立体定向手术对精神分裂症患者事件相关电位的影响

目的：探讨脑立体定向手术对军人慢性难治性精神分裂症患者3种事件相关电位的影响。方法：以40例难治性精神分裂症患者为手术组，43例条件相匹配的非手术患者为对照组。在脑立体定向手术治疗前、后，对两组患者分别进行事件相关电位N400（N400）、失配性负波（MMN）和关联性负变（CNV）检查，以阳性与阴性症状量表（PANSS）评定疗效。结果：与治疗前比较，手术组CNV潜伏期M1缩短，命令信号后负变化（PINV）出现率下降，N400潜伏期缩短（P均〈0．05），MMN各指标变化不明显；手术组PANSS总分及各因子（除阴性症状因子）分均明显下降（P〈0．05或P〈0．01）；对照组N400、MMN、CNV和PANSS各项指标变化不明显。治疗后两组比较差异有显著性（P〈0．05）。结论：立体定向手术改善了军人慢性难治性精神分裂症患者的认知功能和精神症状。     

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.     

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.     

How the brain anticipates an attack: a study of neurophysiological periodicity in migraine.

We investigated cortical excitability and the pattern of arousal in migraine patients using contingent negative variation (CNV) and EEG power spectrum analysis performed before and after a migraine attack. Twenty females suffering from migraine without aura and 12 healthy controls were enrolled in the study. In the group of patients, the CNV, EEG power spectrum and hemispheric asymmetry analyses were performed 1-4 days before the first day of an attack and 4 days following the last day with migraine. The recordings in healthy subjects were carried out on a day chosen by the participants. The comparisons were made using non-parametric procedures. After an attack no difference was found between patients and controls in EEG power spectrum, hemispheric asymmetry or CNV components (with the exception of the beta 1 power, which was more pronounced in patients). Before an attack, however, a significant increase in the power of delta and theta frequency bands, in the alpha asymmetry, and in early CNV amplitude were observed. The patients differed from controls both in the extent of cortical excitability and in the arousal pattern found. In such a way migraine is characterized by periodic CNV and EEG power spectrum changes during the pain-free interval. The abnormalities in cortical excitability and arousal were only observed before an attack, and could be used to predict the next migraine episode. We assume that these changes reflect the increased susceptibility of the migrainous brain to precipitating factors and the neurophysiological readiness to generate an attack. The time duration since the last attack must be taken into account when performing studies in the field of migraine research.     

气功所致精神障碍患者脑诱发电位系列实验研究

目的 研究气功所致精神障碍患者与正常人在诱发了诱发电位的检测中的不同特点。方法 应用美国仪器和四种方法，对１２例气功偏差所致精神障碍患者和５２例正常人的诱导电位作了检测。结果 与正常人比较，患者组ＡＥＰ的Ｐ１、Ｐ２、Ｎ２、Ｐ３；ＶＥＰ的Ｎ１、Ｎ２、Ｐ３和ＳＥＰ的Ｐ２潜伏期均明显延迟ＡＥＰ、ＶＥＰ和ＳＥＰ的若干波幅同时明显改变。另在ＣＮＶ中机见Ｐ１ＮＶ和Ａ－Ｃ潜伏期延迟，波畅Ｂ增大，Ａ－Ｓ２＾－和Ｓ     

Contingent negative variation in headache

Contingent negative variation (CNV), an event-related slow cerebral potential, was analyzed in 79 consecutive headache patients. Compared to normal controls (n = 33), CNV did not differ in tension headache (n = 21) or in combined headaches with a predominant tension component (n = 13). The mean amplitude of CNV was significantly (p less than 0.001) increased in migraine (n = 29) as well as in combined headache with predominant migraine (n = 16). All migraineurs were studied between attacks and without prophylactic treatment. CNV may be a useful diagnostic test in headache. Its increased amplitude in migraine might reflect central catecholaminergic hyperactivity.     

Contingent negative variation before and after hemodialysis among patients with end-stage renal disease

OBJECTIVE: To investigate changes in contingent negative variation (CNV) induced by uremia and to study the effects of hemodialysis. METHODS: Fifteen right-handed healthy subjects and 12 patients with end-stage renal disease (ESRD) were studied. CNV was recorded from the Fz, Cz and Pz (using the International 10-20 System) referenced to linked ear lobes, using an S1 (click)-S2 (flashes)-key press paradigm. The amplitude of initial CNV (iCNV) was calculated as the average amplitude at 550-750 ms after S1. The amplitude of late CNV (lCNV) was the mean amplitude of the last 200 ms before S2. Testing was repeated for the patient group at pre- and post-hemodialysis observations. Neuropsychological measurements, a trail making test (TMT) and mini-mental state examination (MMSE), were conducted at each time. RESULTS: The mean amplitudes of iCNV and lCNV at the vertex (Cz) were both significantly lower in the patient group than in the control group (P<0.05). TMT were also significantly different between patient and control groups (P<0.05)), however MMSE showed no significant difference. There were no significant correlations between the values of neuropsychological tests and the parameters of CNV. Both iCNV and lCNV were not significantly different between the pre- and post-dialysis tests. CONCLUSION: CNV negativity in patients with ESRD reflects diffuse nonlocalizing neurological symptoms of uremia rather than a selective involvement of the frontal lobes. It is likely to reflect dysfunction in the frontal-subcortical circuit. In addition, hemodialysis seemed to have no significant effect on executive brain function in these patients with ESRD.     

Postimperative negative variation (PINV) in ambulatory schizophrenic patients.

The contingent negative variation (CNV), first described by Walter in 1964,¹ is considered today as a cerebral phenomenon and not as an artifact from some extracerebral source. The CNV is recorded at vertex during the presentation of two successive stimuli, S₁-warning stimulus, S₂-imperative stimulus (classic CNV situation), preceding a motor response. The prolongation of the CNV after the motor response is called a postimperative negative variation (PINV).The PINV would appear more helpful in psychiatry than the CNV.² An abnormal PINV is more frequently observed in schizophrenic patients (75%) than in a normal control group (15%).² The present study was designed to investigate the possible influence of age, sex, and length of illness on the recording of the PINV in schizophrenic patients.     

Slow potential correlates of frontal function, psychosis, and negative symptoms

The contingent negative variation (CNV) was used to study cortical activation in frontal and central areas in psychotic and nonpsychotic patients. Psychotic patients showed a higher frontal relative to central CNV amplitude than nonpsychotic patients, a finding that was correlated with performance on a test of frontal function. Negative symptom ratings (physical anhedonia and social closeness) were correlated with relatively low frontal versus central CNV amplitude, but only in psychotic patients.     

Contingent negative variation and attention in schizophrenic and depressed patients

Contingent negative variation (CNV) is supposed to be a psychophysiological indicator of attention and arousal. Both have been reported to be deteriorated in schizophrenic and depressed patients. Thirty-four patients with major depression, 43 patients with schizophrenia and 49 healthy subjects were investigated during acute illness with a complex three-stimulus go/no-go task which requires different states of attention: trials consisted of three complex figures that were tachistoscopically presented. Three identical figures had to be confirmed by pressing a button (target condition). CNV was measured: (1) after the first figure waiting for the second (baseline condition), (2) after two identical figures waiting for the third (response-relevant condition), (3) after two different figures waiting for the third (response-irrelevant condition). The response-relevant condition compared to baseline significantly intensified CNV in healthy controls and to a minor extent in depressed patients but not in schizophrenics. In the response-relevant conditions in healthy controls, CNV was significantly reduced compared to the response-relevant condition. This clear discrimination between response-relevant and response-irrelevant conditions was not observed in either group of patients. Thus, the applied CNV paradigm was able to discriminate schizophrenic and depressed patients from healthy controls. Furthermore, subtle differences between schizophrenic and depressed patients were detected, reflected by the different CNV development across experimental conditions.     

Contingent negative variation and late components of evoked potentials during sleep in man

The aim of this research was to study brain information processing during waking, deep slow sleep (stage IV) and paradoxical sleep (stage V) in humans, by using as a clue endogenous components of the sensory evoked potential, the emitted potential and the contingent negative variation (CNV). Eight subjects underwent three kinds of mixed auditory stimulus couples: (a) SI-SII: 2 identical clicks (50 msec, 5000 Hz); (b) SI-SIII: SIII (50 msec, 500 Hz) different from SI, was during waking, the target stimulus; (c) SI followed by an omitted click. During sleeping, the situation was used without motor response. The contingent negative variation was clearly observed during waking and paradoxical sleep as the evoked potential whose morphology during deep slow sleep was similar to K complexes. The emitted potential was obtained in four subjects out of seven during paradoxical sleep. These results suggest that during wakefulness, the discrimination of an unconditional stimulus involves a conditioning establishment revealed by the CNV and the emitted potential. The fact that the emitted potential and CNV were unavailable during stage IV is an argument in favor of the hypothesis that the conditioning effects disappear during deep slow sleep. The occurrence of CNV and emitted potential during the paradoxical stage of sleep, suggests that a conditioning established during waking can appear during this stage of sleep.     

Pain, anxiety, and contingent negative variation: A clinical and pharmacological study

Contingent negative variation (CNV) behavior was studied in 16 volunteers who were suffering from spontaneous recurrent pain syndromes (idiopathic trigeminal neuralgia, classic migraine). The subjects were divided into two groups, "more anxious" and "less anxious," based on psychometric tests (MMPI and STAI X2). The CNV recordings were carried out, respectively, in basal resting state, during an episode of pain, while under anxiolytic treatment, and lastly, during an episode of pain while under anxiolytic therapy. CNV voltage decrease and frequent appearance of postimperative negative variation (PINV) were observed when pain was present during the recording session. These phenomena were more marked when the pain was accompanied by a greater degree of anxiety. Finally, our results suggest that this slow evoked potential is sensitive to various degrees of anxiety and to pain perception in man, making it useful in the investigation of pain as a complex sensation.     

Slow cortical potential neurofeedback in attention deficit hyperactivity disorder: is there neurophysiological evidence for specific effects?

This study compared changes in quantitative EEG (QEEG) and CNV (contingent negative variation) of children suffering from ADHD treated by SCP (slow cortical potential) neurofeedback (NF) with the effects of group therapy (GT) to separate specific from non-specific neurophysiological effects of NF. Twenty-six children (age: 11.1 ± 1.15 years) diagnosed as having ADHD were assigned to NF (N = 14) or GT (N = 12) training groups. QEEG measures at rest, CNV and behavioral ratings were acquired before and after the trainings and statistically analyzed. For children with ADHD-combined type in the NF group, treatment effects indicated a tendency toward improvement of selected QEEG markers. We could not find the expected improvement of CNV, but CNV reduction was less pronounced in good NF performers. QEEG changes were associated with some behavioral scales. Analyses of subgroups suggested specific influences of SCP training on brain functions. To conclude, SCP neurofeedback improves only selected attentional brain functions as measurable with QEEG at rest or CNV mapping. Effects of neurofeedback including the advantage of NF over GT seem mediated by both specific and non-specific factors. M. Doehnert and D. Brandeis have contributed equally to this paper.     

The Effect of Motor-Response-Deprivation on Contingent Negative Variation (CNV) III: Relation with Maudsley Personality Inventory (MPI)

The contingent negative variation (CNV) was correlated with Maudsley Personality Inventory (MPI) in 43 healthy adults as follows: (1) The conventional CNV with motor-response showed a negative correlation with the scores of extroversion in the MPI (E-scores). The recovery of the conventional CNV after verbal extinction showed both a negative correlation with the E-scores and a positive correlation with the scores of neuroticism (N-scores). (2) The motor-response-deprived CNV in the stimuli and nonresponse sessions (Sa and Na) showed no correlation with the MPI, because they fluctuated according to the subject's attentiveness. On the other hand, the CNV in the discrimination session (Da) with constant attentiveness to stimuli showed a positive correlation with the N-scores. (3) The response times in the control and response sessions showed a positive correlation with the N-scores in males and a negative correlation in females. The correlation with the E-scores was nearly opposite.     

正常成人与抑郁症患者之伴随负变化对照研究

本文使用ＮＩＣＯＬＥＴＣＡ－１０００叠加仪检测２８例符合中国精神疾病分类和诊断标准（ＣＣＭＤ－Ｉ）的抑郁症患者，并与正常成人进行了比较。结果表明抑郁症患者ＣＮＶ波型变异大，平均波幅较对照组降低２９％，最高峰电位降低２０％。且发现抑郁程度愈严重患者的ＣＮＶ波幅愈低，而ＰＩＮＶ时程与对照组之间无显著差异。     

Slow brain potentials and psychomotor retardation in depression

Event-related cortical potentials were recorded in 11 patients with primary depression and 11 healthy control subjects during a serial choice reaction task. Each new trial was voluntarily initiated when the subject pressed a microswitch; an acoustic go or no-go signal followed after a fixed interval. This elicited a Bereitschaftspotential (BP), a contingent negative variation (CNV), acoustically evoked potentials (N1, P2, P3), and a post-imperative negative variation (PINV) in direct succession. These were evaluated conventionally and by principal component analysis (PCA). Patients exhibited significantly longer reaction times and more negative PINVs. BP and CNV did not differ between groups. In conventional amplitude measurement small P3 amplitudes in depressives may be feigned by markedly negative PINVs.     

Abnormalities of the contingent negative variation in Huntington's disease: correlations with clinical features

The contingent negative variation (CNV) is a neurophysiological pattern related to planning of external - paced, voluntary movements. The aim of the study, was to examine the CNV in a cohort of mild demented and non-medicated HD patients, evaluating the CNV amplitude modifications in the light of clinical features and performing Low Resolution Brain Electromagnetic Tomography (LORETA) analysis in order to show the CNV multiple generators. Fourteen HD patients and 25 sex and age-matched controls were studied. All subjects were evaluated by the motor section of UHDRS, MMSE and WAIS. The CNV was recorded by 19 scalp electrodes, with a red light flash as visual warning stimulus (S1), followed by a blue light flash (S2) after a fixed interval of 3 s. The amplitude of early CNV was significantly reduced in HD, compared to controls: the amplitude reduction was significantly correlated with the bradikinesia score. LORETA analysis of early CNV significantly discriminated patients from controls, for a prevalent activation of the posterior part of anterior cingulate cortex in HD. An abnormal activation of the associative cortex devoted to the processing of attention preceding voluntary movement may be supposed in HD, probably mediated by the altered basal ganglia modulation.     

Abnormal contingent negative variation in writer's cramp.

OBJECTIVE: To investigate the physiological abnormality in writer's cramp, a focal dystonia which specifically affects writing. METHODS: We recorded brain potentials that precede hand and neck movements (contingent negative variation or CNV) in 11 patients and 11 age-matched normal subjects. A 1000 Hz tone burst (S1) was delivered to the right or left ear in random sequence, and 2 s after, a 2000 Hz tone burst (S2) was delivered to both ears simultaneously. For the response task to S2, the subjects were instructed to extend their fingers ipsilateral to the ear to which S1 was given in one experiment or to rotate the head to the side of the S1 presentation in another. All the patients had symptoms in the right hand only, and performed both tasks normally. CNV amplitudes were compared between normals and patients using unpaired t test. RESULTS: They showed normal CNV for neck movement but significantly decreased CNV amplitudes for movements both in the affected and unaffected hands. CONCLUSIONS: Our findings suggest that motor programming is specifically abnormal for the affected body part, including the asymptomatic contralateral limb, and that the clinical symptom may result from a deficient compensatory mechanism for abnormal motor programs or subroutines.     

The late event related potentials CNV and PINV in normal and dyslexic subjects

The most prominent ERP to occur during intervals of preparation and anticipation is the contingent negative variation (CNV) or expectancy wave. The resolution of this wave is called the postimperative negative variation (PINV). The purpose of this study was to distinguish the characteristics of the CNV and the PINV in a group of children with reading disabilities or dyslexia and to compare them from a group of normal readers. Nine righthanded boys aged between 10-13 years with reading disabilities were studied. The children were matched with a group of nine normal readers. Four derivations were used: frontal, central, parietal and occipital zones, with reference to linked ears. Data were analyzed using multivariate procedures. Significant differences between groups in CNV amplitude and in PINV amplitude and latency at the left parietal site were observed. We discuss the participation of this zone and we consider processes like expectancy, attention and brain activity signal processing in the differences mentioned.     

Cognitive event-related potentials and reaction time in presenile subjects with initial mild cognitive decline or probable Alzheimer-type dementia

The so-called contingent negative variation (CNV) is a slow brain potential representing a complex of variously overlapped “endogenous” components of behavior related to different reasonably well-known neurocognitive processes. CNV complex evoked with a standard paradigm (S1-2 sec-S2-motor response) and reaction time (RT) to imperative signal (S2) were recorded and measured in 11 patients with initial presenile idiopathic cognitive decline (PICD), 8 with presenile Alzheimer-type dementia (PAD) and 10 healthy age-matched controls. Significant group differences were obtained for measures of some CNV components, particularly of the late pre-S2 CNV. No significant CNV activity, very prolonged RTs and sometimes characteristic post-imperative negative variation (PINV) were observed in the majority of patients with PAD. These results suggest that CNV complex and RT changes similar to those observed in our patients may constitute a valuable clue for the study of pathophysiological brain functioning in the early stages of presenile idiopathic mental deterioration.

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Sommario Scopo della presente ricerca è lo studio mediante metodiche standard di averaging, delle modificazione dell'onda d'aspettativa, sue principali componenti (complesso CNV) e tempo di reazione (RT) delle risposte motorie in pazienti affetti da forme iniziali più o meno gravi di decadimento mentale presenile idiopatico. Sono stati esaminati 19 pazienti (età media: 59.5) e 10 soggetti sani di controllo di pari età (media: 59.6). Otto pazienti presentavano un quadro clinico di demenza presenile di tipo Alzheimer (PAD), mentre in 11 soggetti era stata formulata una diagnosi di possibile forma iniziale presenile di demenza primaria (PICD) poiché non raggiungevano i criteri clinici del DSM-III e del NINCDS-ADRDA Report. Tutti i pazienti sono stati sottoposti preliminarmente and esami clinici, TAC, NMR, EEG con analisi spettrale ed a test psicodiagnostici. Per evocare il complesso CNV-RT si è adottato un parametro di stimolazione molto semplice ed idoneo anche per malati con deterioramento mentale. Oltre all'EOG ed agli RT, l'attività di tipo CNV è stata registrata da regioni frontali, centrali e parietali con referenza bimastoidea. Si sono osservate differenze significative di alcuni componenti fra i gruppi di soggetti esaminati e nella maggioranza dei dementi mancava una vera attività di tipo CNV, gli RT erano enormemente prolungati e sovente si sono registrati caratteristici “post-imperative negative variations” (PINV). I risultati ottenuti confermano l'utilità di queste metodiche nella diagnosi precoce delle demenze primarie presenili.