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.     

Time-dependent post-imperative negative variation indicates adaptation and problem solving in migraine patients

According to the Seligman theory of learned helplessness, depression is caused by a repetitive experience of loss of control resulting in internal, stable and global attributional styles for negative events. In depressed patients and healthy controls experiencing such events, an increased amplitude of the post-imperative negative variation (PINV) has been described. The aim of the study was to investigate a possible correlation between migraine, depression, learned helplessness and PINV. 24 patients suffering from migraine without aura and 24 healthy controls were exposed to a situation of loss of control whilst the contingent negative variation (CNV) from C3, C4 and Cz were recorded. Before conducting the experiment, the subjects were asked to answer the Beck Depression Inventory (BDI) and the German attributional style questionnaire (GASQ). Amplitudes of total CNV, early and late component and PINV were calculated in eight blocks of four recordings each. The results confirm findings of a pronounced PINV in situations of loss of control, though high amplitudes were not correlated with low values in the GASQ and therefore with learned helplessness. High PINV in migraine patients correlated with high scores in the BDI and the list of the complaints questionnaire. However, this was not the case in healthy controls. In this experimental situation, PINV in migraine patients can be interpreted as an expectancy potential in order to avoid failure and helplessness.     

Characteristics of the contingent negative variation in patients suffering from specific phobias.

The essential clinical feature of phobic neurosis is the anticipatory fear of certain objects and situations. Since an important factor in the generation of the contingent negative variation (CNV) is the anticipation of the imperative stimulus, records of CNVs were used as an indicator of electrocortical activity in a group of 14 patients suffering from specific phobias. After clinical evaluation, a CNV to a picture of a nondisturbing object was obtained. The amplitude of the CNV and duration of the PINV (postimperative negative variation) were taken as reference values against which response to the phobic objects were evaluated. Reaction time was automatically measured between the period of S2 and the button press. Significant differences, viz., larger CNV amplitude, longer PINV duration, and shorter reaction time, were found with phobogenic than with nondisturbing stimuli. After behavioral recovery with behavior therapy, no differences were noted in the CNVs obtained with the presentation of non-disturbing and the ones that were phobogenic stimuli. The significance of the results for an understanding of phobic neurosis and behavior therapy are discussed.     

Comparative study of the amplitude, surface and duration of the pre- and post-imperative waves of the CNV (contingent negative variation) in a group of 40 schizophrenic and schizo-affective patients as compared with normal subjects

In 27 normal adult subjects, pre- and postimperative phases of the CNV had an homogeneous pattern. The return to the baseline was of short duration (320 +/- 170 msec) whatever the amplitude and surface. This is in favor of an active mechanism terminating the CNV. In 27 schizophrenic and 13 schizoaffective patients, pre- and postimperative phases of the CNV were heterogeneous in character suggesting the possibility of multiple disturbances. When present, the preimperative negativity was of lower amplitude and had a delayed return to the baseline with a wider dispersion. In the patients with preimperative negativity followed by a PINV (postimperative negative variation), a linear relationship has been found between the amplitudes of the two waves.     

Contingent negative variation in adults with Gilles de la Tourette syndrome.

Three deflections or waves of the Contingent Negative Variation (CNV): the Slow Negative Wave (SNW), the Terminal CNV (TCNV) and the Post Imperative Negative Variation (PINV) were studied in 18 adults with Gilles de la Tourette syndrome and in 15 controls. The patients showed a reduced SNW, a normal TCNV and an increased PINV. Moreover, at the right parietal region the patients demonstrated a decreased SNW, TCNV and PINV. The results are discussed in relation to behavioral and neuropsychological disturbances found in Gilles de la Tourette syndrome.     

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.     

Parkinson disease: electrophysiological (CNV) analysis related to pharmacological treatment

The contingent negative variation (CNV) was studied in a group of patients with Parkinson's disease. Testing was carried out 3 times: after a pharmacological wash-out period and at 15 and 30 days after the start of treatment with L-DOPA and bromocriptine. Peak and area CNV increased significantly after each treatment. The post-imperative negative variation (PINV) was observed in 6 out of 10 patients. The correlation found between electrophysiological functioning (CNV) measures and pharmacological treatment supports the view that dopaminergic brain activity mediates the generation of the slow negative event-related brain potentials.     

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.     

Effects of serial visuomotor tasks on contingent negative variation

We evaluated contingent negative variation (CNV) in 15 right-handed normal subjects who performed simple finger extension(NB) or skilled finger movement task with visual guidance (B). When subjects performed serial tasks of NB-B1 (first block of B)-B2 (second block of B), the CNV amplitudes were larger in BI compared with NB at the left frontoparietal leads for early CNV, at widely distributed areas for the middle CNV and at the left frontopatietal and right frontal leads for late CNV. The present results suggest that the frontoparietal area involving the prefrontal and sensorimotor cortices, plays an important role in visuomotor learning.     

Postimperative negative variation and skin conductance response in chronic DSM-III-R schizophrenia.

The hypothesis was tested that there are relationships between schizophrenic negative or deficit symptoms, the skin conductance nonresponding and an elevated amplitude of the postimperative negative variation (PINV). These variables were recorded in 16 chronic schizophrenics and 10 healthy controls. Clinical symptoms were assessed by the Brief Psychiatric Rating Scale, Scale for the Assessment of Negative Symptoms, Frankfurt Complaint Questionnaire 3 and Chapman Questionnaire. In the patient group we found a significantly elevated PINV at Fz. Surprisingly, only one patient was a skin conductance nonresponder. PINV amplitude at Fz and the number of skin conductance responses to habituation were not correlated with negative or deficit symptoms inclding anhedonia. The hypothesis thus had to be rejected.     

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.     

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.     

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.     

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.     

军人创伤后应激障碍患者的关联性负变异常变化及临床随访

目的　了解军人创伤后应激障碍 (PTSD)患者关联性负变 (CNV)的特征和治疗缓解后CNV的变化。方法　应用美国NicoletBravo型脑诱发电位仪及光、声两种成对刺激方法 ,对 6 6例发病期PTSD患者 (患者组 )和 5 6名健康军人 (对照组 )进行CNV测定以及症状自评量表 (SCL - 90 )和事件影响量表 (IES)评定 ,并对患者组中的 6 0例进行了临床随访。结果　患者组发病期M1潜伏期延迟 (P <0 0 1) ,M2 波幅增高 (P <0 0 1) ,命令信号后负变化(PINV)出现率增高 (P <0 0 1) ;SCL - 90及IES总分及其部分因子分升高 (P <0 0 1) ;CNV变异指标与SCL - 90及IES总分及其部分因子分显著相关 (P <0 0 1或 0 0 5 )。患者组康复期M1潜伏期、M2 波幅和PINV出现率 ,以及SCL- 90与IES总分及其部分因子分均恢复至正常值内 (与发病期比较P <0 0 1,与对照组比较P >0 0 5 ) ,且治疗前后CNV变异指标差值与精神症状减分率显著相关 (P <0 0 1或 0 0 5 )。结论　PTSD患者的CNV变化可能是状态标志。     

网络游戏成瘾青少年事件相关电位关联性负变的实验研究

目的研究网络游戏成瘾青少年事件相关电位中关联性负变(CNV)的变化特点。方法使用德国BP公司Brain AmpDC型64导事件相关电位工作站,采用经典的CNV实验模式,记录30例青少年的CNV波形,其中网络游戏成瘾组15例和正常对照组15例,脑电分析后比较两组CNV差异。结果网络游戏成瘾组的CNV波形欠规则,与正常对照组进行比较,CNV潜伏期A点延迟(P0.05),CNV平均波幅和命令后伴随负电位(PINV)平均波幅均显著降低(P0.05)。结论网络游戏成瘾青少年CNV的变异特点为网络游戏成瘾青少年病人的发病机制提供一些线索,并为其明确诊断提供了脑电生理依据。     

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.     

Topographic CNV activity mapping, presenile mild primary cognitive decline and Alzheimer-type dementia.

The CNV complex evoked with a standard paradigm (S1-2 sec-S2-motor response) and reaction time (RT) to the imperative signal (S2) were recorded and measured in 12 patients with initial presenile idiopathic cognitive decline (PICD), 12 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 variations (PINV) were observed in the majority of patients with PAD. These results suggest that similar CNV complex and RT changes to those observed in our patients may constitute a valuable clue in the study of pathophysiological brain functioning in the early stages of presenile idiopathic mental deterioration.     

Impaired modulation of the saccadic contingent negative variation preceding antisaccades in schizophrenia.

BACKGROUND: The contingent negative variation (CNV) is considered to reflect prefrontal functioning and can be observed before manual and ocular motor responses. Schizophrenic patients exhibit reduced CNV amplitudes in tasks requiring manual motor responses. A number of studies has also found normal prosaccades, but delayed antisaccades and an augmented rate of erroneous prosaccades during the antisaccade task in schizophrenia. In this study we examined the CNV during pro- and antisaccade tasks in schizophrenic patients and healthy control subjects. METHODS: Data of 17 medicated schizophrenics (ICD-10, F20) and 18 control subjects, matched with patients for age, gender, and education were analyzed. Horizontal pro- and antisaccades were elicited in four blocks, each consisting of 80 trials. Electroencephalogram was recorded from 32 channels with a DC amplifier. RESULTS: Patients exhibited delayed correct responses and more erroneous prosaccades during the antisaccade task than control subjects, but normal prosaccadic reaction times. In control subjects, the vertex-predominant saccadic CNV was generally larger than in patients, and larger during the anti- than during the prosaccade task. This task-related amplitude augmentation was absent in patients. Analyses of additional components suggested specificity of impaired event-related potential modulation to the saccadic CNV. CONCLUSIONS: In accordance with the presumed prefrontal dysfunction, our results suggest deficient preparation and execution of antisaccades in schizophrenia.     

Relative contribution of antipsychotics,negative symptoms and executive functions to social functioning in stable schizophrenia

The purpose of this study was to examine the relative contributions of antipsychotic medication, negative symptoms and executive functions to impairment in social functioning in a sample of outpatients with stable schizophrenia.