Karina Karolina Kedzior

Prepulse inhibition (PPI) of auditory startle reflex is associated with PPI of auditory-evoked theta oscillations in healthy humans

The aim of the current study was to investigate the auditory-evoked theta oscillatory activity associated with prepulse inhibition (PPI) of the startle reflex in healthy humans. Concurrent electroencephalogram (EEG) and auditory startle reflex were recorded from 19 healthy controls during Pulse-Alone and Prepulse + Pulse trials with 60, 120, and 240 ms prepulse-pulse intervals. Compared to Pulse-Alone trials significant PPI of the startle reflex occurred on all Prepulse + Pulse trials and a significant startle latency reduction occurred on 60 and 120 ms Prepulse + Pulse trials. The largest evoked potentials to auditory stimuli occurred at fronto-central locations. PPI of theta oscillations occurred at frontal, central, and parietal locations. These results suggest that PPI functions not only as sensory-motor gating but also as sensory-cognitive gating since theta oscillations are involved in control of cognitive processes. Absence of significant correlations between PPI of the startle reflex and of theta oscillations at all electrode locations indicates that the two processes may be controlled by different neural mechanisms.

Cognitive functioning and deep transcranial magnetic stimulation (DTMS) in major psychiatric disorders: A systematic review.

Deep transcranial magnetic stimulation (DTMS) is a non-invasive brain stimulation method mostly utilised in the treatment of major depression. The aim of the current study was to systematically review the literature on the cognitive effects of DTMS applied with the H-coil system in major psychiatric disorders. Following a literature search in PsycInfo and PubMed (any time to December 2015), 13 out of 32 studies on DTMS and cognitive functioning were included in the current review. Three studies included 38 healthy participants, eight studies included 158 unipolar or bipolar depression patients and two studies included 45 schizophrenia patients. Low-frequency DTMS (1-3 sessions) had little effect on cognitive functioning in healthy participants. The most consistent cognitive and clinical improvements were reported in the short-term (after 20 daily sessions of high-frequency DTMS with H1-coil) in studies with major depression patients. There was also a trend towards a short-term cognitive and clinical improvement in studies with schizophrenia patients. High-frequency DTMS might improve cognitive functioning and alleviate clinical symptoms in the short-term, particularly in major depression. However, this conclusion is based on data from mostly uncontrolled, open-label studies with patients receiving concurrent antidepressants or antipsychotics. Randomised, sham-controlled trials are needed to investigate the magnitude of the cognitive outcomes of DTMS in the short-term and beyond the daily stimulation phase in major psychiatric disorders.

Auditory-evoked EEG oscillations associated with prepulse inhibition (PPI) of auditory startle reflex in healthy humans

The aim of the current study was to investigate the prepulse inhibition (PPI) of auditory-evoked delta, alpha, and gamma oscillations. Concurrent EEG and auditory startle reflex were recorded from 15 healthy participants during Pulse-Alone and Prepulse+Pulse trials with 60, 120, and 240 ms prepulse-pulse intervals. A significant PPI of the startle reflex on all Prepulse+Pulse trials was associated with a significant PPI of alpha oscillations at central and temporal locations and of gamma oscillations at frontal, central, and temporal locations on some Prepulse+Pulse trials. PPI of delta oscillations was not observed. These results confirm our recent finding stating that PPI functions as a sensory-motor as well as a sensory-cognitive gating mechanism because alpha and gamma oscillations mediate cognitive processes.

Acute reduction in anxiety after deep transcranial magnetic stimulation (DTMS) in unipolar major depression- a systematic review and meta-analysis

The current study investigated the anxiolytic properties of the deep transcranial magnetic stimulation (DTMS) in unipolar major depression using a systematic literature review and meta-analysis. Compared to baseline, large anxiolytic and antidepressant outcomes were obtained after 20 daily sessions of high-frequency DTMS according to data from six open-label studies with 95 patients. Unlike the antidepressant effect, the anxiolytic effect was more heterogeneous among studies and did not depend on concurrent treatment with antidepressants.

EVENT-RELATED POTENTIALS DURING AUDITORY ODDBALL, AND COMBINED AUDITORY ODDBALL–VISUAL PARADIGMS

The purpose of the current study was to investigate the properties of a new modification of the classical auditory oddball paradigm (auditory oddball paradigm combined with passive visual stimulation, AERPs+VEPs) and compare the scalp topography obtained with the new paradigm and the classical auditory oddball paradigm (AERPs) in healthy humans. The responses to bimodal stimulation, and to the classical oddball paradigm were similar to those reported in other studies in terms of location, amplitudes, and latencies of P1, N1, P2, N2, and P300. The new modification of the oddball paradigm produced P300 at fronto-central locations in contrast to centro-parietal locations during the classical oddball paradigm. The amplitudes and latencies of P300 were also significantly larger during the new than the classical paradigm. Furthermore, the amplitudes of N1 and P2, but not N2 were significantly higher and differed in location during the new paradigm in response to both target and standard stimuli. The latencies of all three waves were significantly longer and the latency of P2 differed in location between the new and the classical paradigms in response to only the standard stimuli. The results of this study suggest that the new modification of the classical oddball paradigm produces different neural responses to the classical oddball paradigm. Therefore, this modification can be used to investigate dysfunctions in sensory and cognitive processing in clinical samples.

Event-related potentials to visual, auditory, and bimodal (combined auditory-visual) stimuli.

The purpose of this study was to investigate the response properties of event related potentials to unimodal and bimodal stimulations. The amplitudes of N1 and P2 were larger during bimodal evoked potentials (BEPs) than auditory evoked potentials (AEPs) in the anterior sites and the amplitudes of P1 were larger during BEPs than VEPs especially at the parieto-occipital locations. Responses to bimodal stimulation had longer latencies than responses to unimodal stimulation. The N1 and P2 components were larger in amplitude and longer in latency during the bimodal paradigm and predominantly occurred at the anterior sites. Therefore, the current bimodal paradigm can be used to investigate the involvement and location of specific neural generators that contribute to higher processing of sensory information. Moreover, this paradigm may be a useful tool to investigate the level of sensory dysfunctions in clinical samples.

Clinically-relevant outcomes of deep transcranial magnetic stimulation (dtms) in unipolar major depression: a systematic review and meta-analysis

using a systematic review and meta-analysis. Methods: A systematic literature search of PsycInfo and Medline (in EBSCO; any date till 24.06.2016) identified k1⁄422 open-label studies with ‘DTMS’ and ‘depression’ in titles. After exclusion of studies with fewer than 5 patients (k1⁄44), data from the same patients (k1⁄44), reviews (k1⁄43), diagnoses of bipolar or alcohol use disorders (k1⁄42), and other scales than Hamilton Depression Rating Scale (HDRS; k1⁄41), k1⁄48 studies were included in this analysis. Predictors of clinical outcomes (standardised change scores on HDRS and Hamilton Anxiety Rating Scale, HARS, response, remission, and dropout rates) were evaluated using univariate, randomeffects meta-regressions with inverse-variance weights. Results: Eight studies included 128 patients with treatment-resistant unipolar depression (average onset age of 17-45 years, illness duration of 3-30 years, age of 41-54 years, 14-67% females/study). High-frequency DTMS (18-20 Hz) with H1-coil was administered over 20 sessions as either add-on or monotherapy (in k1⁄42 studies with 26 patients). The antidepressant outcomes of DTMS did not depend on the demographics (mean age or % females/study) or the clinical patient characteristics (mean onset age or illness duration). Relative to monotherapy, DTMS as an add-on therapy tended to produce greater reduction in the HDRS scores (p1⁄4.08). The reduction in the HARS scores (in k1⁄46 studies) was significantly associated with higher mean age of patients/study (p1⁄4.04). Discussion: DTMS may improve the antidepressant outcomes as an addon therapy. It may also enhance the anxiolytic outcomes in older patients with major depression. Additional data are necessary to examine predictors of clinical response to DTMS in unipolar major depression using multivariate statistical methods.

Challenges in comparing the acute cognitive outcomes of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) vs. electroconvulsive therapy (ECT) in major depression: A systematic review

The present study aimed to systematically compare the cognitive outcomes of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) and electroconvulsive therapy (ECT) in head-to-head studies with major depression (MDD) patients. A systematic literature search identified six studies with 219 MDD patients that were too heterogeneous to reliably detect meaningful differences in acute cognitive outcomes after ECT vs. HF-rTMS. Cognitive effects of brain stimulation vary depending on the timeframe and methods of assessment, stimulation parameters, and maintenance treatment. Thus, acute and longer-term differences in cognitive outcomes both need to be investigated at precisely defined timeframes and with similar instruments assessing comparable functions.

An Update of a Meta-Analysis on the Clinical Outcomes of Deep Transcranial Magnetic Stimulation (DTMS) in Major Depressive Disorder (MDD)

Deep transcranial magnetic stimulation (DTMS) is a noninvasive therapy for treatment-resistant major depressive disorder (MDD). The current study aimed to update a previous meta-analysis by investigating the acute and longer-term clinical outcomes of DTMS and their possible predictors (patient characteristics and stimulation parameters) in unipolar MDD. A systematic literature search identified 11 studies with 282 treatment-resistant, unipolar MDD patients. The clinical outcomes (depression severity, response and remission rates) were evaluated using random-effects meta-analyses. High frequency and intensity DTMS protocol with H1-coil had significant acute antidepressant outcomes and improved some cognitive functions after 20 daily sessions in unipolar MDD. Response rates tended to increase with lower severity of illness. Antidepressant effects were prolonged if maintenance DTMS was used after daily stimulation phases. DTMS consistently improves various symptom domains (antidepressant, cognitive) in treatment-resistant unipolar MDD.

Definition of intercultural competence (IC) in undergraduate students at a private university in the USA: A mixed-methods study

Introduction Intercultural competence (IC) is an important skill to be gained from higher education. However, it remains unclear what IC means to students and what factors might influence their definitions of IC. The aim of the current study was to qualitatively assess how students at one higher education institution in the USA define IC and to quantitatively test for relationships among IC components and various demographic characteristics, including intercultural experience and study context. A further aim was to descriptively compare the IC definitions from the US sample with the definitions obtained from another sample of university students in Germany. Materials and methods A purposive sample of n = 93 undergraduate, second semester students at Dickinson College, USA, participated in the study by completing an online questionnaire. The qualitative data were content-analyzed to define the dimensions of IC. The quantitative data were cluster-analyzed to assess the multivariate relationships among the IC components and the demographic characteristics of the sample. Results The most important dimensions of IC were Knowledge, External Outcomes (interaction, communication), and Attitudes (respect, tolerance) according to the US sample. The most frequently chosen dimensions of IC differed between both samples: Knowledge was chosen by the sample in the USA while External Outcomes was chosen by the sample in Germany. Relative to the US sample, significantly more students chose Attitudes, External Outcomes, and Intrapersonal Skills in the sample in Germany. The relationships among IC components and demographic characteristics were only weak in the US sample. A person with IC was rated as Open-minded and Respectful by students who lived predominantly in the USA or Tolerant and Curious by those who lived outside the USA for at least six months. Discussion The current results suggest that students residing in two countries (USA or Germany) define IC using similar dimensions. However, IC definitions may depend on the intercultural experience and the current global discourse. Longitudinal studies with representative samples are required to assess how IC definitions change over time.