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PubMed1978

The effect of motor-response-deprivation on contingent negative variation (CNV): the morphology.

Eighty-four healthy subjects (47 males and 37 females) ranging in age between 9 and 76 years were employed in a study of the relations of the CNV morphology with the CNV amplitude, the reaction time and the MPI score. The results were as follows: 1. We classified a new type of Plateau (P) in the negative-going limb (NGL) types. 2. There was no sex difference in the NGL types, but the positive-going limb (PGL) types were influenced by age, and the type II tended to increase between the ages of 40--59 years old. 3. As a whole, the type B in the NGL and the type I in the PGL were most prominent regardless of age, session or paradigm. The type FD was very rare and appeared only in the session N. The types III and IV failed to be found in any healthy subjects. 4. Using the matched control study, the relations of the morphology with the CNV amplitude, the reaction time and the MPI score were analyzed. The conventional CNV amplitude in the sessions C and R increased in the sequences of the types B-A-P and the types I-II, and the CNV amplitudes in the session N increased in the sequences of the types A-B-P and II-I. The reaction time in the sessions C and R tended to prolong in the sequences of the types P-B-A and II-I. With the MPI, as the N-score increased with a decrease of the E-score, the NGL types changed from the type P to A through B in the conventional CNV and from the type A to B or P in the session N, while the PGL types changed from the type I to II in the conventional CNV and from the type II to I in the session N. 5. We suggest that there is a twofold arousal process, specific (task-relevant) and general, behind these types and that the dynamic balance of this process may influence psychological manifestations.

Adolescent↗

PubMed2002

Early contingent negative variation (CNV) shows a small symmetrical negativity in a somatosensory paradigm.

The influence of sensory modulation on the early stage of information processing was investigated with a somatosensory contingent negative variation (CNV) paradigm. Whether or not even a somatosensory input as well as auditory or visual stimulus to one hemisphere elicits the symmetrical "early CNV" was also examined. Eleven normal individuals (3 males, 8 females) performed a conventional CNV paradigm with a click sound as the warning stimulus (WS) and a red light flash as the imperative stimulus (IS). Nine individuals (5 males, 4 females) did the somatosensory CNV paradigm with paired electrical stimuli as WS and IS. The subjects were instructed to press a button in response to IS as fast as possible. The early CNV amplitude was smaller and P300 latency was longer in somatosensory paradigm than conventional paradigm. In addition, the latency of P100 in a somatosensory paradigm was longer than that of N100 in a conventional paradigm. These findings suggest that the initiation of early detection, reflected by P100, the initiation of cognition, reflected by P300, and orienting response, reflected by early CNV, are delayed in a somatosensory CNV paradigm. Furthermore, all event-related potentials (ERPs) evoked by somatosensory stimuli showed a bilateral symmetry.

Adult↗

PubMed2006

Transpupillary thermotherapy for myopic choroidal neovascularization: 1-year follow-up: TTT for myopic CNV.

PURPOSE: To evaluate the use of transpupillary thermotherapy (TTT) for myopic choroidal neovascularization (CNV) retrospectively in a case series. METHODS: Ten consecutive patients with CNV secondary to high myopia were treated with TTT and followed-up for 18.3 +/- 7.1 months (range: 12-30 months). An activity scoring (AS) scheme based on CNV size, central foveal thickness as determined by optical coherence tomography (OCT), amount of subretinal hemorrhage, and fluorescein angiography (FA) staining characteristics was developed to assess the response to treatment. The main outcome measures were AS and visual acuity (VA). RESULTS: There was no significant loss or gain in VA, and the lesions stabilized in all eyes. FA revealed late staining typical of CNV scarring, and the amount of central foveal thickness decreased in all eyes, as determined by OCT. The mean AS at 3, 6, and 12 months and at the final visit were significantly lower than the preoperative AS (P<0.05). No complication occurred during or after treatment. CONCLUSION: A scheme for evaluating overall CNV activity may be useful tool for assessing the response of patients to TTT. TTT seems to stabilize myopic CNVs both clinically and as revealed by angiography, with a significant decrease in the activity of lesions. Longer term results are required to evaluate the stabilizing effect of TTT in myopic CNV.

Adult↗

PubMed1975

The frontal CNV: its dissimilarity to CNVs recorded from other sites.

Two new techniques were used to study the distribution of the CNV recorded from the scalp of humans. One technique was for the suppression of eye movements and the elimination of them fron the average data. The other technique was for the recognition of differences in the form of CNVs recorded from different sites. The latter technique utilized an average vertex CNV as a template pattern against which CNVs from the vertex, left and right frontal, central and parietal sites were matched. The results showed that the frontal CNV was different in form from the vertex, central and parietal Cnvs and that the vertex, central and parietal CnvS were similar in form. An analysis of the amplitudes of CNVs showed that the frontal CNVs were significantly smaller than the CNVs from all other sites, that the vertex CNV was significantly larger than the parietal or central CNVs and that the central CNV was significantly larger than the parietal CNV. There were no differences in amplitude between hemispheres within Condition A responding with the right hand) or Condition B (responding with the left hand) or between Conditions A and B. The results are discussed with respect to their possible theoretical implications.

Adult↗

PubMed1987

Complex event-related potentials (P300 and CNV) and MSLT in the assessment of excessive daytime sleepiness in narcolepsy-cataplexy.

The P300 and contingent negative variation (CNV) evoked potential (EP) paradigms were performed by 12 untreated narcoleptics and controls immediately prior to each nap of the Multiple Sleep Latency Test (MSLT) in order to assess whether they might hold promise as rapid quantitative techniques to assess excessive daytime sleepiness. The Stanford Sleepiness Scale (SSS) was also completed across test days and immediately before and after both the evoked potential recordings and MSLT naps. MSLT findings confirmed shorter sleep latencies and frequent SOREMPs in narcoleptics and a strong mid-afternoon increase in sleepiness based upon pressure for NREM sleep in both groups. On SSS narcoleptics were sleepier and they showed greater increase in sleepiness induced by the EP tests and greater sleepiness reduction by the MSLT naps. In the P300 paradigm, narcoleptics showed smaller component P3 amplitudes and larger P1 amplitudes. In the CNV paradigm, N1 latencies were greater in narcoleptics to both S1 and S2 and the post-CNV negative component was larger: but no significant differences were seen for the main CNV measures of negativity amplitude in the first or second halves of the response. The P300 paradigm but not the CNV, therefore, appeared to be a sensitive EP measure of sleepiness. Finally, EP components in both the P300 and CNV paradigms showed time-of-day (circadian) differences between narcoleptics and controls.

Acoustic Stimulation↗

PubMed1986

The contingent negative variation (CNV) to fear-related stimuli in acquisition and extinction.

Contingent Negative Variation (CNV) in anticipation of phobic and neutral slide material was recorded in Acquisition of a learned association between tone pitch and slide type, and in Extinction (following removal of slide presentation). In phobic volunteers, no clear CNV differentiation between 'phobic' and control condition was apparent in either Acquisition or Extinction. For Control subjects, a different pattern entirely has been demonstrated, with anticipation of the neutral condition giving rise to a larger CNV than anticipation of the 'phobic' condition (in Acquisition). In addition, Extinction led to a reversal of this CNV amplitude relationship, with the tone previously associated with the phobic slide producing a DC-shift which was larger than that following the tone previously paired with the neutral slide. The results are compatible with a dynamic model of CNV generation according to which CNV amplitude is positively related to an expectancy for reward or non-punishment but inversely related to an expectancy for punishment or non-reward.

Adult↗

PubMedDate not supplied

Effects of smoking and telic/paratelic dominance on the contingent negative variation (CNV).

Concepts from reversal theory, a general theory of motivation, emotion and action, have recently been shown to be relevant to smoking behavior and smoking cessation. One relevant concept is that of telic and paratelic dominance. Individuals who are paratelic-dominant are playful, spontaneous, and prefer high arousal seeking. Those who are telic-dominant are serious, tend to plan ahead, and prefer low arousal. This led to the hypothesis that smoking might increase the amplitude of the contingent negative variation (CNV) in paratelic-dominant smokers more than in telic-dominant smokers. CNV was obtained using a Go/NoGo reaction time task with a 2 s S1-S2 interval and variable intertrial intervals. S1 indicated whether the subject was to respond to S2 or not. Errors were punished with a burst of white noise. Subjects performed the CNV task three times: after being deprived of smoking for at least 4 h; after sham smoking; and after smoking a cigarette of their own brand. Telic-dominant subjects differed from paratelic-dominant subjects in the relative amplitude of early (1 s) and late (2 s) components of the CNV. Smoking did not differentially affect the dominance groups unless gender was taken into account, and the most striking interactions between smoking and dominance groups were noted for the NoGo trials. As expected, smoking decreased the amplitude of the early component of the NoGo CNV for telic-dominant women, but increased it for paratelic-dominant women; no significant differences were found for the late component. In men, smoking increased the late CNV more for telics than for paratelics, while smoking did not differentially affect the early component.

Acoustic Stimulation↗

PubMed1998

Topographic differences in CNV amplitude reflect different preparatory processes.

Topographic differences in Contingent Negative Variation (CNV) were recorded while people were preparing for cognitive versus motor tasks in an S1-S2 paradigm. CNV had a frontal distribution when people prepared to encode words into long-term memory, whereas CNV was more centrally distributed when the tasks were predominantly motoric. These topographic differences appeared to be related to the type of task rather than the amount of information extracted from the S2, because a direct manipulation of the level of S2 processing had little effect on CNV amplitude. The topographic differences in CNV suggest that preparation for motor activity is a different psychological process from preparation for stimulus processing and that these two processes are subserved by different neural structures. This experiment also demonstrated that a recognition memory paradigm can be useful in the investigation of the psychological correlates of CNV.

Adolescent↗

PubMedDate not supplied

[Comparative study of the CNV and the quantitative EEG during a simple motor task (author's transl)].

The purpose of this study was to evaluate CNV amplitude variability and its degree of covariance with the spontaneous EEG (quantified by FFT algorithm) and the reaction time. 14 healthy male subjects made from atypical for one hour, and they had to keep their eyes closed. Recordings were during this period. CNV experimental paradigm was performed (S1--S2 = 1500 msec). The major findings of this study were that: 1) the CNV amplitude progressively decreased during the first part of the test (habituation) and then tended to stabilize. While not correlated with the vigilance index of spontaneous EEG (alpha/theta + delta index) the CNV amplitude was significantly related to the alpha reactivity index (% alpha of spontaneous EEG--% alpha of the S1--S2 EEG), 2) the CNV slope (calculated by drawing two points situated at 600 msec and 1400 msec after S1) showed significant relationship to both these EEG indices and the reaction time. These data are discussed in terms of Cooper's distinction between "scopeutic" and "categoric" processes (1978) and in terms of the Tecce model of the CNV (1972).

Adult↗

PubMed1984

[Is there a correlation between the phases of CNV and the power spectrum of the EEG?].

In 14 volunteers, the relationships between CNV and EEG power spectrum were studied during 3 periods of 1 sec: before S1, between S1 and S2, and after S2. We noted first a relation between CNV amplitude and EEG spectrum over the 3 periods: there was an inverse correlation for the alpha band, and a direct correlation for the beta band. We also observed a direct, strong correlation (r = 0.94) between CNV slope and alpha band reactivity during the S1-S2 interval, but this held only for subjects showing a decrease of alpha activity during the S1-S2 interval. There was no correlation at all between the positive phase (post-S2) of the CNV and EEG. These results are discussed in terms of functional states of the brain influencing CNV development, as well of the various modes of activation and reactivity at the individual level that modify the relationships between CNV and EEG.

Adolescent↗

PubMed2001

The Swedish national survey of surgical excision for submacular choroidal neovascularization (CNV).

PURPOSE: To compare the visual outcome after surgical removal of subfoveal choroidal neovascularization (CNV) in patients younger and older than 50 years of age. METHODS: Patient records from all Swedish centers performing submacular CNV surgery were reviewed and 90 patients treated between 1992-1999 with a follow-up of 6 months or more were included. The results obtained in 49 patients aged 51-89 years (median=72 years) with neovascular disease caused by age-related macular degeneration (AMD) were compared with the outcome of 41 patients aged 6-49 years (median=36 years) with CNV secondary to non-AMD causes. The main outcome measure was the improvement or deterioration in visual acuity (standardized in logMAR units) at 6 months following surgery. Secondary endpoints were recurrent CNV and surgical complications. RESULTS: The level of preoperative visual acuity was not significantly different between younger patients with CNV associated with non-AMD and older patients with visual loss due to AMD (p=0.069). However, visual acuity at 6 months after surgery was better (p=0.0042) in younger patients (median improvement=0.19 logMAR) than in older patients (median improvement=0.0 log MAR). Marked visual improvement (>1 log MAR unit) was seen in 29% of non-AMD patients <50 years compared to 0% in the AMD group >50 years. CONCLUSION: Surgical removal of submacular CNV does not appear to improve visual acuity in patients > 50 years of age. However, it may be beneficial for younger patients where a substantial improvement of visual acuity is seen in a subset of these patients. Further studies are required to assess the long-term outcome.

Adolescent↗

PubMed2006

EIAV vector-mediated delivery of endostatin or angiostatin inhibits angiogenesis and vascular hyperpermeability in experimental CNV.

We evaluated the efficacy of equine infectious anaemia virus (EIAV)-based lentiviral vectors encoding endostatin (EIAV.endostatin) or angiostatin (EIAV.angiostatin) in inhibiting angiogenesis and vascular hyperpermeability in the laser-induced model of choroidal neovascularisation (CNV). Equine infectious anaemia virus.endostatin, EIAV.angiostatin or control (EIAV.null) vectors were administered into the subretinal space of C57Bl/6J mice. Two weeks after laser injury CNV areas and the degree of vascular hyperpermeability were measured by image analysis of in vivo fluorescein angiograms. Compared with EIAV.null-injected eyes, EIAV.endostatin resulted in a 59.5% (P<0.001) reduction in CNV area and a reduction in hyperpermeability of 25.6% (P<0.05). Equine infectious anaemia virus.angiostatin resulted in a 50.0% (P<0.05) reduction in CNV area and a 23.9% (P<0.05) reduction in hyperpermeability. Equine infectious anaemia virus.endostatin, but not EIAV.angiostatin significantly augmented the frequency of apoptosis within the induced CNV as compared with injected controls. TdT-dUTP terminal nick end labeling analysis 5 weeks post-injection, and histological and retinal flatmount analysis 12 months post-injection revealed no evidence of vector- or transgene expression-related deleterious effects on neurosensory retinal cells, or mature retinal vasculature in non-lasered eyes. Highly expressing EIAV-based vectors encoding endostatin or angiostatin effectively control angiogenesis and hyperpermeability in experimental CNV without long-term deleterious effects, supporting the use of such a strategy in the management of patients with exudative age-related macular degeneration.

Angiogenesis Inhibitors↗

PubMed2000

[Radiotherapy for choroidal neovascularization (CNV) in age-related macular degeneration (AMD)].

AIM OF THE STUDY: Several pilot studies have indicated, that radiation therapy might have a beneficial effect on the course of CNV in AMD. This controlled study was aimed at the question, whether such treatment might halt progression of neovascular AMD and whether a low or a high radiation dose should be applied. METHODS AND PATIENTS: Enclosed were patients aged > or = 60 and < or = 85 and eyes with a VA of > or = 0.1 and < or = 0.6, revealing a juxta/subfoveal CNV either of the occult or the classic type. Treatment was performed with a linear accelerator at fractions of 2 Gy up to a total dose of 10 Gy or 36 Gy. 95 eyes had completed follow-up of > or = 12 < or = 24 months. RESULTS: Among eyes with occult CNV 8 received 36 Gy, 16 were treated with 10 Gy and 21 were in the control group. Mean visual loss was 3.5 lines after 12 months and 5 lines after 24 months with no difference between irradiated eyes and those in the control group. In the groups with classic CNV 8 eyes were treated with 36 Gy, 27 eyes received 10 Gy and 15 eyes were in the control group. Mean visual loss after 6 months was 2.2 lines in eyes of both groups treated with radiation and 5.7 lines in the control group. This was statistically significant (p < 0.05). VA was < 0.1 after 12 (24) months of follow-up in 50 (75)% of the cases with 36 Gy, in 48 (83)% with 10 Gy and in 60 (83)% of the controls. These results were statistically significant after 12 months only. DISCUSSION AND CONCLUSIONS: The natural course of occult CNV could not be improved by irradiation with 10 or 36 Gy. In eyes with classic CNV a VA of > or = 0.1 was maintained significantly more often in irradiated eyes than in those of the control group. Treatment with 36 Gy however was associated with an unacceptable incidence of radiation retinopathy.

Aged↗

PubMed2006

[Status of TTT in the therapy for CNV].

Transpupillary thermotherapy (TTT) and photodynamic therapy (PDT) are recent treatment options for choroidal neovascularisation (CNV). In PDT a photochemical reaction is induced by the injection of a photosensitising substance. In contrast to this, TTT is a non-invasive photothermal treatment option for CNV and choroidal tumours. It leads to a low-grade-hyperthermia with consecutive induction of metabolic processes and production of heat-shock proteins in order to restore cellular homeostasis. Classical laser coagulation as recommended by the Macular Photocoagulation Study Group produces a photocoagulative effect with significant tissue hyperthermia and prompt visual loss. For classic CNV, PDT represents an established therapy option. Positive results of the treatment of occult CNV by PDT have enlarged the use of PDT to this kind of CNV. TTT represents an economic therapy modality for (mainly) occult CNV. The effect for visual outcome varies in different studies. The results are shown in a .

Choroidal Neovascularization↗

PubMed1980

Age differences in the contingent negative variation (CNV): reduced frontal activity in the elderly.

The effects of distraction on the contingent negative variation (CNV) were investigated in a group of 11 elderly (mean = 72.2 years) and a group of 12 young (mean = 23.3 years) subjects. Scalp electrical activity was recorded from midline sites at frontal, central, and parietal locations. Three experimental conditions included Recall, No Recall, and Control situations. In the Recall, or distraction condition, spoken consonant-vowel-consonant (CVC) letters were presented concurrently with the CNV signal interval and were recalled by the subjects after each trial. The No Recall condition was similar to the Recall task except that subjects were not required to repeat the CVSs. The Control condition presented a standard S1 - S2 CNV situation without CVCs. Amplitudes of the CNV, reaction times (RTs), and heart rate (HR) served as indices of distraction. The effects of distraction for both age groups indicated reduced CNVs, lengthened RTs, and elevated HRs. However, a significant age by electrode interaction revealed that while CNV amplitudes at central and parietal sites were comparable between age groups, amplitudes at the frontal placement were consistently reduced in the elderly compared to the young in all conditions. The finding of diminished frontal activity, as measured by the CNV, suggests a process of selective cortical aging and possible cellular loss which may be linked to performance deficits.

Adult↗

PubMed1982

Melancholia and excessive CNV recovery after nonresponse condition.

The effect of nonresponse on the Cz-CNV recovery was studied in 13 depressed patients on the hypothesis that the excessive CNV recovery had a relation to melancholia. The depressed patients had a significantly small Control CNV area before the nonresponse as compared with a matched group of healthy controls. The dysthymic patients by the Maudsley Personality Inventory (MPI) showed a significantly smaller Control CNV area than the non-dysthymic patients. Melancholic patients who met the DSM-III criteria had a significantly longer control reaction time and more excessive CNV recovery than the non-melancholics. The excessive CNV recovery is useful as a predictor for melancholia, and the motivational facilitation and preparatory motor inhibition underlying the psychomotor retardation and hence "endogenous process" were discussed.

Adult↗

PubMed1997

Effects of reduction in arousal level caused by long-lasting task on CNV.

The present study aimed at investigating an inverted-U relationship between contingent negative variation (CNV) and arousal level by examining the effects on CNV of gradually reduced arousal level by long-lasting task. The subjects conducted a simple reaction time task consisting of warning stimuli (S1) and imperative stimuli (S2). This task consisted of 200 trials and lasted about 40 minutes. During this task, spontaneous EEG before S1 and SPL (skin potential level) were measured as indicators for arousal level. The 200 CNV, EEG and SPL data were classified into 5 blocks each of which included 40 trials of data. Analysis was made in seven subjects in whom reduction in the arousal level in long-lasting task was shown by increase in the relative power values of alpha waves before S1 and decrease in the SPL. As a result, the amplitude of early CNV at Fz was observed to increase from the earlier half phase (block 1) to the middle phase (block 3) and to decrease from the middle phase (block 3) to the latter half (block 5). In the middle phase, the amplitude was the greatest. The low amplitude of early CNV in the early half of the task (block 1) was inferred to have been induced by excessive arousal state because of the low relative power values of alpha waves and the high SPL at this time. On the other hand, the low amplitude in the later phase (block 5) was inferred to have been induced by reduction in arousal level because of the high relative power values of alpha waves and the low SPL. These results suggested that CNV amplitude and arousal level was in an inverted-U relationship.

Adult↗

PubMed2000

Task related changes in contingent negative variation (CNV) response of endogenous evoked potentials.

Contingent negative variation (CNV) is a slow negative cortical potential shift, which occurs during a warned foreperiod reaction time paradigm. Most studies of evoked potentials have concentrated on components occurring during the first 300 msec, although there are important and recordable aspects of signal processing occurring well beyond 300 msec e.g. late negative slow wave. CNV has proven sensitive to a number of psychological variables, none of which can yet be singled out as a definitive or exclusive correlate. Changes are expected if measured after a rigorous mental exercise. CNV was measured in 20 normal male subjects aged between 18 and 20 years. CNV was recorded twice in each subject before and after the administration of a mental task. The auditory mental task comprised repeating in reverse order string of random digits read out to the subject at a uniform speed of 1 per second. The visual mental task comprised reading laterally inverted type written text. Each subject had to undergo 2 sessions in separate sittings. The latency and amplitude of waves N1, P3, orientation (O), expectancy (E), CNV, reaction time (RT) were recorded. These values recorded before and after the task were compared statistically using student's unpaired t-test. The significant latencies recorded before and after the auditory task were, N1: 88.00 +/- 11.96 and 100.00 +/- 21.52 msec, P3: 289.00 +/- 54.85 and 299.00 +/- 52.91 msec, reaction time (RT): 102 +/- 17.05 msec and 123 +/- 17.5 msec, and in case of visual task, N1: 88 +/- 13.16 msec and 99.00 +/- 16.51 msec, reaction time (RT): 107 +/- 11.74 msec and 127 +/- 13.42 msec respectively. All other CNV wave latencies and amplitude changes were insignificant. Hence task effects sensory perception as reflected by increased latency of the long latency response N1 and the cortical integrative processes resulting in increased reaction time.

Adolescent↗