cases, the perceived loudness of tinnitus is very close to the threshold for a pure tone of the same frequency. Subjects had to respond to S2 by pressing a button until its offset was detected. In this case, instead of the usual sudden cut-off of the CNV after the perception of S2, a slow negative deflection develops, the post-imperative negative variation (PINV). Its initial portion probably indicates the development of a second initial CNV because the subject had to attend also to the offset of S2. The neuromagnetic data were analysed both in the time domain and in the frequency domain (short-time spectral analysis of the classical EEG bands). The time domain waveform as well as the spectrotemporal patterns of the MEG bands exhibited deviations from the normal pattern in several tinnitus subgroups, depending on the characteristics of tinnitus (tonal vs. noisiform, monaural vs. binaural) and on the stimulation conditions (tinnitus side vs. non-tinnitus side).

Adolescent↗
PubMed1984

Electrophysiological (CNV) analysis of personality traits under stress.

Contingent negative variation (CNV) recordings were performed in 55 healthy volunteers under stress condition (experimentally induced pain). A total of 20 subjects were included in the control group (no painful administration). In the tested group (n = 35) the painful stimulus was delivered before S1, between S2 and S1, and before S2. In the control group there were no changes in CNV parameters. Conversely, among the tested group a positive correlation was found between CNV values (whenever the painful stimulus was administered before S1 as well as before S2) and the highest scores in the State Trait Anxiety Inventory X 2 test. In addition, all individuals displayed the appearance of a positive deflection with a latency of about 300 ms from S2 when the experimental stress was given before S2. Furthermore, the postimperative negative variation (PINV) appeared in 13 out of 35 subjects. There was a strong correlation between the latter electrophysiological phenomenon and the Nowlis test. Our findings suggest that CNV study is useful for the investigation of personality traits in human beings under stress conditions.

Adult↗
PubMed1985

Effects of tobacco and distraction on sensory and slow cortical evoked potentials during task performance.

Sensory and slow cortical evoked potentials (EP) of female smokers were investigated under two conditions in separate sham and real smoking sessions: a non-distraction (ND) condition consisting of a constant fore-period S1-S2, i.e., a single-choice reaction time situation with a tone (S1)/light (S2) key press sequence, and a task distraction (TD) condition identical to ND with the addition of a short-term memory task consisting of four letters presented within the S1-S2 interval with the requirement that subjects repeat after key press to the light. Two individual EP peaks, N1 and P2, were involved in the amplitude analysis of S1 and S2 stimuli; in addition, the amplitude of the slow contingent negative variation (CNV) developing between S1 and S2 was analyzed. Tobacco significantly altered the amplitude of P2 in response to S1 and CNV amplitudes depending on the pre-experimental expired air carbon monoxide (CO) levels of the smokers. Smokers exhibiting low pre-experimental CO levels evidenced tobacco-induced P2 reductions and CNV increments during the ND condition while subjects exhibiting high pre-experimental CO levels displayed similar cortical changes but in the TD conditions. The results are discussed in relation to the role of nicotine and to improved attention and information processing.

Adult↗
PubMed1987

Rapid information processing and concomitant event-related brain potentials in smokers differing in CO absorption.

The present study relates subject-paced rapid information processing to different components of event-related brain potentials in an attempt to gain more information about changes in mental performance in relation to alveolar smoke absorption as assessed by expired air CO measurement. The task consisted in the presentation of pseudorandom sequences of single digits, and the subjects had to respond to each sequence of three odd or three even digits. The triplets evoked a typical late negativity in the event-related potential between the second and third digit as well as a P300 component following the third digit. In 21 smokers, task performance, event-related potentials and tidal air CO concentration were measured before and after smoking a cigarette. The results revealed increases in performance and P300 magnitude from pre- to postsmoking which were unaffected by the amount of CO absorption. A differential trend was seen, however, with the late negativity, which increased from pre- to postsmoking only in subjects with a large amount of CO absorption. The results support the assumption of the distraction arousal model used as an interpretation of these effects on contingent negative variation and suggest that high CO absorbing smokers possibly depend more on neuropharmacological effects of smoking than smokers with a low amount of CO absorption.

Adolescent↗
PubMed1998

Event-related potentials (P300) in primary headache in childhood and adolescence.

There is strong evidence for a loss of habituation during cognitive processing in migraine as measured by P300 and contingent negative variation in adults. Event-related potentials evoked by an oddball paradigm have not yet been studied in children and adolescents suffering from different primary headache types. We recorded visually evoked event-related potentials (two consecutive trials, 200 stimuli each) in 48 children and adolescents suffering from migraine without or with aura, from episodic tension-type headache, and from ergotamine-induced headache and analyzed the latencies, amplitudes, and reaction times. No statistically significant differences were noted between all headache types and healthy controls analyzing the averaged parameters for the whole measurement. However, a highly significant loss of cortical habituation as measured by P300 amplitude and latency could be observed in migraine without and with aura by analyzing the first and the second trial of measurement separately. This phenomenon increased with age and could not be seen in healthy controls, or patients with tension-type headache or ergotamine-induced headache. Our data suggest a specific cognitive processing in migraine even in children and adolescents. Measurement of the habituation effect in P300 latency and amplitude provides a specific method to differentiate between primary headache types in childhood and adolescence.

Adolescent↗
PubMed2003

Electrophysiology of the frontal lobe.

The electrophysiology of the frontal lobe appears to be unimpressive when the view is limited to the routine EEG recording of a healthy waking adult. There is usually low voltage fast activity, which becomes more pronounced when recorded with depth leads. Three special EEG patterns of marginal to slightly abnormal character are discussed: a) rhythmical midfrontal 6-7/sec activity of juveniles, b) rhythmical midfrontal sharp 4-6/sec activity of infancy and early childhood with arousal from sleep, and c) frontal intermittent rhythmical delta activity (FIRDA) in waking adults with frontopolar maximum, possibly related to thought processes under abnormal conditions. With extension of the frequency range, ultraslow (DC-like) as well as fast beta (gamma, 40-80/sec) and ultrafast activity (80-1000/sec) are found particularly over the frontal lobes. Ultraslow baseline shifts are arousal-related and mixed with overlying ultrafast waves. Attention control and the "working memory" involve chiefly the dorsolateral prefrontal cortex, investigated with P300 responses and likely to show ultrafast spectra. Perception-related 40-80/sec gamma activity has been thought to be associated with the entrance into consciousness. Initiation and design of motor activity spreads from prefrontal to the frontomotor cortex, associated with powerful event-related potentials: contingent negative variation (CNV) and "Bereitschafts potential" ("readiness potential," RP). Neuroscientific research of the highest frontal lobe functions has become a very active domain of neuroimaging. With the use of the extended frequency range, EEG and also evoked potential studies could add further information with acquisition in real time. Ultrafast frequency ranges presented in computerized frequency analysis and mapping might show impressive correlates of highest frontal lobe functions.

Arousal↗
PubMed2000

Human movement-related brain potentials preceding voluntary movements in different arousal states monitored with skin potential level.

The present study investigated the readiness potential (RP) preceding a brisk extension of the right middle finger during different arousal states as monitored by skin potential level (SPL). The late component of the readiness potential in the medium arousal state was significantly larger than those in the low and high arousal states. This finding indicates that the RP waveform may vary as a function of arousal states, suggesting the inverse U-shaped relationship proposed in studies of the contingent negative variation.

Arousal↗
PubMed1986

Slow brain potentials and the "tunnel effect".

The present study investigated electrocortical concomitants of the "tunnel effect." The tunnel effect refers to the following perceptual phenomenon: if a continuously moving object disappears behind a shield ("enters a tunnel") the observer has the impression that the same object continues to move with the time point of reappearance usually being underestimated. In the present study, an object moved across a tv-screen for 6 s; it either disappeared behind a shield (tunnel condition), disappeared at once (explosion condition), or remained visible until the end of its trajectory (control condition). Subjects had to press a button whenever they believed that the object had arrived at its trajectory's end. The object's flight was accompanied by a continuously rising slow negative shift of the EEG that resembled the contingent negative variation (CNV). Either type of object disappearance produced a positive-going potential that may reflect brain processes associated with memory rehearsal and/or time estimation. A late P300-like positivity was prominent under tunnel conditions only. Response latency was shorter under disappearance than under control conditions. The positive deflection is discussed as sign of amodal brain processing (memory rehearsal and/or time estimation). The P300-like wave elicited by the object's disappearance activates these memory representations. Based on these considerations, an attempt was made to interpret the premature motor responses, which are commonly observed for tunnel conditions but not for other time estimation tasks.

Brain↗
PubMed1990

Lateralized effects of migraine and ANS seizures after closed head injury.

Theoretical issues associated with memory, neurocognitive and noradrenergic mechanisms in posttraumatic migraine and dysautonomic complex-partial seizure disorders are reviewed, compared and discussed. Additionally, pretreatment Contingent Negative Variation (CNV) was recorded in a No-GO/GO reaction-time paradigm for 15 normal, and 18 posttraumatic migraine and seizure patients tested not more than three months postinjury. Normals demonstrated that CNV GO and NO-GO responses significantly differed. In both migraine and seizure patients GO and NO-GO trials did not differ significantly. In uncontrolled trials, it was noted that B-Blocker administration increased the difference between GO and NO-GO trials for both migraine and seizure patients over midline leads.

Acoustic Stimulation↗