Age related differences in the recognition of facial expression: Evidence from EEG event-related brain oscillations

Facial Expression (FE) recognition is a major marker of emotional ability. Behavioral studies show that FE recognition ability decreases with aging. Studying how event-related brain oscillations change with normal aging is important to better understand the underlying mechanisms of emotional processes. The aim of this study is to investigate changes in FE recognition due to normal aging using the EEG-Brain Oscillations approach.Fifteen young and fifteen elderly healthy subjects were included in the study. 15 photographs were used with 5 different FEs (angry, happy, neutral, sad, fearful). After each EEG recording session, subjects were asked to identify the FEs that were presented. Event-related delta, theta and, alpha phase-locking and frequency-band responses were analyzed.In the FE recognition part of the study, young subjects obtained better scores than the elderly subjects. There was a significant result regarding the locationXgroup comparison in the delta response; the young group had a higher delta response than the elderly group over the occipital area. There were significant locationXgroup differences in the theta and alpha phase locking values; the elderly group had higher theta and alpha phase locking values than the young group in the frontal area. Group differences were significant in the theta response and theta phase locking; the elderly individuals' theta response and phase locking values were higher compared to those of the young individuals.In elderly individuals, FE recognition impairment has been observed. It has been shown that the impairment may be characterized by decreased occipital delta responses and phase locking. This can be interpreted to mean that elderly individuals may have developed different brain dynamics as a compensating mechanism since they are not as efficient as young individuals in performing these functions

Event related potentials to mental arithmetic during cold stress

İstanbul Bilim Üniversitesi, Tıp Fakültesi.AMAÇ: Tek başına ve soğuk stres (SS) sırasında Zihinsel aritmetik hesaplamanın (ZA) Go/NoGo paradigması kullanılarak olaya ilişkin beyin potansiyelleri bağlamında incelenmesi. GEREÇ ve YÖNTEM: Gönüllü üniversite öğrencisi 7 deneğin 11 kanaldan EEG kaydı yapıldı. Deneklerin işlem yapmadıkları, soğuk stres altında oldukları, aritmetik işlem yaptıkları ve soğuk stres sırasında aritmetik işlem yaptıkları durumlarda kan basınçları ve kalp atımları ölçüldü. EEG kayıtlar ZA ve ZA +SS koşullarında Go/NoGO paradigması sırasında alındı. Deneklere ekranda 400 ms süre ile aritmetik bir işlem ve bundan 700 ms sonra sonuç gösterildi. Deneklerden, gösterilen sonuç doğru ise düğmeye basmaları yanlış ise basmamaları istendi

Event-related potentials during auditory oddball, and combined auditory oddball-visual paradigms.

İstanbul Bilim Üniversitesi, Tıp Fakültesi.The purpose of the current study was to investigate the properties of a new modification of the classical auditory oddball paradigm (auditory oddballparadigm 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 theoddball 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.

İstanbul Bilim Üniversitesi, Tıp Fakültesi.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

Brain electrical activities of dancers and fast ball sports athletes are different

İstanbul Bilim Üniversitesi, Tıp Fakültesi.Exercise training has been shown not only to influence physical fitness positively but also cognition in healthy and impaired populations. However, some particular exercise types, even though comparable based on physical efforts, have distinct cognitive and sensorimotor features. In this study, the effects of different types of exercise, such as fast ball sports and dance training, on brain electrical activity were investigated. Electroencephalography (EEG) scans were recorded in professional dancer, professional fast ball sports athlete (FBSA) and healthy control volunteer groups consisting of twelve subjects each. In FBSA, power of delta and theta frequency activities of EEG was significantly higher than those of the dancers and the controls. Conversely, dancers had significantly higher amplitudes in alpha and beta bands compared to FBSA and significantly higher amplitudes in the alpha band in comparison with controls. The results suggest that cognitive features of physical training can be reflected in resting brain electrical oscillations. The differences in resting brain electrical oscillations between the dancers and the FBSA can be the result of innate network differences determining the talents and/or plastic changes induced by physical training

Functional and anatomical characterisation of kisspeptin neurons and synaptic connections in KissCre-GFP mice

..