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PubMed1995

[Olfactory evoked potentials and contingent negative variation in expert assessment of disordered sense of smell].

Normally, the sense of smell is assessed by means of traditional subjective tests (sniff test, gustatory smell test, and trigeminus test). When results are inconclusive, an objective smell test is indicated. Simultaneously registering olfactory evoked potentials (OEP) and contingent negative variation (CNV) permits evaluation of both odor perception and odor discrimination. We can even objectively assess the false olfactory sensations in parosmia patients who are unable to discriminate between different odors. In this study, the results of 59 patients with olfactory disorders are presented. Head trauma and upper respiratory infections were the most common causes of the patients' complaints. In twelve cases, lack of cooperation and patient unrest prevented us from evaluating the data. In anosmia, the objective results agreed completely with the patient's subjective assessment. In hyposmia and parosmia, the results agreed with the patient's subjective assessment in most cases; here we were able to arrive at a more specific diagnosis in several cases. The objective smell test can be used to supplement subjective methods and thus provide more reliable assessment of olfactory disorders.

Attention↗
PubMed1994

Perimenstrual migraine: effect of Estraderm TTS and the value of contingent negative variation and exteroceptive temporalis muscle suppression test.

In 20 patients with pure menstrual migraine either Estraderm TTS 50 patches (E) or placebo (P) patches were applied during three successive menstrual cycles, randomly allocated to the treatment sequences E-P-E or P-E-P. Clinical neurophysiological tests, contingent negative variation (CNV) and exteroceptive temporalis muscle suppression test (ETST) were performed before treatment. The predictive value of these tests regarding the efficacy of Estraderm TTS was studied. Neither the number, duration and severity of the migraine attacks, nor the consumption of analgesics and ergotamine differed significantly during Estraderm TTS and placebo treatment. The ETST was consistent with migraine in 35% (95% confidence interval 15.4 to 59.2) of the patients. The CNV in 55% (31.5 to 76.9), and both tests in 25% (8.7 to 49.1%). Regarding the prediction of the Estraderm TTS effect on the migraine attacks, the specificity of the ETST, CNV and the combination of ETST with CNV, calculated for the first two cycles, was respectively 81.8% (48.2 to 97.7), 45.5% (16.8 to 76.6) and 80% (28.4 to 99.5). For the last two cycles these values were respectively 75% (42.8 to 94.5), 50.0% (21.1 to 87.9) and 71.4% (29.0 to 96.3). The sensitivity of the tests was respectively 62.5% (24.5 to 91.5), 62.5% (24.5 to 91.5) and 66.7% (22.3 to 95.7) in the first 2 cycles. In the last 2 cycles 50.0% (15.1 to 84.3), 62.5% (24.5 to 91.5) and 60% (14.7 to 94.7). This study did not demonstrate an effectiveness of Estraderm TTS in perimenstrual migraine, except for the subgroup of perimenstrual migraine patients in whom the ETST test results were consistent with migraine.

Administration, Cutaneous↗
PubMed1995

Fear conditioning, preparedness, and the contingent negative variation.

Psychophysiological research on preparedness has previously focused on autonomic nervous system parameters. The present study used electrocortical indices of fear conditioning. Subjects (n = 10) were tested under fear-relevant and fear-irrelevant conditions (1 week apart, order of conditions counterbalanced). Each condition comprised acquisition and extinction sessions. The contingent negative variation (CNV) was elicited in anticipation of forewarned slides (fear relevant: small animals; fear irrelevant: landscapes). In acquisition, reinforced conditioned stimulus (CS+) (but not nonreinforced conditioned stimulus [CS-]) slides were followed by white noise as an unconditioned stimulus (UCS). In extinction, the UCS was omitted. In the fear-relevant condition, CNV amplitude was significantly larger for CS+ than CS- in both acquisition and extinction. In the fear-relevant condition, CNV amplitude was significantly larger for CS+ than CS- in both acquisition and extinction. In the fear-irrelevant condition, CNV differentiation between CS+ and CS- was weak in both sessions. CNV was significantly larger in the fear-relevant than in the fear-irrelevant condition, for CS+ but not CS-. The findings are consistent with a preparedness interpretation and suggest that CNV under such circumstances may represent an automatic affective response to fear-relevant stimuli. Electrocortical measures could be particularly useful in examining information processing mechanisms in phobia and cognition-affect relationships generally.

Adolescent↗
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↗
PubMed2001

Uncoupling of contingent negative variation and alpha band event-related desynchronization in a go/no-go task.

OBJECTIVES: To examine how the differences in the sequences of brain activation during the go/no-go delayed response choice reaction time (RT) task are reflected into two concurrent methods of measuring brain electrical activity, the alpha band event-related desynchronization (alpha ERD) and the contingent negative variation (CNV). METHODS: alpha ERD and CNV were calculated using appropriate techniques from the same samples of electroencephalographic activity recorded during performance of a cued choice go/no-go delayed response RT task (i.e. S1 (go/no-go)--S2 paradigm) in 8 healthy subjects. RESULTS: All segments of the CNV traces were different in the go and the no-go conditions. The go CNV traces displayed a typical pattern of slow rising negativity reflecting the build-up of attentional resources necessary for adequate performance of the task. On the other hand, the no-go traces remained close to zero reflecting the 'withdrawal' of further preparation after evaluation of S1. During the same period, both go and no-go ERD traces showed a gradual decrease in alpha band power (desynchronization) that was evident until shortly before the presentation of S2. It was only in the 500 ms before S2 presentation that there was any indication that the go and no-go ERD traces were different, but this did not reach statistical significance. CONCLUSIONS: Our data show that the pattern of the go/no-go difference in alpha ERD traces does not correspond to the pattern that can be seen in the CNV traces. This suggests that there is no direct coupling of CNV and alpha ERD, most probably because they measure different aspects of cortical electrical activity. In addition, the extent of the no-go alpha ERD reveals that refraining from performance of a pre-programmed movement is by no means a passive/inactive process.

Adult↗
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↗
PubMed2001

Contingent negative variation in subjects at risk for migraine without aura.

Migraine is a complex disease with a significant genetic background. One possible strategy to investigate the genetics of migraine is the evaluation of functional vulnerability markers or biological elementary endophenotypes in individuals with the greatest probability of developing the disorder (high-risk design). In this study the contingent negative variation (CNV) was recorded in 35 high-risk subjects with a positive family history of migraine without aura (FHP), 35 low-risk individuals without a positive family history (FHN), and 35 migraineurs (migraine without aura). FHP subjects and migraine patients differed significantly from FHN individuals with regard to amplitude and habituation slope of the early CNV component (initial CNV or iCNV). FHP participants demonstrated the same iCNV abnormalities and distribution among iCNV characteristics as migraineurs. The amplitude of the iCNV correlated significantly with the relative number of subjects suffering from migraine among first- and second-degree relatives. The higher the density of affected individuals in the family, the more pronounced were the CNV abnormalities in relatives. This study provides evidence that the familial factor contributes to the abnormal amplitude, and to a lesser degree, habituation of the iCNV, and that the iCNV may be used as a functional-genetic vulnerability marker in further research of migraine genetics.

Adolescent↗
PubMed2001

Contingent negative variation and attentional performance in humans.

The relation between a paper-pencil test of sustained attention (d2-letter cancellation test, d2-LCT) and the contingent negative variation (CNV) as a cortical slow potential was calculated in 23 healthy undergraduate students. Both d2-LCT and CNV reflect selective, focussed attention. There was a Pearson correlation coefficient of r = -0.670 between the early component of the CNV and the number of checked letters in d2-LCT, indicating significant differences in early CNV between low and high performance in d2-LCT. The results showed a linear relationship between paper-pencil registered attentional properties and the cortically recorded early component of CNV.

Adult↗
PubMed2000

High resolution spatiotemporal analysis of the contingent negative variation in simple or complex motor tasks and a non-motor task.

OBJECTIVES: Since the characteristics of the Bereitschaftspotential (BP) - voluntary movement paradigm of internally-driven movements - have been established recently by our group using high resolution DC-EEG techniques, it was of great interest to apply similar techniques to the other slow brain potential--contingent negative variation (CNV) of externally-cued movements--with the same motor tasks using the same subjects. METHODS: The CNV for simple bimanual sequential movements (task 1), complex bimanual sequential movements (task 2) and a non-motor condition (task 3) was recorded on the scalp using a 64 channel DC-EEG in 16 healthy subjects, and the data were analyzed with high resolution spatiotemporal statistics and current source density (CSD). RESULTS: (1) The CNV was distributed over frontal, frontocentral, central and centroparietal regions; a negative potential was found at the frontal pole and a positive potential was found over occipital regions. (2) CNV amplitudes were higher for task 2 than for task 1, and there was no late CNV for task 3. (3) A high resolution spatiotemporal analysis revealed that during the early CNV component, statistical differences existed between the motor tasks (tasks 1 and 2) and the non-motor task (task 3), which occurred at frontocentral, central, centroparietal, parietal and parieto-occipital regions. During the late CNV component, additional significant differences were found not only between the motor tasks and the non-motor task but also between motor task 1 and task 2 at frontocentral, central and centroparietal regions. (4) Comparison of the CNV between the frontomesial cortex (situated over the supplementary/cingulate areas, SCMA) and both lateral pre-central areas (situated over the primary motor areas, MIs) showed that there was no statistically significant difference between the two cortical motor areas except for the early CNV. (5) Comparison of the CNV between the 3 tasks over the cortical motor areas showed that there were significant differences between the motor tasks and the non-motor task regarding the auditory evoked potential (AEP) and the early CNV component, and between all 3 tasks in the late CNV, the visual evoked potential (VEP(2)) and the N-P component. (6) The ranges and the densities of the CSD maps were larger and higher for complex than for simple tasks. The current sinks of the AEP and the early CNV were located at Fz, the late CNV at FCz and surrounding regions. As to be expected, current sources of the VEPs were located at the occipital lobes. The CNV was a current sink (negative) except for the VEP's main component which was a current source (positive). CONCLUSIONS: (1) The CNV topography over the scalp varied with the complexity of motor tasks and between motor and non-motor conditions. (2) The origin of the early CNV may rest in the frontal lobes, while the late CNV may stem from more extensive cortical areas including SCMA, MIs, etc. (3) The late CNV component is not identical with the BP.

Adult↗
PubMed1999

Slow EEG potentials (contingent negative variation and post-imperative negative variation) in schizophrenia: their association to the present state and to Parkinsonian medication effects.

Between warning signal (S1) and imperative signal (S2), the EEG shifts negatively (contingent negative variation, CNV) reflecting preparation and expectancy. Reduced CNV and continued negativity after S2 (post-imperative negative variation, PINV) have been repeatedly found in schizophrenic patients and have been interpreted as a deficit in attentional processes (CNV) and as uncertainty about the correctness of one's own response to the S2 (PINV). Recent studies obtained a CNV reduction specifically at central sites but not at frontal ones. The present study investigated whether these alterations of slow negative potentials depend on present state of symptoms, on the particular task used, and on neuroleptic medication. Therefore, out-patients and in-patients were studied, two different S1-S2 tasks were used, and the control groups were healthy subjects and patients with Parkinson's disease. The central CNV reduction was stable across tasks and across in-patients and outpatients. Frontal CNV was reduced in in-patients but in only one of the two tasks in outpatients. The schizophrenic patients' enhanced PINV was larger contralaterally than ipsilaterally to the responding hand, correlated with medication, and occurred in similar way in patients with Parkinson's disease. Thus, the PINV increase might reflect the Parkinsonian side effects of the anti-psychotic medication. In contrast, the central CNV reduction appears as a stable marker of schizophrenia, the frontal CNV reduction as a state-dependent effect. The central CNV reduction might reflect impairment in forming stable stimulus-response associations, the relative frontal enhancement might reflect the out-patients' attempt at compensating that impairment.

Adult↗
PubMed1996

Effects on contingent negative variation of set created by anticipating variable foreperiods.

The influence of set on a simple reaction time task was examined by comparing the differences of psychological factors between a group of subjects who expected and experienced a fixed foreperiod Control condition: 12 subjects) and another group of subjects who were instructed to expect variable foreperiods but experienced the same fixed foreperiod (Instruction condition: 11 subjects), using the index of contingent negative variation (CNV). The foreperiod of simple reaction time task in each condition was fixed at 3 sec. Subjects were required to respond to 2 blocks of 24 trials, and each instruction was presented between blocks. On the second block CNV amplitudes were higher in the instruction condition as was every CNV component (early late, and whole component). The set created by anticipating variable foreperiods seems to increase cerebral activity, arousal, and attention during simple reaction time tasks.

Adolescent↗
PubMed1982

Action of lysine-vasopressin on human electroencephalographic activity. Night sleep pattern, auditory evoked potential, contingent negative variation.

This study is an investigation of the central effects of vasopressin in man, as this hormone proved able to modify learning processes in animals and was applied successfully to post-traumatic, amnesic patients. Electrophysiological techniques were used to assess the effects of lysine-vasopressin (LVP) given by nasal spray (7 and 14 IU) on night sleep pattern (12 subjects), auditory evoked potentials (AEP; 26 subjects), and contingent negative variation (CNV; 26 subjects). Night sleep EEG was not modified to a great extent: in particular REM sleep did not undergo any change after LVP. Nor were AEPs modified, either in the 6-hour period following drug administration or 1 week after; CNV, however, reacted in a significant manner 6 h after drug intake, and the modifications were still present after 1 week. LVP did not affect CNV amplitude itself but its evolution through time, as CNV habituation was prevented. Such effects are discussed with regard to the neurochemical mechanisms of vasopressin action and CNV genesis.

Administration, Intranasal↗
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↗
PubMed2002

Motor circuitry re-organization after pallidotomy in Parkinson disease: a neurophysiological study of the bereitschaftspotential, contingent negative variation, and N30.

The aim of the study was to evaluate the reorganization changes in the motor circuitry of the basal ganglia following unilateral posteroventral pallidotomy in Parkinson disease (PD) patients using neurophysiological paradigms. Eight advanced PD patients received a neurophysiological battery 2 months prior and 6 months after unilateral pallidotomy. Examinations were all performed in the practically defined "off" situation. Bereitschaftspotential (BP) and N30 were recorded for each hand alternately. Contingent negative variation (CNV) was obtained using a visual Go/no-Go paradigm. ANOVAs (electrode position; surgery) were applied for BP and CNV results. N30 data were analyzed using Wilcoxon matched-pair tests. A significant increase in amplitude of the late component (NS') of the BP was evidenced with patient performing with the hand contralateral to pallidotomy. No significant amplitude differences were found in CNV after surgery in any lead, or in any of the time windows tested. A trend toward significance was observed corresponding to a postsurgical numerical increase in amplitude of the N30 peak in the hand contralateral to pallidotomy. These results suggest that neurophysiological changes after pallidotomy are mainly in the last stages of movement preparation and execution.

Adaptation, Physiological↗
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↗
PubMed2001

Contingent negative variation in children with orthostatic dysregulation.

BACKGROUND: Children with orthostatic dysregulation (OD) appear to have hypodynamia, as well as the symptoms described in the OD criteira. Hypodynamia, which is greatly influenced by motivation, volition and concentration, is unexceptionally recognized in their everyday life. It has been suggested that the symptoms and hypodynamia aggravate considerably the quality of life (QOL) of children with OD. The purpose of this study was to distinguish the characteristics of contingent negative variation (CNV) and post imperative negative variation, which may reflect the level of attention and motivation in children with OD. METHODS: Twelve patients with OD aged 10-15 years and 23 age-matched healthy children were included. The CNV was recorded from Fz, Cz and Pz linked to earlobes during 30 trials consisting of a warning stimulus and an imperative stimulus with an interstimulus interval (ISI) of 2 s and an intertrial interval (ITI) of 10 s. The imperative stimulus of each trial required a button to be pressed. RESULTS: The untreated children with OD did not have a significantly smaller CNV amplitude than healthy children. Children with OD treated with midodrine and autonomic training had a significantly larger CNV amplitude than the untreated children, in the area of early, late and total CNV at the three sites. CONCLUSION: The present study confirms that children with OD have diminished motivation and deterioration of concentration, which cause hypodynamia in everyday life. Treatment for OD improves the symptoms, diminished motivation and deterioration of concentration, consequently restoring dynamia. Treatment for OD should be recommended to ameliorate QOL of children with OD.

Adolescent↗
PubMed1998

Event-related desynchronization to contingent negative variation and self-paced movement paradigms in Parkinson's disease.

The event-related desynchronization (ERD) to voluntary movement is an indicator of cortical activation with a high time resolution and a specific spatial representation. We have evaluated 10 patients affected by Parkinson's disease (PD), free from L-dopa treatment for at least 12 hours, and 10 control subjects. Each subject underwent ERD examination during self-paced movement (SPM) and during contingent negative variation (CNV) paradigms. ERD was measured as the percentage decrease of alpha band power and calculated for frequency bands of 1 Hz, ranging between 8 and 12 Hz. For group comparisons, the frequency showing the highest ERD was selected for each subject and for each side. In the control group, ERD in the CNV paradigm began over the contralateral centroparietal electrodes 1475 ms before movement onset of the right hand and 1375 ms for the left. In the SPM paradigm, ERD started over the contralateral central electrodes 2150 ms and 1775 ms before movement onset of the right and left hand, respectively. In the PD group, ERD started over the contralateral central areas 800 ms and 475 ms before movement onset of the right and left hand, respectively, for CNV paradigm and 1200 ms and 750 ms for the right and left hand, respectively, for SPM paradigm. Therefore, contralateral ERD began closer to movement onset in PD compared with the control group in both paradigms. ERD over the sensorimotor areas ipsilateral to the movement was not significantly different in PD compared with the control group. The finding of delayed contralateral ERD in PD is according to the view that functional cortical activation related to movement preparation is impaired in PD. The lack of group differences in the onset of ipsilateral ERD, which appears close to movement execution than contralateral ERD both in normal subjects and in PD, suggests that different mechanisms may be involved in generating ERD over the hemispheres ipsilateral and contralateral to the movement, and that only the latter are impaired in PD.

Adult↗