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PubMed1978

[Studies of the expectancy wave (CNV) in patients with interruption of the thalamo-prefrontal interconnnection pathways caused by psychosurgical prefrontal lobotomy operations].

Frontal and vertex CNVs were studied in 8 selected nonschizophrenic patients subjected to unilateral or bilateral extensive prefrontal lobotomy. The dorsomedial thalamo-frontal pathways had been severed and their regeneration must be considered impossible. Standard CNV task (S1-S2-R) was followed in order to elicit CNVs from the frontal areas anterior to the line of sections and at Cz. In 7 out of 8 patients it was quite easy to evoke CNV with almost normal features and equal latencies in each case from all the cortical areas explored. These results show that CNV formation is not grossly altered in the prefrontal areas which have been irreversibly deprived of normal bi-directional mediothalamic-frontocortical connnections. This suggests that the role of the dorsomedial thalamo-frontal pathways are not essential in the genesis of the frontal CNV in humans. These findings would suggest that the CNV is a diffuse electrical event essentially related to a unitary cerebral process mediated fundamentally by nonspecific ascending meso-diencephalic reticular systems. The differences in morphology and polarity of the CNVs detectable in various brain structures are presumably related to their intrinsic anatomo-functional characteristics and to the method commonly utilized in recording the CNV.

Adult↗
PubMed2001

Retina-sparing laser treatment of occult CNV by vitrectomy and localised detachment of the macula.

BACKGROUND: Occult choroidal neovascularisation (CNV) was treated by a novel surgical approach. In order to spare the retina during laser photocoagulation of occult CNV, the retina was detached by subretinal infusion of a ringer solution. After localised detachment of the neural retina the CNV was transretinally coagulated by an endoprobe of a diode laser. METHODS: Twelve patients with occult CNV were treated in such a way. The mean duration of follow-up was 3.5 +/- 1.6 months. After 4 weeks fluorescein angiography and indocyanine green angiography were performed in all patients. Laser exposure time was 1.1 +/- 0.7 s and laser energy was 1.2 +/- 0.7 W. RESULTS: In 10 of 12 patients the retina could be successfully detached and performed. In all cases the retina remained unchanged during laser photocoagulation. After 5 days subtle RPE atrophy and after 1 month obvious RPE atrophy was found. After 4 weeks, in 8 of 10 cases the CNV was completely occluded and no late leakage was found. Three months after operation, retinal atrophy could be seen in all cases. Visual acuity was lower in 6 and unchanged in 4 of 10 patients. CONCLUSION: Despite acute sparing of the neural retina the long-term effects are not better than after conventional laser photocoagulation, because secondary atrophy of the retina develops.

Aged↗
PubMed1979

A CNV rebound effect.

Fifty normal volunteers were tested in two conditions: (1) a constant-foreperiod reaction time situation consisting of a flash-tone-key press sequence (control trials); (2) a '50%-letters' condition, in which two types of trials occurred randomly--no letters trials, which were identical to control trials, and letters trials, which were similar to control trials but also involved the presentation of four auditory letters within the flash-tone interval as part of a short-term memory task. Compared to control trials, CNV amplitude showed a pattern of reduction in letters trials accompanied by slower reaction times to tone (CNV distraction effect). Compared to control trials, CNV amplitude showed an unexpected supranormal increase in no-letters trials. The CNV rebound effect observed in no-letters trials was interpreted as reflecting a switching of attention from the divided attention set intrinsic to letters trials (listening for letters and preparing for response to tone) to an undivided attention set in no-letters trials (simply preparing for response to tone). The CNV rebound effect, which is diminished in aging individuals and absent in psychosurgery patients, appears to represent a non-invasive technique of possible value in assessing pathophysiology of human brain functioning.

Adult↗
PubMed1993

The 'oddball CNV' as an indicator of different information processing in patients with panic disorders.

In previous studies we found an inverse relationship between CNV amplitude and the probability of the occurrence of the warning stimulus (S1) in a cued reaction time task. The aim of the present study was to investigate this 'oddball effect' on CNV amplitude (Oddball CNV) in patients with anxiety disorders, since this effect describes the influence of event probability on reactive as well as proactive components of information processing. Patients suffering from panic disorders with or without agoraphobia and controls participated in a choice reaction time experiment. The subjects' task was to respond to flashes (S2s), cued 4 s in advance in random order by one of two easily distinguishable acoustic stimuli (S1a, S1b). In condition 1 the probability of S1a and S1b was 0.2 and 0.8, respectively, and in condition 2 0.5 for both S1s. The DC-EEG was recorded from F3, F4, C3, Cz, C4 and P3, linked mastoids as the reference. The data obtained confirm the oddball effect on the CNV amplitude, show clear deviations of patients in this effect, and also indicate remarkable differences in CNV shape between patients and controls. These observations are discussed as differences in information processing and information utilization.

Adult↗
PubMed1994

Contingent negative variation (CNV) and erotic preference in self-declared homosexuals and in child sex offenders.

Contingent negative variation (CNV) was recorded bilaterally from central electrodes using a "match/mismatch" paradigm in (Study 1) samples of heterosexual men (N = 6), gay men (N = 10) and lesbian women (N = 14) and (Study 2) in samples of child sex offenders (N = 34) and heterosexual control men (N = 19). Sexual orientation was assessed using the Multidimensional Scale of Sexuality (MSS) and the Human Sexuality Questionnaire (HSQ). Separate CNV averages were formed for each condition of stimulation: for Study 1, slides of adult male and female nudes; for Study 2, slides of child, pubescent and adult male and female nudes. Penile plethysmographic (PPG) data were also obtained from 15 of the child sex offender sample while they viewed stimuli of the same categories as were used in the CNV recording. On the basis of their PPG responses to children, child sex offenders were classified as either "pedophiles" or "non-pedophiles". In Study 1 significant Group x Sex (of slide) and Group x Electrode interactions indicated that: (i) heterosexual men (but neither homosexual group) showed significantly larger CNVs to female than to male slides; (ii) both homosexual groups showed significantly asymmetrical (R > L) CNVs. In Study 2, controls showed significantly greater CNVs to adult females than to both adult males and female children. Child sex offenders showed no significant differences in CNV to male and female slides for any age. "Non-pedophiles" showed significantly larger CNVs to female adults than to female children, but "pedophiles" did not. It is concluded that CNV has promise as a measure of both deviant and non-deviant sexual preference.

Adolescent↗
PubMed2006

Kinesthetic but not visual imagery assists in normalizing the CNV in Parkinson's disease.

OBJECTIVE: This study investigated whether kinesthetic and/or visual imagery could alter the contingent negative variation (CNV) for patients with Parkinson's disease (PD). METHODS: The CNV was recorded in six patients with PD and seven controls before and after a 10min block of imagery. There were two types of imagery employed: kinesthetic and visual, which were evaluated on separate days. RESULTS: The global field power (GFP) of the late CNV did not change after the visual imagery for either group, nor was there a significant difference between the groups. In contrast, kinesthetic imagery resulted in significant group differences pre-, versus post-imagery GFPs, which was not present prior to performing the kinesthetic imagery task. In patients with PD, the CNV amplitudes post-, relative to pre-kinesthetic imagery, increased over the dorsolateral prefrontal regions and decreased in the ipsilateral parietal regions. There were no such changes in controls. CONCLUSIONS: A 10-min session of kinesthetic imagery enhanced the GFP amplitude of the late CNV for patients but not for controls. SIGNIFICANCE: While the study needs to be replicated with a greater number of participants, the results suggest that kinesthetic imagery may be a promising tool for investigations into motor changes, and may potentially be employed therapeutically, in patients with Parkinson's disease.

Aged↗
PubMed1998

Effects of distracting stimuli on CNV amplitude and reaction time.

The present study investigated the reliability of CNV distraction and rebound effects, and their relation with reaction time. Twenty-four subjects were presented three blocks of trials: (1) a control block--a fixed foreperiod reaction time task consisting of a flash-tone-key press sequence; (2) a divided-attention block--randomly intermixed trials with and without a short-term memory task (three visually-presented letters) in the S1-S2 interval (50% of each); and (3) a second control block. In trials with the short-term memory task, subjects recalled the letters after the key press to the tone. Compared to the control block, CNV amplitudes during trials with letters were significantly smaller and reaction times to S2 were significantly slower (distraction effect). In contrast, CNV amplitudes during trials with no-letters were significantly larger (CNV rebound), but the reaction times were again significantly slower. This dissociation of CNV rebound and reaction time could provide an objective neurophysiological tool to probe attention functions in both normal and clinical populations.

Adolescent↗
PubMed2001

Event-related potentials, CNV, readiness potential, and movement accompanying potential recorded from posterior thalamus in human subjects. A SEEG study.

Intracranial recordings were obtained from three patients with intractable chronic pain who underwent analgesic electrical stimulation of the contralateral thalamus. Multilead electrode made it possible to record from several thalamic nuclei. The electrode was targeted into the ventroposterolateral (VPL) nucleus of the thalamus. During separate recording sessions, the following tests were performed: somatosensory evoked potentials (SEP) of the median or posterior tibial nerve, event-related cognitive potentials (auditory oddball P3 wave), readiness potential (RP) and contingent negative variation (CNV) using auditory warning (S1) and visual imperative (S2) stimuli. The movement accompanying potential (MAP), which was present in the VPL in all but one of the recordings, behaved as a far-field potential. Recordings obtained from the VPL confirmed its established role as a relay nucleus, processing somatosensory information to the primary somatosensory cortex. The VPL generated the 'thalamic' SEP, which was the only potential regularly recorded in this nucleus. In the recordings from one patient (No. 3), auditory and visual evoked potentials of the CNV protocol, peaking at approximately 300 ms, were obtained from the VPL and appeared to be generated in situ. Neither RP, CNV nor 'oddball' ERPs appeared in the VPL. From the pulvinar, only a visually evoked potential was recorded. Oddball P3, RP, CNV, and middle and long latency auditory and visual potentials (evoked in the CNV paradigm) appeared to be generated 'dorsally' to the VPL, probably in the nucleus posterolateralis (PL). This structure may therefore be involved in both the processing of afferent information and in cognitive operations.

Aged↗
PubMed1991

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.

Aged↗
PubMed2001

Radiotherapy for age-related macular degeneration: is there a benefit for classic CNV?

AIM: To evaluate the efficacy of radiotherapy in the treatment of subfoveal classic and occult choroidal neovascularization (CNV) in age-related macular degeneration (AMD) under strict fixation control. METHODS: Twenty-seven eyes of 27 patients with subfoveal CNV as a result of AMD were treated with a total dose of 20 Gy in 10 fractions (10 well-defined, 17 occult). Fixation monitoring was achieved by installing a TV camera with an attached fixation light 3 cm from the cornea of the eye being treated. Visual acuity and fluorescein angiography were obtained before and 6 months after treatment. Fifteen eyes of 15 patients served as controls (4 well-defined, 11 occult). RESULTS: After 6 months the treated group showed an average decrease in visual acuity of 27%; the control group experienced a decrease of 31%. Membrane size increased by 56% in the treated group and by 28% in the control group. There was no statistically significant difference. Within the subgroup analysis, however, patients with classic CNV suffered significantly less visual loss than in the control group. CONCLUSION: Radiation therapy under optimized treatment conditions by fixation monitoring failed to control further growth in membrane size in both classic and occult CNV. Regarding visual acuity, however, patients with classic CNV seem to benefit from radiation treatment compared to the natural course.

Adolescent↗
PubMed1989

CNV abnormalities following closed head injury.

Event-related potentials (ERPs) were recorded in a GO/NO-GO reaction time task from 20 closed head injury patients, at least 6 months postinjury, and from 20 controls. In this task the pitch of an initial tone (Sl) indicated whether or not a response was required to a second tone (S2) occurring 1.5 s later. In the control group both the early, frontal-maximum, and the later vertex-maximum, components of the contingent negative variation (CNV) were larger on GO than NO-GO trials. In the patients, the early frontal CNV wave did not differentiate GO and NO-GO trials, and the late CNV showed a smaller separation between these trial types than did the late CNV of the control group. These CNV abnormalities may reflect impairments in selectively orienting to salient stimuli, and in differential response preparation. Such impairments might in turn reflect the damage to the frontal lobes and/or their connections that commonly occurs as a result of closed head injury.

Acoustic Stimulation↗
PubMed1976

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 politive 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.

Adult↗
PubMed1978

Motivational slow negative potential shift (CNV) related to thalamotomy.

The alteration of cortical electrical activity induced by imperative stimulation following warning stimulation, contigent negative variation (CNV), and psychological changes following thalamotomy for relief of intractable pain (CM) and tremor (VL) are studied, since CNV has a close relationship with the degree of psychological activity. Ventrolateral thalamotomy does not have any effect on the amplitude of cortical CNV, but the ventromedioposterior part of the centre median has a generating action of CNV in itself and it has facilitatory effects upon cortical CNV. According to these results, the effective mechanism of centre median thalamotomy for relief of intractable pain is caused by suppression of attention and expectancy for exogenous stimuli following lesions of the centre median.

Contingent Negative Variation↗
PubMed2006

Large scale copy number variation (CNV) at 14q12 is associated with the presence of genomic abnormalities in neoplasia.

BACKGROUND: Advances made in the area of microarray comparative genomic hybridization (aCGH) have enabled the interrogation of the entire genome at a previously unattainable resolution. This has lead to the discovery of a novel class of alternative entities called large-scale copy number variations (CNVs). These CNVs are often found in regions of closely linked sequence homology called duplicons that are thought to facilitate genomic rearrangements in some classes of neoplasia. Recently, it was proposed that duplicons located near the recurrent translocation break points on chromosomes 9 and 22 in chronic myeloid leukemia (CML) may facilitate this tumor-specific translocation. Furthermore, approximately 15-20% of CML patients also carry a microdeletion on the derivative 9 chromosome (der(9)) and these patients have a poor prognosis. It has been hypothesised that der(9) deletion patients have increased levels of chromosomal instability. RESULTS: In this study aCGH was performed and identified a CNV (RP11-125A5, hereafter called CNV14q12) that was present as a genomic gain or loss in 10% of control DNA samples derived from cytogenetically normal individuals. CNV14q12 was the same clone identified by Iafrate et al. as a CNV. Real-time polymerase chain reaction (Q-PCR) was used to determine the relative frequency of this CNV in DNA from a series of 16 CML patients (both with and without a der(9) deletion) together with DNA derived from 36 paediatric solid tumors in comparison to the incidence of CNV in control DNA. CNV14q12 was present in approximately 50% of both tumor and CML DNA, but was found in 72% of CML bearing a der(9) microdeletion. Chi square analysis found a statistically significant difference (p <or= 0.001) between the incidence of this CNV in cancer and normal DNA and a slightly increased incidence in CML with deletions in comparison to those CML without a detectable deletion. CONCLUSION: The increased incidence of CNV14q12 in tumor samples suggests that either acquired or inherited genomic variation of this new class of variation may be associated with onset or progression of neoplasia.

Child↗
PubMed2004

[Preclinical and clinical profile of verteporfin, a potent photodynamic therapy drug for CNV secondary to AMD].

Age-related macular degeneration (AMD) is the leading cause of blindness among people aged over 50 years in the western world. Verteporfin (Visudyne) is the first light-activated drug indicated for the treatment of patients with AMD caused by subfoveal choroidal neovascularization (CNV). This form of AMD is characterized by the development of abnormal blood vessels on the back of the retina that leak and cause scarring, resulting in central vision loss. Following intravenous administration, verteporfin selectively accumulates within proliferating tissue, including neovasculature, probably via low density lipoprotein receptors. The verteporfin is then activated by shining a specific wavelength of light with a nonthermal laser on the affected area in the eye. This process, called photodynamic therapy (PDT), generates reactive free radicals and highly reactive singlet oxygen in the target cells in the eye, causing damage and occlusion of the CNV and resulting in closure of the abnormal vessels and cessation of leakage. In experimentally induced CNV in animal models and in randomized, controlled clinical trials of patients with CNV due to AMD, verteporfin PDT has been shown to selectively occlude abnormal vessels without significantly altering overlying photoreceptors. Verteporfin therapy for CNV in Japanese patients had a similar or better angiographic and vision effect as that observed in Caucasian patients, with the same safety profile.

Animals↗
PubMedDate not supplied

Bilateral CNV associated with optic nerve drusen treated with photodynamic therapy with verteporfin.

PURPOSE: To report a case of bilateral choroidal neovascularization (CNV) associated with optic nerve drusen (OND) treated with photodynamic therapy (PDT) with verteporfin. METHODS: A 10-year-old girl with juxtapapillary CNV in the right eye and juxtapapillary and juxtafoveal CNV in the left eye associated with OND underwent PDT with verteporfin in both eyes. RESULTS: Visual acuity increased from 20/160 to 20/25 in the right eye and from 20/1000 to 20/25 in the left eye after two sessions of PDT and 2 years of follow-up. CNV showed no leakage after two PDT sessions in both eyes and no recurrence was observed. CONCLUSIONS: Subfoveal CNV is an uncommon complication of OND and excellent anatomic and functional results can be obtained with PDT.

Child↗
PubMed1987

Two-level CNV and extrication wave in human brain.

In this experiment, the paradigm of CNV is changed, with two warning stimuli presented and the key press for discrimination exchanged in order to reject the motor factor in CNV. The main results are: Second level of CNV is increased, an extrication wave is discovered. Various hypotheses about CNV are discussed, proposing that the psychological factor in CNV is not a unitary one, but the increase of the mental load which is synthetically composed of many psychological factors.

Adult↗
PubMed2003

When time is up: CNV time course differentiates the roles of the hemispheres in the discrimination of short tone durations.

Numerous studies have suggested that the CNV (contingent negative variation), a negative slow wave developing between a warning and an imperative stimulus, reflects, among other things, temporal processing of the interval between these two stimuli. One aim of the present work was to specify the relationship between CNV activity and the perceived duration. A second aim was to establish if this relationship is the same over the left and right hemispheres. Event-related potentials (ERPs) were recorded for 12 subjects performing a matching-to-sample task in which they had to determine if the duration of a tone (490 ms, 595 ms, 700 ms, 805 ms, and 910 ms) matched that of a previously presented standard (700 ms). CNV activity measured at the FCZ electrode was shown to increase until the standard duration had elapsed. By contrast, right frontal activity increased until the end of the current test duration, even when the standard duration had elapsed. Moreover, for long test durations (805 ms and 910 ms), correlations were observed between CNV peak latency and subjective standard, over left and medial frontal sites. We propose that left and medial frontal activity reflects an accumulation of temporal information that stops once the memorized standard duration is over, while right frontal activity subserves anticipatory attention near the end of the stimulus.

Adolescent↗