Telensky, P. | bioRxiv Science

bioRxiv2023

Brain map of aging-induced alterations in membrane ganglioside pattern

Recent efforts to develop comprehensive metabolome and proteome brain atlases for animal models have yielded significant progress. However, the ganglioside (GSs) profile of these models remains largely unexplored. As essential components of the brain, GSs play a crucial role in neuronal function. To address this gap in knowledge, we conducted an in-depth analysis of the young and adult rat brain, as well as its major brain regions, using ultra-high performance liquid chromatography and tandem mass spectrometry in positive and negative ion modes. We also analyzed GSs in cerebrospinal fluid (CSF) and serum from matched samples. Our findings indicate a shift in the ratio of a-series to b-series GSs with age, along with region-specific changes accompanied by aging. This could improve our understanding of brain aging and neurodegenerative diseases. Our study complements existing brain atlases of lipidome and protein expression and highlights the importance of further investigating the mechanisms underlying these GSs changes and the potential therapeutic implications of our findings.

neuroscience↗

bioRxiv2020

Skin conductance rise time and amplitude discern between different degrees of emotional arousal induced by affective pictures presented on a computer screen

Skin Conductance Response (SCR) is a phasic change in electric conductivity of the skin, occurring either non-specifically, or in response to a stimulus (event-related, or ER-SCR). It has long been understood that ER-SCR amplitudes are greater when associated with unpleasant or high-arousal stimuli; however, the relationship between emotional valence and arousal to other ER-SCR measures such as ER-SCR latency (interval between stimulus onset and ER-SCR onset) and ER-SCR rise time (interval between ER-SCR onset and peak amplitude) is less well-established. Here, we presented 60 emotive pictures from IAPS and NAPS affective picture systems to a group of 100 young, healthy adults (50 male and 50 female) and recorded their electrodermal activity. We found that higher emotional arousal was associated with greater ER-SCR amplitudes and shorter ER-SCR rise times. Interestingly, while the increase in ER-SCR amplitudes was only observed for a subset of high-arousal stimuli (score 7-9 on a 9 point scale), the effect on ER-SCR rise times was more graded and particularly sensitive to the difference between low (score 1-3) and medium-arousal (score 4-6) categories. Next, we found that while ER-SCR amplitudes were greater in response to unpleasant stimuli (valence score 1-3 on a 9-point scale), none of the ER-SCR measures could distinguish between neutral (score 4-6) and positive stimuli (score 7-9). We suggest that the increase in ER-SCR amplitudes for unpleasant stimuli is primarily driven by the inherent association between unpleasantness and high arousal. In conclusion, we demonstrate that ER-SCR rise time conveys valuable information about emotional arousal and represents a useful complementary measure to ER-SCR amplitude in order to discern between multiple degrees of emotional arousal. Furthermore, this study confirms the cross-cultural validity of the IAPS and NAPS databases in a sample of young adult Czechs.

physiology↗