Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In healthy subjects and patients with chronic alcoholism, the ability to construct in mind geometric figures in conditions of masking was studied by means of recording the number of correct decisions, the reaction time and evoked cortical electrical activity. It has been found that solution of visual-spatial task of mentally constructing geometric figures is accomplished better if a figure-standard can be formed from the presented fragments. During solution of the visual-spatial task in norm the reaction time is shorter if the information comes "directly" to the right hemisphere. Such interhemispheric differences are not observed at chronic alcoholic intoxication. In patients with chronic alcoholism the late components of EPs N200 and P300 developed with a longer latency and lesser amplitude than in healthy subjects. The greatest depression of cortical activity is observed in the right hemisphere.
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PMID:[Lateralization of visuo-spatial function during masking in healthy subjects and in patients with chronic alcoholism]. 280 Jun 90

P300 is known as a wave which enables the evaluation of cognitive function in neuropsychology and psychiatry. The most reliable result in psychoses was an amplitude reduction. Since similar wave alteration occurred not only in psychoses but also in dementia, the P300 reduction was too unspecific to serve as criteria for differential diagnosis. By means of topographical procedures it could be found out that the well defined P300 fields underwent characteristic changes in psychoses which even allowed a differentiation between different subgroups in schizophrenia. In hebephrenics the frontal field was very low whereas the paranoid group showed a lateralized P300-pattern with lower amplitudes in the right parieto-temporal area. In depression the P300-pattern was identical to the fields known in geriatric controls. The results will be discussed regarding other structural and functional imaging procedures. By means of topographical display of P300 the specificity of cognitive waves can be augmented considerably with the possibility to differentiate between different types of psychoses.
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PMID:[Topography of P300 in psychiatry--1. Cognitive P300 fields in psychoses]. 313 Nov 5

P300 and Dexamethasone Suppression Test (DST) have been carried out on 60 depressed patients classified according to the DSM-III and compared to controls. DST discriminated with a high specificity (85%) and sensitivity (80%) melancholics from controls and from other groups of depressed patients: post-dexamethasone cortisol levels were significantly higher in the former. The amplitude of P300 was significantly smaller in depressives as compared to controls. This was more pronounced in the melancholic group but was not specific to them. On the other hand, correlation analyses showed that the weaker the P300 amplitude, the higher the score at the Hamilton Rating Scale for Depression [Acta psychiat. belg., 87, 694-703 (1987)].
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PMID:[Dexamethasone suppression test and endogenous components of evoked potentials in depressed subjects]. 345 88

The authors measured electrical reactive potentials in the posterior associative and frontal areas, originating in response to winning or losing of the serve in tennis game shown on the video which served as a model of positive and negative emotional reactions. The studied potentials consisted of four waves: P300, N600, P800 and N1000. Healthy subjects experiencing positive emotions showed a more marked negative nature of the potentials in the left posterior associative zone while negative emotions were associated with the presence of predominantly negative potentials in the right frontal area. Patients with protracted depression presented a negative shift of potentials in both right posterior associative zone and left frontal area. The results obtained indicate that protracted depression is attended by impaired topography of the cortical processes associated with positive and negative emotions.
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PMID:[Electric reactive potentials to events with a positive and negative coloring in patients with protracted depression]. 359 Nov 42

The P300 component was elicited by an auditory oddball paradigm in 55 normal adults from a wide age range: 19 patients with dementia, 17 patients with depression, and 15 patients with schizophrenia. Normal P300 latency at a given age was predicted by using an age regression equation that had been calculated on the basis of the entire normal sample. Using this procedure, an abnormal delay in latency (greater than 2 SD) was found in approximately 80% of the dementia patients. However, when normal latency was predicted with a slightly greater degree of reliability according to separate equations for adults younger and older than 63 years, an abnormal delay in P300 was found to be less sensitive and specific to dementia. Suggestions for enhancing the diagnostic utility of the P300 component are proposed.
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PMID:The differential diagnosis of dementia using P300 latency. 375 62

The present study constitutes an approach to the action mechanisms of nitrous oxide (N2O) by assessing both the subjective effects induced by the inhalation of this anaesthetic gas, and their electrophysiological correlates, i.e., spontaneous EEG, analyzed by a Fourier algorithm, AEP and CNV. The experiment was conducted single blind in 9 volunteers under 3 recording conditions: inhalation of air, of a mixture of 25% N2O--75% O2, and of a mixture of 50% N2O--50% O2. A latin-square design was used. Polymorphic effects of N2O were evidenced on behaviour and on CNS: some of the behavioural manifestations could evoke a depression of SNC: muscle relaxation with difficulty of motor initiation, psychomotor slowing, slower EEG with diminution of the percent alpha component and increase in the percent theta and delta, loss of amplitude of both exogenous (N1) and endogenous (P300) components of the AEP. Conversely, other manifestations were observed that are compatible with an activation of the CNS: increase of sensory perceptions, appearance of perceptual illusions, maintenance of a high CNV amplitude and lengthening of its duration. This dual effect of N2O suggests a dissociative action at the different levels of the CNS.
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PMID:[Quantified EEG and CNV changes during inhalation of nitrous oxide]. 715 49

Event-related potentials (ERPs) were recorded from 25 elderly patients and 26 normal controls to determine whether ERPs can aid in the differential diagnosis of depression and dementia. Two ERP measures were used: (1) P300 latency, and (2) N1 amplitude increase for a 14db tone intensity increase (i.e. intensity augmenting-reducing). While augmenting-reducing proved of little benefit, P300 latency was highly correlated with Mini-Mental State (MMS) scores and correctly identified 10 of 18 demented patients. None of the seven patients with psychiatric disorders (primarily depression) or 26 normals were misclassified. Better differentiation of depression and dementia resulted from combined use of P300 latency and MMS scores.
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PMID:Event-related potentials in psychiatry: differentiating depression and dementia in the elderly. 718 69

Long latency event-related auditory evoked potentials, particularly the P300 wave, constitute an objective electrophysiological index of cognitive function. For this reason, these potentials have been studied in a series of 101 patients with multiple sclerosis (MS), classified according to McAlpine's criteria into definite, probable and possible cases. The patients were also classified as depressed or non-depressed according to the DSM-III and Research Diagnostic Criteria. They were also subjected to a battery of psychometric tests. In the patient population the N200 and P300 latencies were increased, as were the P200 latencies, when compared with a control population. This electrophysiological pattern had previously been observed in other conditions characterised by subcortical lesions. Partial correlations (at constant disease duration) between the disability score and the cognitive deficit were found to be significant. Patients with an increased P300 latency had a greater disability and the P300 latency was significantly correlated with the duration of the illness. The N200 and P300 latencies were increased in depressed MS subjects, but this increase did not reach the level of significance. Depression was more frequent in the more severely handicapped patients. This suggests that the origin of the depression seen in multiple sclerosis is only partly organic, and that it is one of the factors contributing to the subcortical cognitive deficit in multiple sclerosis. Progressive forms of the disease exhibited the most profound cognitive deficit, and the most marked increase in P300 latency.
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PMID:Event-related auditory evoked potentials and multiple sclerosis. 768 67

"Oddball" paradigm studies of auditory P300 have yielded conflicting results in migraine. We therefore undertook an additional study of auditory event-related potentials (ERPs) using an improved method of EEG processing, strict criteria for patients selection, and comparison with behavioral data. Twenty-one healthy subjects were compared to 20 patients suffering from migraine without aura between attacks. Migraine patients differed significantly from control subjects on several parameters: shorter latency of N1 (Cz) evoked by standard stimuli, longer latencies of both P3a and P3b (Pz) evoked by target stimuli, longer interval between N1 and P3b (Cz), smaller P3b (Cz) amplitude, longer reaction time (RT), higher number of errors (false alarm and/or omissions) and higher mean score on Plutchik-Van Praag's (PVP) inventory for depression. Errors were significantly correlated with RT and PVP scores. From a behavioral perspective, these results may suggest that patients suffering from migraine without aura between attacks display a higher level of arousal and more superficial attention, but require more time for automatic and/or voluntary processes. According to the inverted U-shaped relationship between performance and arousal, these patients may have difficulties in adjusting their attention level to perform a task in a optimal way.
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PMID:Cognitive functions in migraine without aura between attacks: a psychophysiological approach using the "oddball" paradigm. 774 25

The relationship between delusions and hallucinations (psychotic features) in melancholic depression and auditory P300 was studied. Forty patients with melancholic depression as per DSM-III-R were studied, 20 of whom had hallucinations and/or delusions. The 20 patients of the two groups were individually matched on age, gender, sociodemographic variables, and psychopathology (except for psychotic features). Auditory P300 obtained by the "oddball paradigm" showed that those with hallucinations and/or delusions had a significantly smaller P3 amplitude. Significant correlations between "psychotic features" and P3 amplitude was found. Implications of these findings on research, classification, and management of depression have been outlined.
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PMID:A study of P300 in melancholic depression--correlation with psychotic features. 801 98


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