Visual Cues Research Articles

Measurement of acute postoperative pain intensity in orthopedic trials: a qualitative concept elicitation study.

Pain intensity is an important outcome in clinical trials of surgery because pain relief is important to patients. Currently, recommended scales are the numeric rating scale 0-10 and visual analogue scale. However, these scales allow for considerable influence of individual imagination, previous experience, and coping skills, limiting proficiency in comparative clinical trials. We aimed to explore postoperative expressions of "how much it hurts"-the first step to improve pain intensity measurement. This was a qualitative study using inductive content analysis: words and visual cues describing pain intensity were collected from (i) existing pain intensity measures by search of COSMIN, PubMed, and Google, (ii) patient interviews recorded and transcribed word-for-word, (iii) clinician interviews transcribed likewise, and (iv) 100 patient telephone interviews with notes taken. After familiarization, the collected expressions were labelled inductively in categories and assembled in tables (case and theme-based matrices). Descriptors fell into 12 categories: intensity (slight/strong), evaluative (negligible/unbearable), cognitive impact (distracting/can be ignored), activity impact (limits some/all activity), sleep impact (can/cannot sleep), examples (like stubbing a toe), physical signs (crying/writhing), associated symptoms (nauseating/tiring), treatment (ice helps/need morphine), affective (annoying/dreadful), discriminative (aching/piercing), and general recovery (hindering recovery/functional interference). Many visual cues were also identified. Literature and recorded interviews gave rise to the categories, and telephone interviews found saturation, providing no further categories. Pain intensity is expressed by terms that fall into 12 categories and by a variety of graphic elements. This advances development of a patient-reported outcome measure of pain intensity for orthopedic trials.

Utilizing Video Feedback for Effective Motor Skill Learning in Online Physical Education

ABSTRACT Video feedback is a commonly recommended tool for online physical education (OLPE) instructors. However, there is little evidence to support its effectiveness in motor skill learning. This study investigated the impact of different forms of pedagogical guidance delivered alongside video feedback on the acquisition and retention of two-disc golf skills: the spin putt (SP) and backhand throw (BT). Forty-three college students were randomly assigned to one of the three video feedback groups: visual cue sheet (VCS), self-assessment (SA), or delayed teacher feedback (TF). During four online practice sessions, they trained on the spin putt and backhand throw techniques. Pre-, post-, and retention tests assessed their performance on both skills. The results indicate significant improvements in BT technique at posttest for both SA and VCS groups. All participants exhibited significant gains in SP technique at posttest; however, only the VCS group sustained these improvements for both disc golf skills at the retention test. No significant differences were observed between the groups for both disc golf skills at all three measurements. These findings suggest that video feedback, particularly when combined with in-the-moment guidance like VCS or SA, can effectively enhance motor skill learning in online settings. This result underscores the potential of OLPE to go beyond fitness-based activities and effectively address psychomotor learning standards. Future research should explore the long-term impact of video feedback in OLPE and identify optimal guidance strategies for diverse motor skills and demographics.

Virus-Induced Gene Silencing Simultaneously Exploits ‘Attract and Kill’ Traits in Plants and Insects to Manage Huanglongbing

Abstract The vector-borne disease Huanglongbing (HLB) causes severe economic losses to citrus production worldwide with no available cure. Herein, we applied virus-induced gene silencing technology to engineer citrus that preferentially attracted and specifically killed Diaphorina citri, the vector associated with HLB. We engineered the infectious citrus tristeza virus (CTV-T36) clone to carry three truncated genes. The triple construct (CTV-tAwd-tWnt-tPDS) produces small interfering RNAs (siRNAs) against phytoene desaturase, PDS, to yield a phenotype with visual, olfactory, and gustatory cues that preferentially attracted D. citri. In addition, siRNAs targeted two genes related to flight in D. citri, abnormal wing disc (DcAwd) and wingless (DcWnt), that caused wing malformations and decreased survival in psyllids that fed on plants inoculated with the engineered virus. During two successive generations, D. citri reared on CTV-tAwd-tWnt-tPDS-inoculated plants exhibited higher mortality across life stages as well as reduced fecundity and fertility as compared with those reared on non-infected plants or CTV-wt-inoculated plants. Furthermore, CTV-tAwd-tWnt-tPDS-inoculated plants shortened the lifespan of D. citri by more than 20 days. Morphological abnormalities were noted in those adults that did successfully emerge on plants inoculated with CTV-tAwd-tWnt-tPDS, including cocked wings with a bowl-shaped depression and/or a convex shape. Phloem sap from CTV-tAwd-tWnt-tPDS-inoculated plants decreased the survival of D. citri adults, confirming that siRNAs were present in the sap of these plants. Collectively, we provide proof of concept for a novel variant of the attract-and-kill method where the cultivated crop is potentially transformed into a hyper-attractive population and transmission sink for a phytopathogen vector.

A song for Pelagibacter. Using creative improvisation as a tool for novel science communication through the Ocean Science Jam

Sharing complex oceanic research in an accessible way with the public is being identified by scientific institutions, universities, governmental departments, and NGOs as a critical intervention in promoting better engagement with the sea. Art–science collaborations play an integral role in this. Traditionally, these involve pairing artists and marine scientists to work on a project which is then presented to an audience. Increasingly however more interactive relationships with the public are being seen as a beneficial way to merge art and scientific data. The Ocean Science Jam is such a project that brings musicians, artists, dancers, performers, and the public together to respond creatively in real time to visual and audio cues based on a theme related to marine scientists’ work. By mixing creativity with science in an integrative way the Ocean Science Jam not only acts as tool for public communication but also opens new ways for scientific data to be interpreted by non-scientists. This paper will explore this initiative from design to delivery highlighting the results of facilitating with the public moments where new responses to ocean science can be created through art. It will do so by combining the reflections of the creator of the Ocean Science Jam as well as feedback from the scientists and public who have participated. It will argue for the benefits of using improvisation and artistic co-creation for developing moments of embodied oceanic exchange and connection.

Category-Sensitive Age-Related Shifts Between Prosodic and Semantic Dominance in Emotion Perception Linked to Cognitive Capacities.

Prior research extensively documented challenges in recognizing verbal and nonverbal emotion among older individuals when compared with younger counterparts. However, the nature of these age-related changes remains unclear. The present study investigated how older and younger adults comprehend four basic emotions (i.e., anger, happiness, neutrality, and sadness) conveyed through verbal (semantic) and nonverbal (facial and prosodic) channels. A total of 73 older adults (43 women, Mage = 70.18 years) and 74 younger adults (37 women, Mage = 22.01 years) partook in a fixed-choice test for recognizing emotions presented visually via facial expressions or auditorily through prosody or semantics. The results confirmed age-related decline in recognizing emotions across all channels except for identifying happy facial expressions. Furthermore, the two age groups demonstrated both commonalities and disparities in their inclinations toward specific channels. While both groups displayed a shared dominance of visual facial cues over auditory emotional signals, older adults indicated a preference for semantics, whereas younger adults displayed a preference for prosody in auditory emotion perception. Notably, the dominance effects observed in older adults for visual and semantic cues were less pronounced for sadness and anger compared to other emotions. These challenges in emotion recognition and the shifts in channel preferences among older adults were correlated with their general cognitive capabilities. Together, the findings underscore that age-related obstacles in perceiving emotions and alterations in channel dominance, which vary by emotional category, are significantly intertwined with overall cognitive functioning. https://doi.org/10.23641/asha.27307251.

Driving Safety and Comfort Enhancement in Urban Underground Interchanges via Driving Simulation and Machine Learning

Urban transportation systems, particularly underground interchanges, present significant challenges for sustainable and resilient urban design due to their complex road geometries and dense traffic signage. These challenges are further compounded by the interaction of diverse road users, which heightens the risk of accidents. To enhance both safety and sustainability, this study integrates advanced driving simulation techniques with machine learning models to improve driving safety and comfort in underground interchanges. By utilizing a driving simulator and 3D modeling, real-world conditions were replicated to design key traffic safety features with an emphasis on sustainability and driver well-being. Critical safety parameters, including speed, acceleration, and pedal use, were analyzed alongside comfort metrics such as lateral acceleration and steering torque. The LightGBM machine learning model was used to classify safety and comfort grades with an accuracy of 97.06%. An important ranking identified entrance signage and deceleration zones as having the greatest impact on safety and comfort, while basic road sections were less influential. These findings underscore the importance of considering visual cues, such as markings and wall color, in creating safer and more comfortable underground road systems. This study’s methodology and results offer valuable insights for urban planners and engineers aiming to design transportation systems that are both safe and aligned with sustainable urban mobility objectives.

The role of motor cortex in motor sequence execution depends on demands for flexibility.

The role of the motor cortex in executing motor sequences is widely debated, with studies supporting disparate views. Here we probe the degree to which the motor cortex's engagement depends on task demands, specifically whether its role differs for highly practiced, or 'automatic', sequences versus flexible sequences informed by external cues. To test this, we trained rats to generate three-element motor sequences either by overtraining them on a single sequence or by having them follow instructive visual cues. Lesioning motor cortex showed that it is necessary for flexible cue-driven motor sequences but dispensable for single automatic behaviors trained in isolation. However, when an automatic motor sequence was practiced alongside the flexible task, it became motor cortex dependent, suggesting that an automatic motor sequence fails to consolidate subcortically when the same sequence is produced also in a flexible context. A simple neural network model recapitulated these results and offered a circuit-level explanation. Our results critically delineate the role of the motor cortex in motor sequence execution, describing the conditions under which it is engaged and the functions it fulfills, thus reconciling seemingly conflicting views about motor cortex's role in motor sequence generation.

Self-awareness from whole-body movements.

Humans can recognize their whole-body movements even when displayed as dynamic dot patterns. The sparse depiction of whole-body movements, coupled with a lack of visual experience watching ourselves in the world, has long implicated non-visual mechanisms to self-action recognition. We aimed to identify the neural systems for this ability. Using general linear modeling and multivariate analyses on human brain imaging data from male and female participants, we first found that cortical areas linked to motor processes, including frontoparietal and primary somatomotor cortices, exhibit greater engagement and functional connectivity when recognizing self-generated versus other-generated actions. Next, we show that these regions encode self-identity based on motor familiarity, even after regressing out idiosyncratic visual cues using multiple regression representational similarity analysis. Last, we found the reverse pattern for unfamiliar individuals: encoding localized to occipito-temporal visual regions. These findings suggest that self-awareness from actions emerges from the interplay of motor and visual processes.Significance Statement: We report for the first time that self-recognition from visual observation of our whole-body actions implicates brain regions associated with motor processes. On functional neuroimaging data, we found greater activity and unique representational patterns in brain areas and networks linked to motor processes when viewing our own actions relative to viewing the actions of others. These findings introduce an important role of motor mechanisms in distinguishing the self from others.

Deafness due to loss of a TRPV channel eliminates mating behavior in Aedes aegypti males

Attraction and mating between male and female animals depend on effective communication between conspecifics. However, in mosquitoes, we have only a rudimentary understanding of the sensory cues and receptors critical for the communication that is essential for reproductive behavior. While it is known that male Aedes aegypti use sound to help them identify females, it is not unclear whether sound detection is absolutely required since other cues such as vision may also participate in mating behavior. To determine the effect of eliminating hearing on mating success, we knocked out the Ae. aegypti TRPVa channel, which is a protein expressed in chordotonal neurons in the Johnston's organ (JO) that respond to sound-induced movements in the antenna. Loss of trpVa eradicated sound-induced responses from the JO, thereby abolishing hearing. Strikingly, mutation of trpVa eliminated mating behavior in males. In contrast, trpVa-null females mated, although this behavior was slightly delayed relative to wild-type females. Males and females produce sounds as they beat their wings at distinct frequencies during flight. Sound mimicking the female wingbeat induced flight, attraction, and copulatory-like behavior in wild-type males without females present, but not in trpVa-null males. Males are known to modulate their wingbeat frequencies before mating in the air, which is a phenomenon referred to as rapid frequency modulation (RFM). We found that RFM was absent in mosquitoes lacking TRPVa. We conclude that the requirement for trpVa and hearing for male reproductive behavior in Aedes is absolute, as mating in the deaf males is eliminated.

Talin and vinculin combine their activities to trigger actin assembly

Focal adhesions (FAs) strengthen their link with the actin cytoskeleton to resist force. Talin-vinculin association could reinforce actin anchoring to FAs by controlling actin polymerization. However, the actin polymerization activity of the talin-vinculin complex is not known because it requires the reconstitution of the mechanical and biochemical activation steps that control the association of talin and vinculin. By combining kinetic and binding assays with single actin filament observations in TIRF microscopy, we show that the association of talin and vinculin mutants, mimicking mechanically stretched talin and activated vinculin, triggers a sequential mechanism in which filaments are nucleated, capped and released to elongate. In agreement with these observations, FRAP experiments in cells co-expressing the same constitutive mutants of talin and vinculin revealed accelerated growth of stress fibers. Our findings suggest a versatile mechanism for the regulation of actin assembly in FAs subjected to various combinations of biochemical and mechanical cues.

Heliconius butterflies use wide-field landscape features, but not individual local landmarks, during spatial learning.

Spatial learning is vital in foraging ecology. Many hymenopteran insects are adept spatial foragers that rely on visual cues contained within broader wide-field scenes for central place foraging from a central nest. By contrast, for butterflies, which lack central nest sites, visual cue use during spatial foraging is less understood. Heliconius butterflies, however, exhibit stable nocturnal roosts, strong site fidelity and a sophisticated capacity for spatial navigation. This study furthers our understanding of Heliconius spatial learning by testing whether H. erato can associate a spatially informative visual cue with artificial feeders. We explored the relative importance of a visual local landmark compared with broader, wide-field visual cues, through experiments with (i) a fixed rewarded feeder with a local landmark; (ii) a mobile rewarded feeder with the landmark as the sole reliable cue; (iii) the same setup while blocking visual access to external landscape features. Our data suggest that Heliconius butterflies learn static feeder locations without relying on a local individual landmark. Instead, we suggest they integrate broader landscape and celestial cues. This suggests that Heliconius butterflies and central place foraging hymenopterans likely share similar visual navigation strategies, using wide-field, low-resolution views rather than focusing on specific individual landmarks.

Felid Scavenging in Forensic Taphonomic Research: An Experimental Approach

Animal scavenging on human remains presents a major challenge at a forensic scene. These lasting changes can influence the interpretation of a post-mortem interval, the overall state of the remains and any associated evidence, impacting the integrity of the scene. Therefore, identifying taphonomic related changes due to animal scavenging is important to understand the post-deposition sequence of events. However, knowing where to look is challenging and animal scavenging studies are difficult to create. Therefore, this study worked in collaboration with zoological institutes in the UK to capture the scavenging changes to horse bone, focussing on the locations of scavenging on bone and the characteristics left. This study focused on large felid (cheetah, lion, tiger, leopard) scavenging, which is less documented in comparison to canine scavenging. This research demonstrated the distribution patterns of tooth activity associated with large felid scavenging is consistent with those reported in the taphonomic literature on lions. Specifically, pits, punctures, scalloping and furrowing were found and characteristics were frequently noted at the borders and flat regions of bones. This study adds to the forensic discussion of scavenging. While focussing on large cats, the work demonstrates anatomical regions that may be affected by scavenging and the visual cues that may help identify animal interaction over human.

Grasp context-dependent uncertainty alters the relative contribution of anticipatory and feedback-based mechanisms in object manipulation

Predictive control within dexterous object manipulation while allowing for the choice of contact points has been shown to employ a predominantly feedback-based force modulation. The anticipation is thought to be facilitated through the internal representation of the object dynamics being integrated and updated on a trial-to-trial basis with the feedback of contact locations on the object. This is as opposed to the classically studied memory representation-based fingertip force control for grasping with pre-selected contact locations. We designed a study to examine this grasp context-dependent asymmetry in sensorimotor integration by introducing binary uncertainty about the grasp type before movement initiation within the framework of motor planning. An inverted T-shaped instrumented object was presented to 24 participants as the manipulandum, and they were asked to reach, grasp, and lift it while minimising the peak roll. We dissociated the planning and the execution phases by pseudo-randomly manipulating the availability of visual contact cues on the object after movement onset. We analysed both derived as well as direct kinetic and kinematic measures of the grasp during the loading phase to understand the anticipatory coordination. Our findings suggest that uncertainty about the grasp context during movement preparation resulted in a shift towards feedback-based mechanisms for grasp force modulation despite the persistence of visual cues.

Ankle torque variance is a better indicator of balance control performance than plantar perceptual sensitivity threshold.

We explored whether ankle torque variability or plantar perceptual threshold explains human balance control more effectively. We hypothesized that ankle torque variance is a better indicator of center of pressure (COP) velocity variance than plantar perceptual sensitivity. Two conditions were tested: loaded (23-kg vest added) and unloaded, as loading should diminish plantar sensitivity and increase COP velocity variability. We created a linear feedback model to assess the noise change in the sensorimotor loop induced by loading. Plantar sensitivity was quantified using a psychophysical approach while participants stood barefoot. A linear motor applied a force impulse on the participant's heel. A "yes-no" method of limits was selected to identify plantar sole sensory thresholds in both conditions. We observed reduced plantar sensitivity in loaded compared with unloaded conditions. In the loaded condition, participants exhibited greater COP velocity variance, with significant positive Pearson's correlations confirming a substantial association between ankle torque and COP velocity variances for both loaded [variance accounted for (VAF): r2 = 44.56%, P = 0.018] and unloaded conditions (VAF: r2 = 58.83%, P = 0.004). No significant correlation existed between COP velocity variance and plantar sensitivity threshold for both loaded (VAF: r2 = 0.002%, P = 0.99) and unloaded conditions (VAF: r2 = 21.81%, P = 0.35). The model confirmed an ∼88% rise in sensorimotor loop noise in the loaded condition. Ankle torque variance assesses the precision of nonperceptual and perceptual detection mechanisms in evaluating whole body motions and the accuracy in converting sensory cues into ankle torque.NEW & NOTEWORTHY Plantar cutaneous information contributes to balance control by modulating motor commands, but plantar perceptual sensitivity is a suboptimal indicator of balance performance. Multiple sensory cues encode whole body dynamics, guiding sensorimotor mechanisms to minimize body sway variability. Ankle torque variance is proposed as a superior measure for explaining balance control performance and evaluating the sensorimotor loop's functioning in balance control.

Vaping and smoking cue reactivity in young adult non-smoking electronic cigarette users: A functional neuroimaging study.

The rapid growth in the use of electronic cigarettes (e-cigarettes) among non-smoking young adults is concerning, as it raises the potential for chronic vaping and nicotine addiction. A key characteristic of drug addiction is the elevated neural response to conditioned drug-related cues (i.e., cue reactivity). Generalized reactivity to both vaping and smoking cues may signify an increased risk for smoking initiation in non-smoking vapers. In this study, we used functional magnetic resonance imaging (fMRI) to evaluate brain responses to vaping and smoking cues in young adult non-smoking vapers. Sixty-six young adult non-smoking vapers underwent functional MRI while viewing visual cues pertaining to vaping, smoking, and nicotine-unrelated unconditioned reward (i.e., food). A priori region-of-interest analysis combined with exploratory whole-brain analysis was performed to characterize neural reactivity to vaping and smoking cues in comparison to food cues. The medial prefrontal cortex and the posterior cingulate cortex, regions that play a key role in drug cue reactivity, showed significantly increased neural response to vaping cues compared to food cues. The posterior cingulate cortex additionally showed increased neural responses to smoking cues compared to food cues. Despite not currently smoking combustible cigarettes, young adult vapers exhibited heightened neural susceptibility to both vaping and smoking cues within brain systems associated with cue reactivity. The findings shed light on the mechanisms underlying nicotine addiction and smoking initiation risk in this critical population and may contribute to the development of science-based interventions and regulatory measures in the future. The escalating vaping prevalence among US non-smoking young adults is alarming, due to its potential ramifications for nicotine addiction development. Nicotine addiction is characterized by elevated neural response to conditioned nicotine-related cues. Using functional neuroimaging, we showed that young adult non-smoking vapers exhibited heightened neural susceptibility to both vaping and smoking cues within brain systems previously associated with cue reactivity. Such cross-reactivity to both types of nicotine cues may serve as the mechanism underlying nicotine addiction and smoking initiation risk in this population. Our findings may contribute to the development of science-based interventions and regulatory measures addressing the vaping epidemic.

A bio-Inspired looming detection for stable landing in unmanned aerial vehicles.

Flying insects, such as flies and bees, have evolved the capability to rely solely on visual cues for smooth and secure landings on various surfaces. In the process of carrying out tasks, micro UAVs may encounter various emergencies, and it is necessary to land safely in complex and unpredictable ground environments, especially when altitude information is not accurately obtained, which undoubtedly poses a significant challenge. Our study draws on the remarkable response mechanism of the Lobula Giant Movement Detector (LGMD) to looming scenarios to develop a novel UAV landing strategy. The proposed strategy does not require distance estimation, making it particularly suitable for payload-constrained micro aerial vehicles. Through a series of experiments, this strategy
has proven to effectively achieve stable and high-performance landings in unknown and complex environments using only a monocular sensor. Furthermore, a novel mechanism to trigger the final landing phase has been introduced, further ensuring the safe and stable touchdown of the drone.&#xD.

Combining visual cues with relaxing music, perfume and ventilation to reduce passenger car sickness: An experimental study

The autonomous, digital, and electric transformation of passenger vehicles is projected to elevate the incidence of motion sickness among occupants. This study investigates the effectiveness of an “anti-motion sickness” system that features dynamic light stimuli to support visual perception of longitudinal motion, combined with relaxing music, perfume and ventilation pulses to enhance user wellbeing. In an experimental design aimed at replicating a realistic passenger drive, fifty-three subjects were tested as front passengers engaged in a gaming activity. Subjective motion sickness ratings were collected throughout the drive, and the development of symptoms was monitored through in-ear physiological measurements, including RR-intervals, core temperature, and oxygen saturation. Post hoc analyses indicated non-significant improvement in subjective assessments of motion sickness. Similarly, physiological measurements did not demonstrate any significant difference across conditions. The tested system was however more effective in mitigating car sickness for low susceptible than for mid-to-high susceptible individuals.

An Empirical Qualitative Investigation into Psychosexual Development in and Sex Education for Autistic Youth: Insights from Autistic and Non-Autistic Young Adults.

The present study was designed to examine autistic and non-autistic young adults' lived experience in psychosexual development and sex education and to solicit recommendations on how to improve sex education programs. Participants included 10 autistic young adults and 10 non-autistic young adults aged 18 to 24 years. The two groups were matched for sex and education level. One-on-one semi-structured interviews were conducted. Participants' responses were analyzed using comparative interpretative phenomenological analysis. Four superordinate themes emerged: (1) "Who am I as a sexual being"; (2) Making sense of psychosexual development; (3) Sources of information; and (4) "Dear developers of sex education programs". Most autistic participants shared feelings of intense anxiety about romantic and sexual relationships, in part due to anticipated difficulties in social communication. Interestingly, although interview questions mostly focused on sex and adolescence, issues surrounding romantic relationships and their links to current self-concept were prominent themes in many autistic participants' responses, suggesting that autism-friendly sex education programs need to address issues related to romance and should target not only adolescents but also young adults. Also, autistic participants learned from peer interactions within the autistic community, highlighting the importance of facilitating peer exchanges and continuous learning beyond completing a program. Regarding delivery format, autistic participants valued concreteness and a mixed-sex small-group setting, and recommended using visual cues, real life examples, and role play. Autistic individuals have unmet psychosexual educational needs. Further research may consider their needs, lived experience, and recommendations when developing new autism-friendly sex education programs.

A slow diaphragmatic breathing intervention for anxiety: How do respiration rate and inhalation/exhalation ratio influence self-reported anxiety?

The primary aim was to investigate how respiration rate and inhalation/exhalation ratio influence self-reported state anxiety during a single slow diaphragmatic breathing exercise session. Eight hundred and twenty-eight participants completed the study at two separate geographical locations (Poland and Spain). Participants performed a 10-min online guided breathing exercise. Respiration rates were sampled from a continuous uniform distribution (ranging from 6 to 12 breaths/min). Similarly, inhalation/exhalation ratios were treated as continuous variables and sampled from a uniform distribution for each participant. An application programed for this experiment displayed visual and auditory cues adjusted for each participant. Before and after the breathing exercise, each participant filled in the Current Anxiety Level Measure questionnaire. Self-trait anxiety was measured with the Clinically Useful Anxiety Outcome Scale. A linear regression model showed that respiration rate, trait anxiety, pre-test anxiety, and nationality (Polish/Spanish) were positively related to post-test anxiety levels. Adding quadratic terms of respiration rate and inhalation/exhalation ratio did not improve model fit. Polish participants exhibited higher post-test anxiety levels compared with the Spanish subsample. Age was negatively associated with post-test anxiety. No significant relationships between inhalation/exhalation ratio and post-test anxiety level were found. Slower respiration rates during a single-session breathing exercise are linearly associated with lower post-test anxiety levels in a large and varied sample. This study is the largest to date and may offer further guidance for predicting expected effect sizes for the relationships between anxiety and respiratory dynamics.

Leptin-activated hypothalamic BNC2 neurons acutely suppress food intake.

Leptin is an adipose tissue hormone that maintains homeostatic control of adipose tissue mass by regulating the activity of specific neural populations controlling appetite and metabolism1. Leptin regulates food intake by inhibiting orexigenic agouti-related protein (AGRP) neurons and activating anorexigenic pro-opiomelanocortin (POMC) neurons2. However, whereas AGRP neurons regulate food intake on a rapid time scale, acute activation of POMC neurons has only a minimal effect3-5. This has raised the possibility that there is a heretofore unidentified leptin-regulated neural population that rapidly suppresses appetite. Here we report the discovery of a new population of leptin-target neurons expressing basonuclin 2 (Bnc2) in the arcuate nucleus that acutely suppress appetite by directly inhibiting AGRP neurons. Opposite to the effect of AGRP activation, BNC2 neuronal activation elicited a place preference indicative of positive valence in hungry but not fed mice. The activity of BNC2 neurons is modulated by leptin, sensory food cues and nutritional status. Finally, deleting leptin receptors in BNC2 neurons caused marked hyperphagia and obesity, similar to that observed in a leptin receptor knockout in AGRP neurons. These data indicate that BNC2-expressing neurons are a key component of the neural circuit that maintains energy balance, thus filling an important gap in our understanding of the regulation of food intake and leptin action.