Age-related declines in motion perception have been well documented. We investigated the impact of age on electrophysiological correlates of motion perception, namely the P1 and N2 components of motion onset visual evoked potentials (MO-VEPs). Additionally, we used a model of response times based on the diffusion model to pinpoint the cognitive processes affected by aging. Twelve healthy adults (age (55years) and 19 elderly (age )55years) performed a motion direction discrimination task during EEG recording. Behaviorally, younger and older participants had similar, high accuracy rates - 98% correct, but older adults exhibited 85ms longer response times. Fitting behavioral results with a diffusion model revealed differences between young adults and elderly in non-decision time, which we argue reflects an early perceptual stage. Electrophysiologically, aging effects were present at MO-VEPs P1 and N2 components at the posterior sites. For the P1 component, older as compared to younger adults showed greater topographical voltage distribution. For the N2 component of elderly as compared to young adults we found delayed onsets and diminished amplitudes. We did not find any significant correlations between behavioral and MO-VEP measures. However, regression analysis showed that N2 amplitude and latency were significant age predictors. Overall, our results indicate that in motion perception, age-related changes occur in early stages of visual processing, most likely in striate and extrastriate visual cortices.
COBISS.SI-ID: 30760921
Background: Although it has been suggested that disturbances in emotion experience and regulation play a central role in the aetiology and psychopathology of schizophrenia spectrum disorders, the phenomenology of emotion experience in schizophrenia remains under-researched. Sampling and Methods: In-depth interviews were conducted twice with each of the 20 participants (firstly at admission and secondly 6 months later). Data collection and analysis were guided by the principles of phenomenological study of lived experience. Results: The emotion experiences described by our participants vary greatly in both quality and intensity, but appear to have a common phenomenology. Anxiety is reported as the basic emotion which buffers, transforms and sometimes supplants all others. Emotions in general are experienced as foreign, unstable and perturbing, thereby contributing greatly to feelings of ambivalence, perplexity and an unstable sense of self in general. Conclusions: The findings of this study have important therapeutic and theoretical implications because they suggest that emotion experiences in schizophrenia spectrum disorders may underlie a wide range of psychopathological phenomena in both the cognitive and social functioning domains. Due to the relatively small sample size and its selection from psychotherapeutic units, the results may not be generalizable to all schizophrenia patients.
COBISS.SI-ID: 31407321
This study investigated the associations between single nucleotide polymorphisms in the neurodevelopmental Disrupted In Schizophrenia 1 ( DISC1 ), neuregulin 1 ( NRG1 ), brain-derived neurotrophic factor ( BDNF )and NOTCH4 genes and the clinical symptoms and the occur- rence of treatment-resistant schizophrenia in the Slovenian population. We included 138 schizophrenia patients, divid- ed into treatment-responsive a nd treatment-resistant group and 94 healthy blood donors. All subjects were genotyped for eight polymorphisms ( DISC1 rs6675281, DISC1 rs821616, NRG1 rs3735781, NRG1 rs3735782, NRG1 rs10503929, NRG1 rs3924999, BDNF rs6265, NOTCH rs367398) and investigated for associations with clinical variables. NOTCH4 rs367398 AA/AG was significantly associated with worse Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression (CGI) score. NOTCH4 rs367398 was not statistically significant- ly associated with the occurrence of treatment-resistant schizophrenia after the correction for multiple testing. Our data indicate that NOTCH4 polymorphism can influ- ence clinical symptoms in Slovenian patients with schizophrenia
COBISS.SI-ID: 31770585