Conceptual Associations Generate Sensory Predictions.

A crucial ability of the human brain is to learn and exploit probabilistic associations between stimuli to facilitate perception and behavior by predicting future events. Although studies have shown how perceptual relationships are used to predict sensory inputs, relational knowledge is often between concepts rather than percepts (e.g., we learned to associate cats with dogs, rather than specific images of cats and dogs). Here, we asked if and how sensory responses to visual input may be modulated by predictions derived from conceptual associations. To this end we exposed participants of both sexes to arbitrary word-word pairs (e.g., car-dog) repeatedly, creating an expectation of the second word, conditional on the occurrence of the first. In a subsequent session, we exposed participants to novel word-picture pairs, while measuring fMRI BOLD responses. All word-picture pairs were equally likely, but half of the pairs conformed to the previously formed conceptual (word-word) associations, whereas the other half violated this association. Results showed suppressed sensory responses throughout the ventral visual stream, including early visual cortex, to pictures that corresponded to the previously expected words compared with unexpected words. This suggests that the learned conceptual associations were used to generate sensory predictions that modulated processing of the picture stimuli. Moreover, these modulations were tuning specific, selectively suppressing neural populations tuned toward the expected input. Combined, our results suggest that recently acquired conceptual priors are generalized across domains and used by the sensory brain to generate category-specific predictions, facilitating processing of expected visual input.SIGNIFICANCE STATEMENT Perceptual predictions play a crucial role in facilitating perception and the integration of sensory information. However, little is known about whether and how the brain uses more abstract, conceptual priors to form sensory predictions. In our preregistered study, we show that priors derived from recently acquired arbitrary conceptual associations result in category-specific predictions that modulate perceptual processing throughout the ventral visual hierarchy, including early visual cortex. These results suggest that the predictive brain uses prior knowledge across various domains to modulate perception, thereby extending our understanding of the extensive role predictions play in perception.

Updating Contextual Sensory Expectations for Adaptive Behavior.

The brain has the extraordinary capacity to construct predictive models of the environment by internalizing statistical regularities in the sensory inputs. The resulting sensory expectations shape how we perceive and react to the world; at the neural level, this relates to decreased neural responses to expected than unexpected stimuli ("expectation suppression"). Crucially, expectations may need revision as context changes. However, existing research has often neglected this issue. Further, it is unclear whether contextual revisions apply selectively to expectations relevant to the task at hand, hence serving adaptive behavior. The present fMRI study examined how contextual visual expectations spread throughout the cortical hierarchy as we update our beliefs. We created a volatile environment: two alternating contexts contained different sequences of object images, thereby producing context-dependent expectations that needed revision when the context changed. Human participants of both sexes attended a training session before scanning to learn the contextual sequences. The fMRI experiment then tested for the emergence of contextual expectation suppression in two separate tasks, respectively, with task-relevant and task-irrelevant expectations. Effects of contextual expectation emerged progressively across the cortical hierarchy as participants attuned themselves to the context: expectation suppression appeared first in the insula, inferior frontal gyrus, and posterior parietal cortex, followed by the ventral visual stream, up to early visual cortex. This applied selectively to task-relevant expectations. Together, the present results suggest that an insular and frontoparietal executive control network may guide the flexible deployment of contextual sensory expectations for adaptive behavior in our complex and dynamic world.SIGNIFICANCE STATEMENT The world is structured by statistical regularities, which we use to predict the future. This is often accompanied by suppressed neural responses to expected compared with unexpected events ("expectation suppression"). Crucially, the world is also highly volatile and context-dependent: expected events may become unexpected when the context changes, thus raising the crucial need for belief updating. However, this issue has generally been neglected. By setting up a volatile environment, we show that expectation suppression emerges first in executive control regions, followed by relevant sensory areas, only when observers use their expectations to optimize behavior. This provides surprising yet clear evidence on how the brain controls the updating of sensory expectations for adaptive behavior in our ever-changing world.

Removing a single neuron in a vertebrate brain forever abolishes an essential behavior.

The giant Mauthner (M) cell is the largest neuron known in the vertebrate brain. It has enabled major breakthroughs in neuroscience but its ultimate function remains surprisingly unclear: An actual survival value of M cell-mediated escapes has never been supported experimentally and ablating the cell repeatedly failed to eliminate all rapid escapes, suggesting that escapes can equally well be driven by smaller neurons. Here we applied techniques to simultaneously measure escape performance and the state of the giant M axon over an extended period following ablation of its soma. We discovered that the axon survives remarkably long and remains still fully capable of driving rapid escape behavior. By unilaterally removing one of the two M axons and comparing escapes in the same individual that could or could not recruit an M axon, we show that the giant M axon is essential for rapid escapes and that its loss means that rapid escapes are also lost forever. This allowed us to directly test the survival value of the M cell-mediated escapes and to show that the absence of this giant neuron directly affects survival in encounters with a natural predator. These findings not only offer a surprising solution to an old puzzle but demonstrate that even complex brains can trust vital functions to individual neurons. Our findings suggest that mechanisms must have evolved in parallel with the unique significance of these neurons to keep their axons alive and connected.

Spatial and Temporal Context Jointly Modulate the Sensory Response within the Ventral Visual Stream.

Both spatial and temporal context play an important role in visual perception and behavior. Humans can extract statistical regularities from both forms of context to help process the present and to construct expectations about the future. Numerous studies have found reduced neural responses to expected stimuli compared with unexpected stimuli, for both spatial and temporal regularities. However, it is largely unclear whether and how these forms of context interact. In the current fMRI study, 33 human volunteers were exposed to pairs of object stimuli that could be expected or surprising in terms of their spatial and temporal context. We found reliable independent contributions of both spatial and temporal context in modulating the neural response. Specifically, neural responses to stimuli in expected compared with unexpected contexts were suppressed throughout the ventral visual stream. These results suggest that both spatial and temporal context may aid sensory processing in a similar fashion, providing evidence on how different types of context jointly modulate perceptual processing.

Characterization of two novel ammonia transporters, Hiat1a and Hiat1b, in the teleost model system Danio rerio.

Ammonia excretion in fish excretory epithelia is a complex interplay of multiple membrane transport proteins and mechanisms. Using the model system of zebrafish (Danio rerio) larvae, here we identified three paralogues of a novel ammonia transporter, hippocampus-abundant transcript 1 (DrHiat1), also found in most vertebrates. When functionally expressed in Xenopus laevis oocytes, DrHiat1a and DrHiat1b promoted methylamine uptake in a competitive manner with ammonia. In situ hybridization experiments showed that both transporters were expressed as early as the 4-cell stage in zebrafish embryos and could be identified in most tissues 4 days post-fertilization. Larvae experiencing morpholino-mediated knockdown of DrHiat1b exhibited significantly lower whole-body ammonia excretion rates compared with control larvae. Markedly decreased site-specific total ammonia excretion of up to 85% was observed in both the pharyngeal region (site of developing gills) and the yolk sac (region shown to have the highest NH4+ flux). This study is the first to identify DrHiat1b/DrHIAT1 in particular as an important contributor to ammonia excretion in larval zebrafish. Being evolutionarily conserved, these proteins are likely involved in multiple other general ammonia-handling mechanisms, making them worthy candidates for future studies on nitrogen regulation in fishes and across the animal kingdom.

Long-term exposure to fine particulate matter air pollution: An ecological study of its effect on COVID-19 cases and fatality in Germany.

BACKGROUND: COVID-19 is a lung disease, and there is medical evidence that air pollution is one of the external causes of lung diseases. Fine particulate matter is one of the air pollutants that damages pulmonary tissue. The combination of the coronavirus and fine particulate matter air pollution may exacerbate the coronavirus' effect on human health. RESEARCH QUESTION: This paper considers whether the long-term concentration of fine particulate matter of different sizes changes the number of detected coronavirus infections and the number of COVID-19 fatalities in Germany. STUDY DESIGN: Data from 400 German counties for fine particulate air pollution from 2002 to 2020 are used to measure the long-term impact of air pollution. Kriging interpolation is applied to complement data gaps. With an ecological study, the correlation between average particulate matter air pollution and COVID-19 cases, as well as fatalities, are estimated with OLS regressions. Thereby, socioeconomic and demographic covariates are included. MAIN FINDINGS: An increase in the average long-term air pollution of 1 µg/m3 particulate matter PM2.5 is correlated with 199.46 (SD = 29.66) more COVID-19 cases per 100,000 inhabitants in Germany. For PM10 the respective increase is 52.38 (SD = 12.99) more cases per 100,000 inhabitants. The number of COVID-19 deaths were also positively correlated with PM2.5 and PM10 (6.18, SD = 1.44, respectively 2.11, SD = 0.71, additional COVID-19 deaths per 100,000 inhabitants). CONCLUSION: Long-term fine particulate air pollution is suspected as causing higher numbers of COVID-19 cases. Higher long-term air pollution may even increase COVID-19 death rates. We find that the results of the correlation analysis without controls are retained in a regression analysis with controls for relevant confounding factors. Nevertheless, additional epidemiological investigations are required to test the causality of particulate matter air pollution for COVID-19 cases and the severity.

Clinical Presentation of Toddlers With New Intracranial Space-Occupying Lesions: A Case Series.

OBJECTIVE: Intracranial space occupying lesions (ICSOLs) like tumors and abscesses can be life-threatening conditions. It can be especially difficult to diagnose these conditions in toddlers. We aimed to describe symptoms and signs present in a sample of toddlers with ICSOLs. METHODS: We performed a retrospective chart review of 15 toddlers with intracranial tumors, abscesses, or infected cysts. We collected data on the presence of various signs and symptoms on presentation to the emergency department. RESULTS: Eight toddlers (53%) presented with vomiting. A change in behavior was the second most common symptom (6, 40%). Seven children (47%) had motor weakness, and 5 (33%) had ataxia. Eleven of the 12 children with tumors (92%) had documented abnormal neurologic signs on initial physical examination. CONCLUSIONS: Vomiting, a change in behavior, and an abnormal neurologic examination were common signs and symptoms in our sample of toddlers with ICSOLs. An accurate history and appropriate neurologic examination can help physicians make this challenging diagnosis in this age group.

Generation Y: Do millennials need a partner to be happy?

INTRODUCTION: Empirical evidence on Ronald Inglehart's theory of value change shows that subsequent generations show a decline in values of physical and economic security (materialism) in favor of an increase in values of self-expression and autonomy (postmaterialism). METHODS: We investigate in a pre-registered study whether Inglehart's theory also applies to partnership, such that millennials think less that they need a partner to be happy. We used data from the German Socio-Economic Panel (SOEP) study on 4540 17-year-olds from 16 birth cohorts. RESULTS: Results show that adolescents' estimated importance of a romantic partner for personal happiness decreases on average with each subsequent birth cohort. Further significant predictors were socialization and relationship status of the parents, birth year of the father, as well as education and sex of the adolescent. Socioeconomic status and education level of the parents and birth year of the mother were not significant. CONCLUSIONS: Findings provide initial evidence that as society becomes more individualized, even personal happiness is increasingly seen as independent of significant others. Ronald Inglehart's theory of value change, however, seems to have only limited applicability as an explanatory model for this development.

[Awareness and Use of Digital Health Services in Germany: A Cross-sectional Study Representative of the Population]. / Bekanntheit und Nutzung von digitalen Gesundheitsangeboten in Deutschland: eine bevölkerungsrepräsentative Querschnittsuntersuchung.

OBJECTIVES: In light of the current efforts of health policy to implement eHealth, the question arises which sections of the population already use online self-help in order to tailor them to users' needs. The present study aims to determine the differences in the use of health information and psychological online counseling based on socio-demographic variables, health status and previous illnesses. METHODS: The basis for the cross-sectional data analyses using logistic regression analysis was the innovation sample of the German socio-economic panel. Data were collected from September 2016 to February 2017, with 4802 participants aged between 17-95 years. RESULTS: Fifty-five percent of the sample searched for health information on the Internet, while 1.1% had experience with online counseling. Logistic regression analyses showed that online search for information was significantly determined by age (Odds Ratio (OR)=0.96; 95-%-CI=0.96-0.97), gender (OR=1.20; 95-%-CI=1.05-1.36), awareness of Internet therapy (OR=2.57; 95-%-CI=2.20-3.00), experience with psychotherapy (OR=1.40; 95-%-CI=1.16-1.69) and the diagnosis of asthma (OR=1.14; 95-%-CI=1.01-1.29) or stroke (OR=0.66; 95-%-CI=0.52-0.84). Regarding the use of online counseling, awareness of Internet therapy and experience with face-to-face psychotherapy proved to be significant determinants. CONCLUSION: For the first time, a reliable picture has become available of the determinants of the awareness of internet therapy and online self-help utilization among the German public that should enable target-group-specific strategies to improve the care situation.

Suppressed Sensory Response to Predictable Object Stimuli throughout the Ventral Visual Stream.

Prediction plays a crucial role in perception, as prominently suggested by predictive coding theories. However, the exact form and mechanism of predictive modulations of sensory processing remain unclear, with some studies reporting a downregulation of the sensory response for predictable input whereas others observed an enhanced response. In a similar vein, downregulation of the sensory response for predictable input has been linked to either sharpening or dampening of the sensory representation, which are opposite in nature. In the present study, we set out to investigate the neural consequences of perceptual expectation of object stimuli throughout the visual hierarchy, using fMRI in human volunteers. Participants of both sexes were exposed to pairs of sequentially presented object images in a statistical learning paradigm, in which the first object predicted the identity of the second object. Image transitions were not task relevant; thus, all learning of statistical regularities was incidental. We found strong suppression of neural responses to expected compared with unexpected stimuli throughout the ventral visual stream, including primary visual cortex, lateral occipital complex, and anterior ventral visual areas. Expectation suppression in lateral occipital complex scaled positively with image preference and voxel selectivity, lending support to the dampening account of expectation suppression in object perception.SIGNIFICANCE STATEMENT It has been suggested that the brain fundamentally relies on predictions and constructs models of the world to make sense of sensory information. Previous research on the neural basis of prediction has documented suppressed neural responses to expected compared with unexpected stimuli. In the present study, we demonstrate robust expectation suppression throughout the entire ventral visual stream, and underlying this suppression a dampening of the sensory representation in object-selective visual cortex, but not in primary visual cortex. Together, our results provide novel evidence in support of theories conceptualizing perception as an active inference process, which selectively dampens cortical representations of predictable objects. This dampening may support our ability to automatically filter out irrelevant, predictable objects.

Accuracy of food preference predictions in couples.

The goal of this study was to identify and empirically test variables that indicate how well partners in relationships know each other's food preferences. Participants (n = 2,854) lived in the same household and were part of a large, nationally representative panel study in Germany. Each partner independently predicted the other's preferences for several common food items. Results show that predictive accuracy was higher for likes and for extreme and stereotypical preferences as compared to dislikes and for moderate and idiosyncratic preferences. Accuracy was also higher for couples with a high similarity in preferences and with longer relationship duration but was independent of participants' age after controlling for relationship duration. The data also show that relationship duration was accompanied by higher similarity in couples' food preferences. There was a small positive correlation between partner knowledge and both partner similarity and satisfaction with family life, but no correlation between partner knowledge and general life satisfaction. The results reconcile both valence and base-rate accounts of preference prediction accuracy.

Successfully Striving for Happiness: Socially Engaged Pursuits Predict Increases in Life Satisfaction.

Happiness is considered a highly desirable attribute, but whether or not individuals can actively steer their lives toward greater well-being is an open empirical question. In this study, respondents from a representative German sample reported, in text format, ideas for how they could improve their life satisfaction. We investigated which of these ideas predicted changes in life satisfaction 1 year later. Active pursuits per se-as opposed to statements about external circumstances or fortune-were not associated with changes in life satisfaction ( n = 1,178). However, in line with our preregistered hypothesis, among individuals who described active pursuits ( n = 582), those who described social ideas (e.g., spending more time with friends and family) ended up being more satisfied, and this effect was partly mediated by increased socializing. Our results demonstrate that not all pursuits of happiness are equally successful and corroborate the great importance of social relationships for human well-being.

Drosophila TRP and TRPL are assembled as homomultimeric channels in vivo.

Family members of the cationic transient receptor potential (TRP) channels serve as sensors and transducers of environmental stimuli. The ability of different TRP channel isoforms of specific subfamilies to form heteromultimers and the structural requirements for channel assembly are still unresolved. Although heteromultimerization of different mammalian TRP channels within single subfamilies has been described, even within a subfamily (such as TRPC) not all members co-assemble with each other. In Drosophila photoreceptors two TRPC channels, TRP and TRP-like protein (TRPL) are expressed together in photoreceptors where they generate the light-induced current. The formation of functional TRP-TRPL heteromultimers in cell culture and in vitro has been reported. However, functional in vivo assays have shown that each channel functions independently of the other. Therefore, the issue of whether TRP and TRPL form heteromultimers in vivo is still unclear. In the present study we investigated the ability of TRP and TRPL to form heteromultimers, and the structural requirements for channel assembly, by studying assembly of GFP-tagged TRP and TRPL channels and chimeric TRP and TRPL channels, in vivo. Interaction studies of tagged and native channels as well as native and chimeric TRP-TRPL channels using co-immunoprecipitation, immunocytochemistry and electrophysiology, critically tested the ability of TRP and TRPL to interact. We found that TRP and TRPL assemble exclusively as homomultimeric channels in their native environment. The above analyses revealed that the transmembrane regions of TRP and TRPL do not determine assemble specificity of these channels. However, the C-terminal regions of both TRP and TRPL predominantly specify the assembly of homomeric TRP and TRPL channels.

Persons in contexts: The role of social networks and social density for the dynamic regulation of face-to-face interactions in daily life.

Current psychological theories on daily social interactions emphasize individual differences yet are underspecified regarding contextual factors. We aim to extend this research by examining how two context factors shape social interactions in daily life: how many relationships people maintain and how densely people live together. In Study 1, 307 German participants (Mage = 39.44 years, SDage = 14.14) answered up to 20 experience sampling questionnaires regarding their social interactions over 2 days. In Study 2, 313 German participants (Mage = 48.96 years, SDage = 15.54) summarized their daily interactions in daily diaries for 14 days. Participants reported on their social network size and the social density (i.e., household and neighborhood density) of their living situations. Mobile sensing provided additional measures of social interactions and network size. The results showed that participants living in densely populated households transitioned faster from solitude to social interactions but slower from social interactions to solitude. Participants living in dwellings with more homes also transitioned slower from solitude to social interactions. Contrary to the hypothesis, social network size was inconsistently linked with transitions from solitude to social interactions and vice versa. Furthermore, current social desires predicted subsequent social interactions within days, but not across days-irrespective of individuals' social network size or social density. Together the results point out that people live their daily life in social contexts, which contribute to how they engage in social interactions. The findings thus call for a greater integration of contextual factors in personality theories of social interactions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Social dynamics and affect: Investigating within-person associations in daily life using experience sampling and mobile sensing.

Social interactions are crucial to affective well-being. Still, people vary interindividually and intraindividually in their social needs. Social need regulation theories state that mismatches between momentary social desire and actual social contact result in lowered affect, yet empirical knowledge about this dynamic regulation is limited. In a gender- and age-heterogenous sample, German-speaking participants (N = 306, 51% women, Mage = 39.41, range 18-80 years) answered up to 20 momentary questionnaires about social interactions and affect while mobile sensing tracked their conversations, calls, and app usage over 2 days. Combining preregistered and exploratory analyses, we investigated how momentary affect relates to social dynamics, focusing on two states of mismatch between social desire and social contact: social deprivation (i.e., being alone but desiring contact) and social oversatiation (i.e., being in contact but desiring to be alone). We used specification curve analyses to scrutinize the operationalization of these constructs. Social oversatiation was associated with decreased positive affect and increased negative affect. Social deprivation, however, was unrelated to affect. Exploratory multilevel models showed that a higher desire to be alone was consistently associated with decreased affective well-being, whereas a higher desire for social contact was related to increased affective well-being. Mobile sensing data revealed differential association patterns between affect and face-to-face versus digital communication. We discuss implications for social need regulation, related studies on voluntary solitude, and advantages of combining experience sampling and mobile sensing assessments. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Codevelopment of life goals and the Big Five personality traits across adulthood and old age.

Since the new millennium, research in the field of personality development has focused on the stability and change of basic personality traits. Motivational aspects of personality and their longitudinal association with basic traits have received comparably little attention. In this preregistered study, we applied bivariate latent growth curve model to investigated the codevelopment of nine life goals and the Big Five traits. We tested age, perceived control, gender, educational background, and regional socialization as potential moderators of codevelopment. Data came from the German Socio-Economic Panel study (N = 55,040, age range: 18-103 years) and span a study period of 13 years. During this period, the Big Five traits and life goals were assessed four times. Our findings suggest that development in broader life goal domains (e.g., self-fulfillment) is more strongly connected to personality development across the life span, whereas changes in specific goals (e.g., having children) are more closely tied to trait changes during young and middle adulthood. The strongest codevelopment was found between Openness and agentic goals with a focus on personal growth followed by codevelopment between Agreeableness and communal goals. Developmental stage and educational background moderated the codevelopment of Conscientiousness and economic achievement as well as family-related goals. Contrary to the previous research, we found that Neuroticism codeveloped with communal life goals (i.e., having a happy relationship/marriage). Our findings reinforce theoretical frameworks that highlight the role of changing opportunities, constraints, and developmental tasks across adulthood. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Strategies for combating antibiotic resistance in bacterial biofilms.

Biofilms, which are complexes of microorganisms that adhere to surfaces and secrete protective extracellular matrices, wield substantial influence across diverse domains such as medicine, industry, and environmental science. Despite ongoing challenges posed by biofilms in clinical medicine, research in this field remains dynamic and indeterminate. This article provides a contemporary assessment of biofilms and their treatment, with a focus on recent advances, to chronicle the evolving landscape of biofilm research.

Giardia flagellar motility is not directly required to maintain attachment to surfaces.

Giardia trophozoites attach to the intestinal microvilli (or inert surfaces) using an undefined "suction-based" mechanism, and remain attached during cell division to avoid peristalsis. Flagellar motility is a key factor in Giardia's pathogenesis and colonization of the host small intestine. Specifically, the beating of the ventral flagella, one of four pairs of motile flagella, has been proposed to generate a hydrodynamic force that results in suction-based attachment via the adjacent ventral disc. We aimed to test this prevailing "hydrodynamic model" of attachment mediated by flagellar motility. We defined four distinct stages of attachment by assessing surface contacts of the trophozoite with the substrate during attachment using TIRF microscopy (TIRFM). The lateral crest of the ventral disc forms a continuous perimeter seal with the substrate, a cytological indication that trophozoites are fully attached. Using trophozoites with two types of molecularly engineered defects in flagellar beating, we determined that neither ventral flagellar beating, nor any flagellar beating, is necessary for the maintenance of attachment. Following a morpholino-based knockdown of PF16, a central pair protein, both the beating and morphology of flagella were defective, but trophozoites could still initiate proper surface contacts as seen using TIRFM and could maintain attachment in several biophysical assays. Trophozoites with impaired motility were able to attach as well as motile cells. We also generated a strain with defects in the ventral flagellar waveform by overexpressing a dominant negative form of alpha2-annexin::GFP (D122A, D275A). This dominant negative alpha2-annexin strain could initiate attachment and had only a slight decrease in the ability to withstand normal and shear forces. The time needed for attachment did increase in trophozoites with overall defective flagellar beating, however. Thus while not directly required for attachment, flagellar motility is important for positioning and orienting trophozoites prior to attachment. Drugs affecting flagellar motility may result in lower levels of attachment by indirectly limiting the number of parasites that can position the ventral disc properly against a surface and against peristaltic flow.

Unilateral catheter-based renal sympathetic denervation in resistant arterial hypertension shows no blood pressure-lowering effect.

A 68-year-old woman with resistant essential arterial hypertension despite the regular use of four antihypertensive drugs was referred to the catheter-based renal sympathetic denervation. Due to the complicated anatomy, insertion of the guiding catheter into the left renal artery was not stable. Thus, renal denervation of only the right renal artery was performed. Before and after renal denervation, the patient's blood pressure was monitored by home blood pressure (BP) telemonitoring. The average 7-day home BP telemonitoring values before and 1, 2, and 3 months after denervation were 187.1/124.1, 193.3/123.1, 198.3/129.6, and 195.2/128.0 mm Hg. After unilateral renal denervation, no BP decrease occurred. This unique case suggests that unilateral catheter-based renal sympathetic denervation in resistant arterial hypertension shows no BP-lowering effect. Therefore, when treating resistant hypertension by catheter-based renal denervation, it seems advisable to try always to perform an effective bilateral procedure.