The auditory system is highly sensitive to recurring patterns in the acoustic input - even in otherwise unstructured material, such as white noise or random tonal sequences. Electroencephalography (EEG) research revealed a characteristic negative potential to periodically recurring auditory patterns - a response, which has been interpreted as memory trace-related and specific, rather than as a sign of periodicity-driven entrainment. Here, we aim to disentangle these two possible contributions by investigating the influence of a periodic sound sequence's inherent temporal regularity on event-related potentials. Participants were presented continuous sequences of short tones of random pitch, with some sequences containing a recurring pattern, and asked to indicate whether they heard a repetition. Patterns were either spaced equally across the random sequence (isochronous condition) or with a temporal jitter (jittered condition), which enabled us to differentiate between event-related potentials (and thus processing operations associated with a memory trace for a repeated pattern) and the periodic nature of the repetitions. A negative recurrence-related component could be observed independently of temporal regularity, was pattern-specific, and modulated by across trial repetition of the pattern. Critically, isochronous pattern repetition induced an additional early periodicity-related positive component, which started to build up already before the pattern onset and which was elicited undampedly even when the repeated pattern was occasionally not presented. This positive component likely reflects a sensory driven entrainment process that could be the foundation of a behavioural benefit in detecting temporally regular repetitions.

Purpose: Current research supports the effectiveness of mindfulness-based interventions for maladaptive eating behaviors associated with obesity and eating disorders. To investigate potential underlying mechanisms at work, reliable and valid instruments that allow for an exhaustive assessment of the context-specific construct Mindful Eating (ME) are needed. Therefore, the current work aimed to develop a comprehensive inventory reflecting a wide range of ME attitudes and behaviors: The Mindful Eating Inventory (MEI). Methods & Results: Study 1 describes the item pool development for an initial version of the MEI comprising various steps (compilation of items, expert ratings, focus groups and think aloud protocols by laypersons). Within Study 2, the factor structure of this initial version was explored in an online sample of N = 828 participants and the item pool was shortened via a sequential process based on statistical and content-related considerations. Exploratory factor analyses yielded a seven-factor structure. This structure could be confirmed within Study 3 on an independent online sample of N = 612 participants using confirmatory factor analysis. Criterion validity was supported by hypotheses-confirming correlations with eating-specific and global health-relevant outcomes. Conclusion: Our findings demonstrate that the MEI is a valid and reliable (in terms of internal consistency and retest-reliability) tool, which allows for a comprehensive assessment of various ME attitudes and behaviors within one parsimonious inventory. It further enabled us to propose a so far missing, initial scientific operational definition of this eating-specific construct, that may help to advance future research and clinical application by clarifying mechanisms of action.

African weakly electric fish of the mormyrid genus Campylomormyrus generate pulse-type electric organ discharges (EODs) for orientation and communication. Their pulse durations are species-specific and elongated EODs are a derived trait. So far, differential gene expression among tissue-specific transcriptomes across species with different pulses and point mutations in single ion channel genes indicate a relation of pulse duration and electrocyte geometry/excitability. However, a comprehensive assessment of expressed Single Nucleotide Polymorphisms (SNPs) throughout the entire transcriptome of African weakly electric fish, with the potential to identify further genes influencing EOD duration, is still lacking. This is of particular value, as discharge duration is likely based on multiple cellular mechanisms and various genes. Here we provide the first transcriptome-wide SNP analysis of African weakly electric fish species (genus Campylomormyrus) differing by EOD duration to identify candidate genes and cellular mechanisms potentially involved in the determination of an elongated discharge of C. tshokwe. Non-synonymous substitutions specific to C. tshokwe were found in 27 candidate genes with inferred positive selection among Campylomormyrus species. These candidate genes had mainly functions linked to transcriptional regulation, cell proliferation and cell differentiation. Further, by comparing gene annotations between C. compressirostris (ancestral short EOD) and C. tshokwe (derived elongated EOD), we identified 27 GO terms and 2 KEGG pathway categories for which C. tshokwe significantly more frequently exhibited a species-specific expressed substitution than C. compressirostris. The results indicate that transcriptional regulation as well cell proliferation and differentiation take part in the determination of elongated pulse durations in C. tshokwe. Those cellular processes are pivotal for tissue morphogenesis and might determine the shape of electric organs supporting the observed correlation between electrocyte geometry/tissue structure and discharge duration. The inferred expressed SNPs and their functional implications are a valuable resource for future investigations on EOD durations.

1. We generally assume that animals should maximize information acquisition about their environment to make prudent decisions. But this is a naive assumption, as gaining information typically involves costs. <br /> 2. This is especially so in the social context, where interests between interacting partners usually diverge. The arms race involved in mutual assessment is characterized by the attempt to obtain revealing information from a partner while providing only as much information by oneself as is conducive to one's own intentions. <br /> 3. If obtaining information occasions costs in terms of time, energy and risk, animals should be selected to base their decisions on a cost-benefit ratio that takes account of the trade-off between the risk of making wrong choices and the costs involved in information acquisition, processing and use. <br /> 4. In addition, there may be physiological and/or environmental constraints limiting the ability to obtaining, processing and utilizing reliable information. <br /> 5. Here, we discuss recent empirical evidence for the proposition that social decisions are to an important extent based on the costs that result from acquiring, processing, evaluating and storing information. Using examples from different taxa and ecological contexts, we aim at drawing attention to the often neglected costs of information recipience, with emphasis on the potential role of sensory ecology and cognition in social decisions.