Sensory suppression and increased neuromodulation during actions disrupt memory encoding of unpredictable self-initiated stimuli

Actions modulate sensory processing by attenuating responses to self- compared to externally-generated inputs, which is traditionally attributed to stimulus-specific motor predictions. Yet, suppression has been also found for stimuli merely coinciding with actions, pointing to unspecific processes that may be driven by neuromodulatory systems. Meanwhile, the differential processing for self-generated stimuli raises the possibility of producing effects also on memory for these stimuli, however, evidence remains mixed as to the direction of the effects. Here, we assessed the effects of actions on sensory processing and memory encoding of concomitant, but unpredictable sounds, using a combination of self-generation and memory recognition task concurrently with EEG and pupil recordings. At encoding, subjects performed button presses that half of the time generated a sound (motor-auditory; MA) and listened to passively presented sounds (auditory-only; A). At retrieval, two sounds were presented and participants had to respond which one was present before. We measured memory bias and memory performance by having sequences where either both or only one of the test sounds were presented at encoding, respectively. Results showed worse memory performance — but no differences in memory bias — and attenuated responses and larger pupil diameter for MA compared to A sounds. Critically, the larger the sensory attenuation and pupil diameter, the worse the memory performance for MA sounds. Nevertheless, sensory attenuation did not correlate with pupil dilation. Collectively, our findings suggest that sensory attenuation and neuromodulatory processes coexist during actions, and both relate to disrupted memory for concurrent, albeit unpredictable sounds.

Do You Have a "Strict Purse"? The Routes to Meaning in Metaphor

<p>Theoretically there are two processing systems through which meaning can be found for a given statement: an effortless, associative processing system (meaning retrieval), or an effortful, analytical processing system (meaning construction). The current study investigated whether or not the context in which target (loosely figurative) word-pairs are presented can influence whether a person relies on associative or analytical processing to find their meaning. Participants were presented with target (loosely figurative) novel word-pairs and asked to judge them for meaningfulness. These target novel word-pairs were presented in different contexts: either mixed with clearly meaningful word-pairs or with additional novel word-pairs. By nature, meaning cannot be retrieved for novel word-pairs, so if a novel word-pair is to be found "meaningful," then its meaning must usually be constructed online (via the analytical processing system). Consistent with increased reliance on analytical processing, participants who saw target novel word-pairs mixed with additional novel word-pairs judged them meaningful more often than did participants who saw them mixed with clearly meaningful word-pairs. Participants who saw target novel word-pairs mixed with additional novel word-pairs also had more negative N400s to target novel word-pairs, indicating that they committed more semantic effort to the processing of these (again consistent with analytical processing). Associative processing does not involve attempts to construct new meaning for given word-pairs. Consistent with increased reliance on associative processing, participants who saw target novel word-pairs mixed with clearly meaningful word-pairs judged them meaningful less often than did participants who saw them mixed with additional novel word-pairs. These participants also had less negative N400s to target novel word-pairs, indicating that they committed less semantic effort to the processing of these (again fitting with associative processing). Further evidence for different contexts leading to differential processing of the same target novel word-pairs was provided by examination of wave morphology. Two distinctive patterns of neural activation were found in response to the same target novel word-pairs, differing depending on the context in which these appeared. Overall, the results of the current study were consistent with the hypothesis that context can influence which processing system is relied upon to find meaning for a given statement. This finding challenges contemporary models of meaning construction and metaphor comprehension by showing that context is essential to these processes and needs to be taken into consideration.</p>

Do You Have a "Strict Purse"? The Routes to Meaning in Metaphor

<p>Theoretically there are two processing systems through which meaning can be found for a given statement: an effortless, associative processing system (meaning retrieval), or an effortful, analytical processing system (meaning construction). The current study investigated whether or not the context in which target (loosely figurative) word-pairs are presented can influence whether a person relies on associative or analytical processing to find their meaning. Participants were presented with target (loosely figurative) novel word-pairs and asked to judge them for meaningfulness. These target novel word-pairs were presented in different contexts: either mixed with clearly meaningful word-pairs or with additional novel word-pairs. By nature, meaning cannot be retrieved for novel word-pairs, so if a novel word-pair is to be found "meaningful," then its meaning must usually be constructed online (via the analytical processing system). Consistent with increased reliance on analytical processing, participants who saw target novel word-pairs mixed with additional novel word-pairs judged them meaningful more often than did participants who saw them mixed with clearly meaningful word-pairs. Participants who saw target novel word-pairs mixed with additional novel word-pairs also had more negative N400s to target novel word-pairs, indicating that they committed more semantic effort to the processing of these (again consistent with analytical processing). Associative processing does not involve attempts to construct new meaning for given word-pairs. Consistent with increased reliance on associative processing, participants who saw target novel word-pairs mixed with clearly meaningful word-pairs judged them meaningful less often than did participants who saw them mixed with additional novel word-pairs. These participants also had less negative N400s to target novel word-pairs, indicating that they committed less semantic effort to the processing of these (again fitting with associative processing). Further evidence for different contexts leading to differential processing of the same target novel word-pairs was provided by examination of wave morphology. Two distinctive patterns of neural activation were found in response to the same target novel word-pairs, differing depending on the context in which these appeared. Overall, the results of the current study were consistent with the hypothesis that context can influence which processing system is relied upon to find meaning for a given statement. This finding challenges contemporary models of meaning construction and metaphor comprehension by showing that context is essential to these processes and needs to be taken into consideration.</p>

How Multi-Sensory Animal Embodiment in Virtual Reality Influences Environmental Threat Processing and Conservation Behaviors

Efforts to mitigate environmental threats are often inversely related to the magnitude of casualty, human or otherwise1–3. This “compassion fade” can be explained, in part, by differential processing of large- versus small-scale threats: it is difficult to form empathic connections with unfamiliar masses versus singular victims4. Despite robust findings, little is known about how non-human casualty is processed, and what strategies override this bias. Over four experiments, we show how embodying threatened megafauna – Loggerhead sea turtles (Caretta Caretta) – in virtual reality can offset and reverse compassion fade. After observing compassion fade during exposure to mass non-human casualty in virtual reality (Study 1; N=60), we then tested a custom multi-sensory virtual reality simulation facilitating embodiment of a threatened Loggerhead (Study 2; N=98). Afterwards, a field experiment (Study 3; N=90) testing the simulation with varied number of victims showed embodiment offset compassion fade. Lastly, a fourth study (N=25) found that charitable giving among users embodying threatened wildlife was highest when exposed to one versus many victims, though this effect was reversed if victims were of a different species (Dolphins). The findings demonstrate how animal embodiment in virtual reality alters processing of environmental threats and non-human casualty, thereby influencing biodiversity conservation outcomes.

Intention-based and sensory-based predictions

We inhabit a continuously changing world, where the ability to anticipate future states of the environment is critical for adaptation. Anticipation can be achieved by learning about the causal or temporal relationship between sensory events, as well as by learning to act on the environment to produce an intended effect. Together, sensory-based and intention-based predictions provide the flexibility needed to successfully adapt. Yet it is currently unknown whether the two sources of information are processed independently to form separate predictions, or are combined into a common prediction. To investigate this, we ran an experiment in which the final tone of two possible four-tone sequences could be predicted from the preceding tones in the sequence and/or from the participants’ intention to trigger that final tone. This tone could be congruent with both sensory-based and intention-based predictions, incongruent with both, or congruent with one while incongruent with the other. Trials where predictions were incongruent with each other yielded similar prediction error responses irrespectively of the violated prediction, indicating that both predictions were formulated and coexisted simultaneously. The violation of intention-based predictions yielded late additional error responses, suggesting that those violations underwent further differential processing which the violations of sensory-based predictions did not receive.

Batch effects removal for microbiome data via conditional quantile regression (ConQuR)

Batch effects in microbiome data arise from differential processing of specimens and can lead to spurious findings and obscure true signals. Most existing strategies for mitigating batch effects rely on approaches designed for genomic analysis, failing to address the zero-inflated and over-dispersed microbiome data. Strategies tailored for microbiome data are restricted to association testing, failing to allow other analytic goals such as visualization. We develop the Conditional Quantile Regression (ConQuR) approach to remove microbiome batch effects using a two-part quantile regression model. It is a fundamental advancement in the field because it is the first comprehensive method that accommodates the complex distributions of microbial read counts, and it generates batch-removed zero-inflated read counts that can be used in and benefit all usual subsequent analyses. We apply ConQuR to real microbiome data sets and demonstrate its state-of-the-art performance in removing batch effects while preserving or even amplifying the signals of interest.

Learning from experience: exposure to, attention to, discrimination of, and brain response to faces at 3, 6, and 9 months

Infants learn and develop immensely in the first year of life. They show substantial learning in their ability to use the information provided by faces. Faces are important stimuli in infants‘ world and infants reliably prefer faces over other visual stimuli (Fantz, 1963). While experience likely plays a role in infants‘ early face processing, little is known about how infants‘ natural exposure to faces shapes attention and learning. We use head-mounted infant-perspective cameras to capture infants‘ natural experience with faces. We also measured infants‘ attentional preference for, ability to discriminate between, and electrical brain response to familiar (i.e., female, own-race) and unfamiliar (i.e., male, other-race) face types. Infants‘ face experience was highly homogenous: their primary caregiver‘s face represents the 57% of infants‘ experience and was present in all locations and nearly all contexts. Infants‘ other caregiver represented only 11% of their face experience, but was also highly consistent across location and context. Infants showed greater visual attention to female faces of familiar race at 3 months, but not later. They showed no race preference at any age. At 3 months, infants discriminated all face types except for male own-race faces. At 6 months, infants discriminated all face types. At 9 months infants discriminated all face types except for male other-race faces. Electrical brain response only differentiated male from female faces at 6 months, not at 3 or 9 months; there was no effect of race at any age. This may be due to the immaturity of the early face processing system or differential processing being indexed at later attentional components. Infants‘ overall face exposure, mom face exposure, and attentional preference for female faces predicted female own-race face discrimination at 3 months, accounting for 62% of the variance. Exposure to male faces correlated with attention to male faces and attention to male faces predicted discrimination of male faces at 3 months, accounting for 11% of the variance. At 6 months dad face exposure predicted discrimination of male faces, accounting for 17% of the variance. Infants‘ early experience, particularly to caregivers‘ faces, tunes infants‘ attention to faces, which in turn predicts discrimination.

Learning from experience: exposure to, attention to, discrimination of, and brain response to faces at 3, 6, and 9 months

Infants learn and develop immensely in the first year of life. They show substantial learning in their ability to use the information provided by faces. Faces are important stimuli in infants‘ world and infants reliably prefer faces over other visual stimuli (Fantz, 1963). While experience likely plays a role in infants‘ early face processing, little is known about how infants‘ natural exposure to faces shapes attention and learning. We use head-mounted infant-perspective cameras to capture infants‘ natural experience with faces. We also measured infants‘ attentional preference for, ability to discriminate between, and electrical brain response to familiar (i.e., female, own-race) and unfamiliar (i.e., male, other-race) face types. Infants‘ face experience was highly homogenous: their primary caregiver‘s face represents the 57% of infants‘ experience and was present in all locations and nearly all contexts. Infants‘ other caregiver represented only 11% of their face experience, but was also highly consistent across location and context. Infants showed greater visual attention to female faces of familiar race at 3 months, but not later. They showed no race preference at any age. At 3 months, infants discriminated all face types except for male own-race faces. At 6 months, infants discriminated all face types. At 9 months infants discriminated all face types except for male other-race faces. Electrical brain response only differentiated male from female faces at 6 months, not at 3 or 9 months; there was no effect of race at any age. This may be due to the immaturity of the early face processing system or differential processing being indexed at later attentional components. Infants‘ overall face exposure, mom face exposure, and attentional preference for female faces predicted female own-race face discrimination at 3 months, accounting for 62% of the variance. Exposure to male faces correlated with attention to male faces and attention to male faces predicted discrimination of male faces at 3 months, accounting for 11% of the variance. At 6 months dad face exposure predicted discrimination of male faces, accounting for 17% of the variance. Infants‘ early experience, particularly to caregivers‘ faces, tunes infants‘ attention to faces, which in turn predicts discrimination.

Processing of Naturally Sourced Macroalgal- and Coral-Dissolved Organic Matter (DOM) by High and Low Microbial Abundance Encrusting Sponges

Sponges play a key role in (re)cycling of dissolved organic matter (DOM) and inorganic nutrients in coral reef ecosystems. Macroalgae and corals release different quantities of DOM and at different bioavailabilities to sponges and their microbiome. Given the current coral- to algal-dominance shift on coral reefs, we assessed the differential processing of macroalgal- and coral-DOM by three high and three low microbial abundance (HMA and LMA) encrusting sponge species. We followed the assimilation of naturally sourced 13C- and 15N-enriched macroalgal- and coral-DOM into bulk tissue and into host- versus bacteria-specific phospholipid fatty acids (PLFAs). Additionally, we compared sponge-processing of the two natural DOM sources with 13C- and 15N-enriched laboratory-made diatom-DOM. All investigated sponges utilized all DOM sources, with higher assimilation rates in LMA compared to HMA sponges. No difference was found in carbon assimilation of coral- versus macroalgal-DOM into bulk tissue and host- versus bacteria-specific PLFAs, but macroalgal nitrogen was assimilated into bulk tissue up to eight times faster compared to the other sources, indicating its higher bioavailability to the sponges. Additionally, LMA sponges released significantly more inorganic nitrogen after feeding on macroalgal-DOM. Therefore, we hypothesize that, depending on the abundance and composition of the sponge community, sponges could catalyze reef eutrophication through increased turnover of nitrogen under coral-to-algal regime shifts.