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Biology subjects

Abel, C.

Publications and source records attributed to Abel, C..

4 recordsLinked to original sources

Auditory-motor synchronization determines the use of predictions in music perception

When listening to music, our brain constantly generates predictions about the timing and pitch of upcoming sounds based on the structure of the music. Individual differences in the ability to make such rhythmic and melodic predictions shape music perception. Previous studies show that during rhythmic auditory-motor synchronization tasks, better performance is related to stronger motor system engagement. However, whether individual differences in auditory-motor interactions influence higher-level rhythmic predictions is unknown. Here, we used electroencephalography during a naturalistic music listening task to assess the neural tracking of rhythmic and melodic predictions generated from (short-term) local contextual information and (long-term) experience using the Information Dynamics of Music model. We combined a multivariate temporal response function approach with two behavioral measures of auditory-motor synchronization (whispering and finger tapping). We found that stronger auditory-motor synchronization predicted stronger neural tracking of lower-level temporal aspects of the music signal, i.e. acoustic envelope and note onset. Across participants, higher-level (short- and long-term) predictions were also neurally tracked, with neural tracking stronger for rhythmic than melodic predictions. Importantly, our evidence suggests individual differences in the weighting of musical predictions. Individuals with stronger auditory-motor synchronization showed stronger neural tracking of rhythmic compared to melodic predictions, and this effect was especially pronounced for short-term predictions. Our findings demonstrate that the motor system is critically involved at several processing levels even in purely perceptual music tasks, and pave the way for understanding individual differences in the weighting of rhythmic and melodic predictions during music listening. Significance statementOur ability to make musical predictions affects our perception of music. Understanding individual differences in predictive processing may allow for differential diagnostics and interventions in clinical disorders such as rhythm disorders or hearing impairment. In an electrophysiological study, we found evidence that the motor system is implicated in predictive processes during perception of music. Specifically, we find advanced neural processing of acoustic temporal features and stronger weighting of short- and long-term rhythmic musical predictions in individuals who recruit the motor system more strongly. Likely, in individuals with high compared to low auditory-motor synchronization strength, the motor system facilitates temporal processing at different levels: at the level of acoustic temporal structure processing, and at higher-level processing of rhythmic musical predictions.

neuroscience↗

Sugar Signaling Induces Dynamic Changes during Meristem Development in Arabidopsis

Aerial parts of plants originate from pluripotent stem cells in the shoot apical meristem. Their population is maintained via the maintenance regulators WUSCHEL and CLAVATA3 in a negative feed-back loop. Meristem size is dynamic and undergoes a more than 2-fold expansion upon the transition to reproductive growth. The mechanism controlling this doming is largely unknown, but coinciding increased trehalose 6-phosphate and changed meristem size in overexpressing or knockdown lines of TREHALOSE PHOSPHATE SYNTHASE1 suggest a participation of sugar signaling. Here we show that TREHALOSE PHOSPHATE PHOSPHATASEJ is directly regulated by WUSCHEL. Plants with reduced levels of TREHALOSE PHOSPHATE PHOSPHATASEJ in the outer meristem layer are flowering early and its reduction in the late flowering clavata3 mutant, restores wild-type flowering. This is caused by a reduction of mature miR156 and increased expression of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE genes. We demonstrate that these are important for age pathway-induced flowering, in a negative feed-back loop with WUSCHEL downstream of the trehalose 6-phosphate pathway. In summary, our findings demonstrate a dynamic feed-back regulation between central maintenance and flowering time regulators with sugar signaling. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=169 SRC="FIGDIR/small/439483v2_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@988d6eorg.highwire.dtl.DTLVardef@16d469borg.highwire.dtl.DTLVardef@1366ce5org.highwire.dtl.DTLVardef@2753f0_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOSynopsis:C_FLOATNO Schematic illustration of dynamic feedback-regulations between sugar signaling, meristem maintenance and the age pathway of the flowering network in the transition SAM as compared to the vegetative SAM.During vegetative growth SAM maintenance is controlled by spatially separated WUS and CLV3 expression in a negative feedback-loop. At floral transition increased activity of the T6P pathway in the SAM uncouples this regulation. This results in an unreported special relocation of WUS expression and involves a transient negative feedback-loop between WUS and SPL4. C_FIG

plant biology↗

Defined diets for freshwater planarians

Planarian flatworms are popular invertebrate models for basic research on stem cell biology and regeneration. These animals are commonly maintained on a diet of homogenized calf liver or boiled egg yolk in the laboratory, introducing a source of uncontrolled experimental variability. Here, we report the development of defined diets, prepared entirely from standardized, commercially sourced ingredients, for the freshwater species Schmidtea mediterranea, Dugesia japonica, and Girardia dorotocephala. These food sources provide an opportunity to test the effects of specific nutritional variables on biological phenomena of interest. Defined diet consumption was not sufficient for growth and only partially induced the increase in stem cell division that normally accompanies feeding, suggesting these responses are not solely determined by caloric intake. While our defined diet formulations do not support long-term planarian maintenance, they do enable delivery of double-stranded RNA for gene knockdown in a manner that provides unique advantages in some experimental contexts. We also present a new approach for preserving tissue integrity during hydrogen peroxide bleaching of liver-fed animals. These tools will empower research on the connections between diet, metabolism, and stem cell biology in the experimentally tractable planarian system.

physiology↗

Improved spatio-temporal measurements of visually evoked fields using optically-pumped magnetometers

Recent developments in performance and practicality of optically pumped magnetometers have enabled new capabilities in non-invasive brain function mapping through magnetoencephalography. In particular the lack of need of cryogenic operating conditions allows for more flexible placement of the sensor heads closer to the brain surface, leading to improved spatial measurement resolution and increased source localisation capabilities. Through the recording of visually evoked brain fields (VEF), we demonstrate that the closer sensor proximity can be further exploited to improve the temporal resolution. We use optically pumped magnetometers (OPMs), and for reference superconducting quantum interference devices (SQUIDs), to measure brain responses to standard flash and pattern reversal stimuli. We find highly reproducible signals with consistency across multiple healthy participants, stimulus paradigms and sensor modalities. The temporal resolution advantage of OPMs is manifest in a fourfold improvement of the ratio of magnetic signal peak height to temporal width, compared to SQUIDs. The resulting capability of improved spatio-temporal signal tracing is illustrated by simultaneous vector recordings of VEFs in the primary (V1) and associative (V2) visual cortex, where a time lag on the order of 10-20 ms is consistently found. This paves the way for further studies of spatio-temporal neurophysiological signal tracking in visual stimulus processing and other brain responses with potentially far-reaching consequences for time-critical mapping of functionality in the healthy and pathological brains.

neuroscience↗