Behavioral Responses Research Articles

The subthalamic nucleus contributes causally to perceptual decision-making in monkeys

The subthalamic nucleus (STN) plays critical roles in the motor and cognitive function of the basal ganglia (BG), but the exact nature of these roles is not fully understood, especially in the context of decision-making based on uncertain evidence. Guided by theoretical predictions of specific STN contributions, we used single-unit recording and electrical microstimulation in the STN of healthy monkeys to assess its causal, computational roles in visual-saccadic decisions based on noisy evidence. The recordings identified subpopulations of STN neurons with distinct task-related activity patterns that related to different theoretically predicted functions. Microstimulation caused changes in behavioral choices and response times that reflected multiple contributions to an ‘accumulate-to-bound’-like decision process, including modulation of decision bounds and evidence accumulation, and to non-perceptual processes. These results provide new insights into the multiple ways that the STN can support higher brain function.

Aggressive behavior as a predictor of home range size: findings from both range-restricted and widespread Darwin’s finch species

AbstractInformation about an animal’s home range (the geographical area in which it accesses resources for survival and reproduction) is vital broadly for understanding animal behavior and specifically for developing conservation management plans. Although personality traits—consistent individual differences in behavior across time and contexts—may affect an animal’s home range size, we still lack a breadth of empirical studies across systems to fully appreciate this influence. Here, we tested the relationship between behavioral responses and home range size in two Darwin’s finch species on Floreana Island: the critically endangered and range-restricted Medium Tree Finch (Camarhynchus pauper) and the common and widespread Small Ground Finch (Geospiza fuliginosa). Using a combination of rapid-assessment assays during both short-term captivity and in the field, we measured exploration and aggressiveness in males from both species. We then used radio telemetry to measure each bird’s home range size over a week-long period. We predicted that (1) fast-exploring individuals would have larger home ranges, and (2) more aggressive individuals would have smaller home ranges. We found that Medium Tree Finches had smaller home ranges than Small Ground Finches, that exploratory behavior was positively correlated with home range size only in Small Ground Finches, and that, in both species, individuals’ aggressiveness was negatively correlated with home range size, whereby the more aggressive individuals occupied smaller home ranges. We conclude that behavioral responses that align with major personality traits can predict home range size, which may provide an important tool for the conservation and management of endangered species when, for example, selecting individuals with different personality profiles for reintroduction.

Dogs distinguish authentic human emotions without being empathic

Several recent studies have investigated how dogs perceive human emotional expressions. They have measured the reactions of dogs when exposed to stimuli presented in different modalities, such as photographs, audio recordings or odor samples, or to humans simulating various emotional situations. In the current study, dog owners were manipulated to genuinely experience emotions of happiness, sadness, and neutrality. We measured how dogs responded to their owners’ authentic emotions in two different natural situations: induction of the emotion through a video clip and training of a new task. Through a detailed analysis of dog behavior in these naturalistic settings, we investigated whether dogs show behavioral responses to genuine human emotions. We found that dogs behaved differently depending on the owner’s emotional state: they gazed and jumped less at owners when they were sad, and their compliance with the ‘sit’ command was also diminished. When owners were happy, dogs performed better in the trained task. These results are discussed in light of how dogs perceive human emotional expressions and the adaptive value of this skill.

Anticipated benefit termination and health care consumption responses: Evidence from a quasi-experiment

This study is among the first attempts to explore the behavioral responses of anticipated preferential treatment retraction from low-income individuals in the context of health insurance. Utilizing a unique quasi-experimental setting in China, we capture health care demand responses to anticipated benefit termination using a difference-in-differences design. We find a significant increase in individuals’ inpatient health care consumption in anticipation of losing generous insurance benefits. We further investigate the increased consumption and the results suggest that it is largely associated with providing necessary treatments. Additionally, we do not find evidence of supplier-induced demand. In terms of heterogeneity, we find that individuals with chronic disease history, more education, and higher income tend to be more responsive in increasing their health care consumption. While policy evaluations usually focus on the effects upon implementation, our findings shed light on the end-of-benefit responses, and the importance of providing education sessions and liquidity support on individuals’ dynamic decision-making, these findings are meaningful in fully evaluating the impact of insurance contractions.

Differential Bunching Impacts Across the Income Distribution: Evidence from Tax Administrative Data

AbstractWe investigate the behavioural responses of individual taxpayers to changes in marginal personal income tax rates applying empirical bunching methodology to tax administrative data from Zambia over the period from 2014 to 2021. We find evidence for excess bunching at the first kink in the tax schedule for all years but less evidence of bunching at the second and third thresholds. While bunching is considerable and behavioural responses are observed to changes in the location of the kinks over time, bunching at reference points (’round-number bunching’) also appears large. Implied elasticities of taxable income are however not remarkable, and comparing actual and estimated counterfactual wage distributions reveal that missed tax revenue arising from the excess bunching is limited. This is consistent with the observed bunching reacting sharply and immediately to changes in the location of the kink points over time, suggesting that observed behavioural change is driven by reporting behaviour rather than real economic responses.

Exploring the intersection of digital and environmental challenges: Understanding their convergence through habitus

This paper explores the intertwined nature of digital and environmental dimensions within Bourdieu’s concept of habitus to address contemporary global challenges. Controversial evidence exists regarding the environmental impact of digitalization, reflecting contrasting theoretical approaches at societal and individual levels. The paper examines how digital practices’ environmental impact depends on usage types, with implications for lifestyles and values. It revises the concept of habitus to encapsulate the complex interaction between digital and environmental fields, facilitating users’ awareness and behavioral responses.

Regulating the system: Development and early implementation of a behavioral escalation response team in pediatric primary care.

Regulating the system: Development and early implementation of a behavioral escalation response team in pediatric primary care.

The Behavioral Responses of Geoffroy’s Spider Monkeys to Drone Flights

Drones are increasingly used for monitoring wildlife, and it is therefore necessary to evaluate their impact on animal behavior. According to the landscape of fear framework, animals assess and respond to perceived risks in their environment by adjusting their behavior and space use to avoid potential threats. Understanding how drones influence risk perception is thus crucial to avoid generating stress and altering the animal’s natural behavior. Geoffroy’s spider monkeys (Ateles geoffroyi) are endangered arboreal primates, but information on their distribution and abundance is scarce throughout their geographical distribution. Drones can aid to rapidly obtain such information, but data of their impact on the monkeys are needed to design surveys that minimize disturbance (i.e., any interference or modification of the natural behavior of the monkeys caused by the presence and operation of drones). Here, we evaluated whether drone flights influenced the following spider monkey behaviors: agonistic displays, self-scratching, whinny vocalizations, feeding, resting, social interactions, and moving. We also evaluated the effect of three flight parameters, flight height (35, 50 m above ground level), speed (2, 4 m/s), and distance to the drone (“close”, “medium”, and “far”) on spider monkey behavior and examined whether repeated exposure to drones resulted in tolerance (i.e., lack of a behavioral response). We found that drone flights influenced only agonistic displays and resting and that the only flight parameter affecting behaviors was the distance between the monkeys and the drone. We found that spider monkeys developed a tolerance to drone flights only for agonistic displays. Based on our results, we suggest that spider monkeys do not perceive drone flights as major sources of disturbance (such as predators) in the short term, and that drone monitoring can be a viable option to study this species if adequate flight protocols are implemented.

Taste enhances the ability to express a preference for a congruent odor in rats.

Foods that make up a typical diet are characterized by a rich set of sensory qualities that are perceived through multiple different modalities. It is well known that multisensory aspects of food are integrated to create our perception of flavor, which in turn affects our behavioral responses to food. However, the principles underlying multisensory integration of flavor-related sensory signals and how they inform perceptual judgments remain poorly understood, partly due to lack of control over flavor experience in human subjects. Here, we used rats as a model to overcome this limitation and tested the hypothesis that taste can enhance discriminability of retronasal odor cues. In a series of two-bottle tests, animals chose between two odorized solutions after learning to associate one of the odors with saccharin. When odors were highly similar, animals showed little preference for the saccharin-associated odor. When adding saccharin to both bottles-rendering one of the solutions' congruent-animals' preference for the saccharin-associated odor was significantly enhanced. No effect of taste was observed when using dissimilar odor pairs or novel taste stimuli. These findings suggest that congruent taste stimuli selectively enhance odor identity representations, aiding in the discriminability of perceptually similar flavors. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Evaluation of behavioral responses to restraint stress in the house mouse (Mus musculus musculus) of wild origin

Stress is a fundamental concept for many areas of animal research. In laboratory rodents, exposure to various stressors results in immediate and postponed behavioral changes that can be measured with standard tests. Less is known about how wild rodents that have not undergone domestication respond to stressors in laboratory settings. This study was aimed at evaluating behavioral responses to restraint stress in male and female wild-derived house mice (Mus musculus musculus). One week after the end of three daily restraint sessions, alterations in mouse behavior were assessed in two tests. In the open field test, stressed mice (n = 23) entered the unprotected central zone less frequently (P < 0.05) and showed increased duration of self-grooming (P < 0.05) compared to controls (n = 23), indicating elevated anxiety. In the forced swim test, most mice (44 out of 46) displayed episodes of behavioral despair, but the influence of stress was insignificant. To characterize baseline performance of wild-derived mice, their behavior was compared to that of a laboratory strain. As compared to C57BL/6 males (n = 10), M. m. musculus males (n = 14) showed significantly greater exploratory activity in the open field and longer latency of the first immobility episode in the forced swim test (P < 0.001). Overall, these findings confirm ecological validity of the widely used animal model of restraint stress and may serve as a basis for future studies.

Estrous cycle-dependent modulation of sexual receptivity in female mice by estrogen receptor beta-expressing cells in the dorsal raphe nucleus

The sexual receptivity of female mice, shown as lordosis response, is mainly regulated by estradiol action on estrogen receptor alpha (ERα) and beta (ERβ), depending on the day of the estrous cycle. Previous studies revealed that ERα in the ventromedial nucleus of the hypothalamus (VMH) plays an essential role in the induction of lordosis on the day of estrus (Day 1). However, the mechanisms of the transition to non-receptive states on the day after estrus (Day 2) are not completely understood. In the present study, we investigated the possible role of ERβ, which is highly expressed in the dorsal raphe nucleus (DRN), in lordosis expression. We found that ERβ-Cre female mice, which were ovariectomized and primed with estradiol and progesterone to mimic the estrous cycle, showed high levels of lordosis on Day 2 when ERβ-expressing DRN (DRN-ERβ+) neuronal activity was chemogenetically suppressed. This finding suggests that excitation of DRN-ERβ+ neurons is necessary for the decline of lordosis on Day 2. Fiber photometry recordings during female-male behavioral interactions revealed that DRN-ERβ+ neuronal activation in response to male intromission was significantly more prolonged on Day 2 compared to Day 1. Chemogenetic over-stimulation of DRN-ERβ+ neurons induced c-Fos expression in brain areas known to be inhibitory for lordosis expression, even though they did not express anterogradely labeled fibers of DRN-ERβ+ cells. These findings collectively suggest that DRN-ERβ+ neuronal excitation serves as an inhibitory modulator and is responsible for the decline in receptivity during non-estrus phases.Significance StatementIn females, switching from a sexually receptive state to a non-receptive phase during the estrous cycle is essential for effective behavioral interactions with males and successful reproduction. Here, we delineate the possible brain regions that regulate the decline in receptive behavioral responses, such as lordosis, from those shown on the day of estrus to those on the day after estrus. We found that excitation of neurons expressing estrogen receptor (ER) β in the midbrain dorsal raphe nucleus is crucial for the suppression of lordosis during the day after estrus. This is contrasted with the facilitatory action of ERα, another type of ER, and provides new insights for understanding the neural basis of the adaptive expression of female reproductive behavior.

The influence of vehicle size on perception and behavior toward drivers

ABSTRACT This study examines the effects of vehicle size on driver impressions and behavioral intentions. Study 1 tested whether vehicle size (large vs. small) affects perceived physical size (height, body shape) through socioeconomic status (SES). We found that large (vs. small) vehicle drivers were perceived as tall (vs. short), and this perception was mediated by the drivers’ estimated SES (but not by body shape). Study 2 focused on aggressive behavioral intentions (e.g. honking) toward other drivers, examining whether the relationship between vehicle size and intention was serially mediated by estimated physical size and traits (aggression, power). Here, large (vs. small) vehicle driver were perceived as tall (heavy) and possessing high power (high aggression), which is related to less (more) aggressive behavioral intention toward the driver. Our study suggests that individuals perceive other drivers’ physical sizes differently, and this perception is associated with differences in behavioral responses toward other drivers.

Dual Approach to Depression: The Combined Efficacy of Intermittent Hypoxia and Fluoxetine in Modulating Behavioral and Inflammatory Responses.

Background/Objectives: Mental disorders pose a significant public health challenge, affecting millions worldwide. Given the limitations of current therapies, many patients experience inadequate responses and adverse effects. Intermittent hypoxia (IH) has demonstrated anxiolytic, antidepressant, and neuroprotective properties in various protocols. This study investigated the effects of acute IH (13% O2, 1 h), fluoxetine (FLX) and their combination on depression-like behavior, serum corticosterone, and inflammatory cytokine levels induced by acute restraint stress in C57BL/6 female mice. Methods: Behavioral assessments included the tail suspension test, forced swim test, and open field test. Results: The combined IH + FLX treatment exhibited a synergistic effect, reducing immobility time and increasing latency time, respectively, in the tail suspension test (46%, p = 0.0014; 73%, p = 0.0033) and forced swim test (56%, p = 0.0082; 48%, p = 0.0322) compared to the ARS group. Biochemical analysis revealed that individual and combined treatments significantly reduced most inflammatory interleukins by up to 96%. Corticosterone levels were reduced by 30% only in the IH group. Conclusions: These findings highlight the potential of a one-hour IH session, particularly when combined with fluoxetine, to alleviate depressive-like behaviors and exert anti-inflammatory effects, suggesting a promising therapeutic approach for depression.

Accurate Machine Learning-based Monitoring of Anesthesia Depth with EEG Recording.

General anesthesia, pivotal for surgical procedures, requires precise depth monitoring to mitigate risks ranging from intraoperative awareness to postoperative cognitive impairments. Traditional assessment methods, relying on physiological indicators or behavioral responses, fall short of accurately capturing the nuanced states of unconsciousness. This study introduces a machine learning-based approach to decode anesthesia depth, leveraging EEG data across different anesthesia states induced by propofol and esketamine in rats. Our findings demonstrate the model's robust predictive accuracy, underscored by a novel intra-subject dataset partitioning and a 5-fold cross-validation method. The research diverges from conventional monitoring by utilizing anesthetic infusion rates as objective indicators of anesthesia states, highlighting distinct EEG patterns and enhancing prediction accuracy. Moreover, the model's ability to generalize across individuals suggests its potential for broad clinical application, distinguishing between anesthetic agents and their depths. Despite relying on rat EEG data, which poses questions about real-world applicability, our approach marks a significant advance in anesthesia monitoring.

Here Comes Revenge: Peer Victimization Relates to Neural and Behavioral Responses to Social Exclusion.

The aim of this study was to examine whether repeated victimization relates to differential processing of social exclusion experiences. It was hypothesized that experiences of repeated victimization would modulate neural processing of social exclusion in the insula, anterior cingulate cortex, and lateral prefrontal cortex. Furthermore, we hypothesized that repeated victimization relates positively to intentions to punish excluders. Exploratively, associations between neural processing and intentions to punish others were examined. The sample consisted of children with known victimization in the past two years (n = 82 (behavioral) / n = 73 (fMRI), 49.4% girls, Mage = 10.6). The participants played Cyberball, an online ball-tossing game, which was manipulated so that in the first block participants were equally included and in the second block they were excluded from play. Victimization was not related to neural activation during social exclusion, although there were indications that victimization may be related to increased insula activation during explicit exclusion. Behaviorally, repeated victimization was related to more intention to punish excluders. Neural activation during social exclusion did not predict intentions to punish excluders, but results tentatively suggested that increased insula activation during social exclusion may be related to increased intentions to punish. Together, these results provide a replication of earlier Cyberball studies and point toward differential processing of social exclusion by children who are victimized.

Distinct medial amygdala oxytocin receptor neurons projections respectively control consolation or aggression in male mandarin voles

The individuals often show consolation to distressed companions or show aggression to the intruders. The circuit mechanisms underlying switching between consolation and aggression remain unclear. In the present study, using male mandarin voles, we identified that two distinct subtypes of oxytocin receptor (OXTR) neurons in the medial amygdala (MeA) projecting to the anterior insula (AI) and ventrolateral aspect of ventromedial hypothalamus (VMHvl) response differently to stressed siblings or unfamiliar intruders using c-Fos or calcium recording. Oxytocin release and activities of PVN neurons projecting to MeA increased upon consoling and attacking. OXTR antagonist injection to the MeA reduced consoling and attacking. Apoptosis, optogenetic or pharmacogenetic manipulation of these two populations of neurons altered behavioral responses to these two social stimuli respectively. Here, we show that two subtypes of OXTR neurons in the MeA projecting to the AI or VMHvl causally control consolation or aggression that may underlie switch between consolation and aggression.

A Multimodal, In Vivo Approach for Assessing Structurally and Phenotypically Related Neuroactive Molecules.

A recently reported behavioral screen in larval zebrafish for phenocopiers of known anesthetics and associated drugs yielded an isoflavone. Related isoflavones have also been reported as GABAA potentiators. From this, we synthesized a small library of isoflavones and incorporated an in vivo phenotypic approach to perform structure-behavior relationship studies of the screening hit and related analogs via behavioral profiling, patch-clamp experiments, and whole brain imaging. This revealed that analogs effect a range of behavioral responses, including sedation with and without enhancing the acoustic startle response. Interestingly, a subset of compounds effect sedation and enhancement of motor responses to both acoustic and light stimuli. Patch clamp recordings of cells with a human GABAA receptor confirmed that behavior-modulating isoflavones modify the GABA signaling. To better understand these molecules' nuanced effects on behavior, we performed whole brain imaging to reveal that analogs differentially effect neuronal activity. These studies demonstrate a multimodal approach to assessing activities of neuroactives.

The telencephalon is a neuronal substrate for systemic inflammatory responses in teleosts via polyamine metabolism

Systemic inflammation elicits sickness behaviors and fever by engaging a complex neuronal circuitry that begins in the preoptic area of the hypothalamus. Ectotherms such as teleost fish display sickness behaviors in response to infection or inflammation, seeking warmer temperatures to enhance survival via behavioral fever responses. To date, the hypothalamus is the only brain region implicated in sickness behaviors and behavioral fever in teleosts. Yet, the complexity of neurobehavioral manifestations underlying sickness responses in teleosts suggests engagement of higher processing areas of the brain. Using in vivo models of systemic inflammation in rainbow trout, we find canonical pyrogenic cytokine responses in the hypothalamus whereas in the telencephalon and the optic tectum il-1b and tnfa expression is decoupled from il-6 expression. Polyamine metabolism changes, characterized by accumulation of putrescine and decreases in spermine and spermidine, are recorded in the telencephalon but not hypothalamus upon systemic injection of bacteria. While systemic inflammation causes canonical behavioral fever in trout, blockade of bacterial polyamine metabolism prior to injection abrogates behavioral fever, polyamine responses, and telencephalic but not hypothalamic cytokine responses. Combined, our work identifies the telencephalon as a neuronal substrate for brain responses to systemic inflammation in teleosts and uncovers the role of polyamines as critical chemical mediators in sickness behaviors.

Scheduled feeding improves behavioral outcomes and reduces inflammation in a mouse model of Fragile X syndrome.

Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by the abnormal expansion of CGG repeats in the fragile X mental retardation 1 (FMR1) gene. Many FXS patients experience sleep disruptions, and we sought to explore these symptoms along with the possible benefits of a scheduled feeding intervention using the Fmr1 knockout (KO) mouse model. These mutants displayed clear evidence for sleep and circadian disturbances including delay in the onset of sleep and fragmented activity rhythms with increases in cycle-to-cycle variability. The Fmr1 KO mice exhibited deficits in their circadian behavioral response to light with reduced masking, longer time to resetting to shifts in the LD cycle, altered synchronization to a skeleton photoperiod and lower magnitude light-induced phase shifts of activity rhythms. Investigation of the retinal input to the surprachiasmatic nucleus (SCN) with the neurotracer cholera toxin (β subunit) and quantification of the light-evoked cFos expression in the SCN revealed an abnormal retinal innervation of the SCN in the Fmr1 KO, providing a possible mechanistic explanation for the observed behavioral deficits. Interestingly, disruptions in social and repetitive behavior correlated with sleep duration and fragmentation. Understanding the nature of the deficits, we decided to apply a scheduled feeding regimen (6-hr/18-hr feed/fast cycle) as a circadian-based strategy to boast circadian rhythms independently of light. This intervention significantly improved the activity rhythms and sleep in the mutants. Strikingly, the scheduled feeding ameliorated social interactions and reduced repetitive behaviors as well as the levels of Interferon-gamma and Interleukin-12 in the Fmr1 KO mutants, suggesting that timed eating may be an effective way to reduce inflammation. Collectively, this work adds support to efforts to develop circadian based interventions to help with symptoms of neurodevelopmental disorders.

A Descriptive Study to Assess Neonatal Stress Behavior Among Preterm Neonates Admitted in NICU, Nehru Hospital, PGIMER, Chandigarh

Background Preterm neonates are repeatedly exposed to many stressors in initial days of life such as environmental stressor (light and noise) and caregiver interventions (weighing, oral and tracheal suctioning, drawing blood samples, etc.). If preterm neonates’ stress is not recognized and left untreated, there may be long-term effects. Objective To assess the neonatal stress behavior among preterm neonates admitted in neonatal intensive care unit (NICU), Nehru Hospital, PGIMER, Chandigarh. Methodology A descriptive study was conducted to assess neonatal stress behavior among preterm neonates admitted in NICU, Nehru Hospital, PGIMER, Chandigarh. Ethical clearance was taken from Institutional Ethics Committee of PGIMER, Chandigarh. Total 100 participants admitted in NICU during the period of July–December 2022 were enrolled for the study using consecutive sampling technique. Data was collected by interviewing mother using interview schedule. It comprised of sociodemographic cum clinical profile of the preterm neonate. Observation was made by using—(a) modified infant positioning assessment tool (IPAT), (b) neonatal stress scale, and (c) preterm neonate’s behavior assessment scale. Results The present study shows that 88% of the preterm neonates show moderate stress and 70% of preterm neonates exhibit suspected abnormal behavioral response in terms of autonomic visceral subsystems, while 54% of the preterm neonates show suspected abnormal behavioral response in terms of state regulation attention interaction subsystem. Conclusion The present study concluded that moderate stress level and suspected abnormal behavioral response were found among hospitalized preterm neonates.