The impact of ziprasidone in combination with sertraline on visually-evoked event-related potentials in depressed patients with psychotic features

In adult psychiatry early recognition and treatment of schizophrenia has become a major goal because of manifold evidence of a relation between delayed initiation of treatment and an unfavourable developmental course. The duration of untreated psychosis (DUP) seems to be significantly prolonged in adolescents compared to adults due to both a protracted sub-threshold development of psychotic features and the failure of families and health professionals to take seriously the initial signs of psychosis that mimic quasi normal adolescent emotional perturbations. Although in adults studies have shown a subset of prodromal signs and attenuated psychotic features to have predictive evidence for the development of schizophrenia, these symptoms however seem of limited specificity in adolescence. Basic symptoms represent subjective experiences of the prodromal phase and will be presented in a sample of schizophrenic adolescents in comparison to non-psychotic patients and normal controls. Results reveal that basic symptoms do not show any specificity for schizophrenia, but schizophrenics present with higher amounts of basic symptoms in the prodromal phase compared to non-psychotic controls. For early recognition a combination of psychopathological and biological markers seems fruitful. First data on perceptual closure and event related potentials of the optic system will be presented that seem to differentiate between early and late onset schizophrenia.

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ASSESSING THE IMPACT OF CONGRUENT AND INCONGRUENT STIMULUS IN STROOP TASK, USING EVENT-RELATED POTENTIALS (ERP) IN PATIENTS WITH DEPRESSION

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237218500345 ◽

2018 ◽

Vol 30 (05) ◽

pp. 1850034

Author(s):

Yeganeh Shahsavar ◽

Majid Ghoshuni

Keyword(s):

Stroop Task ◽

Time Window ◽

Event Related Potentials ◽

Peak Time ◽

Eeg Signals ◽

Incongruent Stimulus ◽

Related Potentials ◽

Recording Channel ◽

The Mean ◽

The Impact

The main goal of this event-related potentials (ERPs) study was to assess the effects of stimulations in Stroop task in brain activities of patients with different degrees of depression. Eighteen patients (10 males, with the mean age [Formula: see text]) were asked to fill out Beck’s depression questionnaire. Electroencephalographic (EEG) signals of subjects were recorded in three channels (Pz, Cz, and Fz) during Stroop test. This test entailed 360 stimulations, which included 120 congruent, 120 incongruent, and 120 neutral stimulations. To analyze the data, 18 time features in each type of stimulus were extracted from the ERP components and the optimal features were selected. The correlation between the subjects’ scores in Beck’s depression questionnaires and the extracted time features in each recording channel was calculated in order to select the best features. Total area, and peak-to-peak time window in the Cz channel in both the congruent and incongruent stimulus showed significant correlation with Beck scores, with [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text], respectively. Consequently, given the correlation between time features and the subjects’ Beck scores with different degrees of depression, it can be interpreted that in case of growth in degrees of depression, stimulations involving congruent images would produce more challenging interferences for the patients compared to incongruent stimulations which can be more effective in diagnosing the level of disorder.

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Expect the unexpected: Processing of sensory information in the anticipation of predictable and unpredictable threats

Research in Social Change ◽

10.2478/rsc-2019-0005 ◽

2019 ◽

Vol 11 (1) ◽

pp. 80-115

Author(s):

Eva Koderman

Keyword(s):

Sensory Information ◽

Event Related Potentials ◽

Perceived Threat ◽

Subject Design ◽

Unpleasant Picture ◽

Before And After ◽

Attentional Engagement ◽

Related Potentials ◽

The Impact ◽

Threat Of Shock

Abstract Anxiety is characterized by a sustained state of heightened vigilance due to uncertain danger, producing increased attention to a perceived threat in one's environment. To further examine this exploited the temporal resolution afforded by event-related potentials to investigate the impact of predictability of threat on early perceptual activity. We recruited 28 participants and utilized a within-subject design to examine hypervigilance in anticipation of shock, unpleasant picture and unpleasant sound during a task with unpredictable, predictable and no threat. We investigated if habituation to stimuli was present by asking the participants to rate unpleasantness and intensity of the stimuli before and after the experiment. We observed hypervigilance in the unpredictable threat of shock. Habituation was observed for the visual stimuli. The present study suggests that unpredictability enhances attentional engagement with neutral somatosensory stimuli when the threat is of the same modality, meaning we observed the presence of hypervigilance which is a characteristic of anxiety.

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Error-Monitoring is Modulated by School Pedagogy

10.31219/osf.io/7nbqz ◽

2019 ◽

Author(s):

Solange Denervaud ◽

Jean-François Knebel ◽

Emeline Mullier ◽

Patric Hagmann ◽

Micah M. Murray

Keyword(s):

Fluid Intelligence ◽

Recognition Task ◽

Event Related Potentials ◽

Anterior Cingulate ◽

Error Monitoring ◽

Traditional Curriculum ◽

Source Estimation ◽

Related Potentials ◽

School Pedagogy ◽

The Impact

Within an inherently dynamic environment, unexpected outcomes are part of daily life. Performance monitoring allows us to detect these events and adjust behavior accordingly. The necessity of such an optimal functioning has made error-monitoring a prominent topic of research over the last decades. Event-related potentials (ERPs) have differentiated between two brain components involved in error-monitoring: the error-related negativity (ERN) and error-related positivity (Pe) that are thought to reflect detection vs. emotional/motivational processing of errors, respectively. Both ERN and Pe depend on the protracted maturation of the frontal cortices and anterior cingulate through adolescence. To our knowledge, the impact of schooling pedagogy on error-monitoring and its brain mechanisms remains unknown and was the focus of the present study. Swiss schoolchildren completed a continuous recognition task while 64-channel EEG was recorded and later analyzed within an electrical neuroimaging framework. They were enrolled either in a Montessori curriculum (N=13), consisting of self-directed learning through trial-and-error activities with sensory materials, or a traditional curriculum (N=14), focused on externally driven activities mainly based on reward feedback. The two groups were controlled for age, gender, socio-economic status, parental educational style, and scores of fluid intelligence. The ERN was significantly enhanced in Montessori schoolchildren (driven by a larger response to errors), with source estimation differences localized to the cuneus and precuneus. In contrast, the Pe was enhanced in traditional schoolchildren (driven by a larger response to correct trials), with source estimation differences localized to the ventral anterior cingulate. Receiver operating characteristic (ROC) analysis demonstrated that the ERN and Pe could reliably classify if a child was following a Montessori or traditional curriculum. Brain activity subserving error-monitoring is modulated differently according to school pedagogy.

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Neural Biases to Covert and Overt Signals of Fear: Dissociation by Trait Anxiety and Depression

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2007.19.10.1595 ◽

2007 ◽

Vol 19 (10) ◽

pp. 1595-1608 ◽

Cited By ~ 45

Author(s):

Leanne M. Williams ◽

Andrew H. Kemp ◽

Kim Felmingham ◽

Belinda J. Liddell ◽

Donna M. Palmer ◽

...

Keyword(s):

Trait Anxiety ◽

Time Course ◽

Event Related Potentials ◽

Anxiety And Depression ◽

Controlled Processing ◽

Parallel Networks ◽

Related Potentials ◽

Conscious Attention ◽

The Impact ◽

Emotion Encoding

Although biases toward signals of fear may be an evolutionary adaptation necessary for survival, heightened biases may be maladaptive and associated with anxiety or depression. In this study, event-related potentials (ERPs) were used to examine the time course of neural responses to facial fear stimuli (versus neutral) presented overtly (for 500 msec with conscious attention) and covertly (for 10 msec with immediate masking to preclude conscious awareness) in 257 nonclinical subjects. We also examined the impact of trait anxiety and depression, assessed using psychometric ratings, on the time course of ERPs. In the total subject group, controlled biases to overtly processed fear were reflected in an enhancement of ERPs associated with structural encoding (120–220 msec) and sustained evaluation persisting from 250 msec and beyond, following a temporo-occipital to frontal topography. By contrast, covert fear processing elicited automatic biases, reflected in an enhancement of ERPs prior to structural encoding (80–180 msec) and again in the period associated with automatic orienting and emotion encoding (230–330 msec), which followed the reverse frontal to temporo-occipital topography. Higher levels of trait anxiety (in the clinical range) were distinguished by a heightened bias to covert fear (speeding of early ERPs), compared to higher depression which was associated with an opposing bias to overt fear (slowing of later ERPs). Anxiety also heightened early responses to covert fear, and depression to overt fear, with subsequent deficits in emotion encoding in each case. These findings are consistent with neural biases to signals of fear which operate automatically and during controlled processing, feasibly supported by parallel networks. Heightened automatic biases in anxiety may contribute to a cycle of hypervigilance and anxious thoughts, whereas depression may represent a “burnt out” emotional state in which evaluation of fear stimuli is prolonged only when conscious attention is allocated.

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