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Background Support-giving has emerged as a health-relevant social behavior, such that giving more support is associated with better physical health. However, biological mechanisms by which support-giving and health are linked remain unclear. Whether support-giving uniquely relates to health relative to other psychosocial factors is also an open research question. Purpose Two studies test the hypothesis that support-giving is uniquely (over-and-above other psychosocial factors) related to lower systemic inflammation, a biological correlate of health. Methods Cross-sectional associations of support-giving with markers of systemic inflammation (i.e., interleukin-6 [IL-6], C-reactive protein [CRP]) were examined in two independent samples of midlife adults (Study 1, n = 746; Study 2, n = 350). Results Consistent with hypotheses, giving to more social targets (to family and friends, and also volunteering for various causes), but not receiving support from similar targets, was associated with lower IL-6. In conceptual replication and extension with a different measure of support-giving, higher frequency of support-giving behavior was associated with lower IL-6, even after adjusting for social network size and individual differences in social desirability. There were no associations between support-giving and CRP in either sample. Conclusions Future research needs to establish causality and directly test mechanistic pathways, but together, findings reaffirm the health-relevance of support-giving behavior and shed light on a promising biological mechanism by which such effects may occur.

Humans need social connection to thrive, but how we fulfill this need is not well understood. Numerous theoretical perspectives propose that continual positive experiences with a close other fulfill the need for social connection. Despite popular acceptance for this notion, little research has investigated the consequences of having multiple experiences with a close other. As a first step toward this goal, the current studies assessed whether recalling prior experiences of social connection with a close other alters feelings of satisfaction toward the same person, the implications of such feelings for social desires outside of the lab (Study 1), and possible brain mechanisms related to fulfilling the need for social connection (Study 2). Consistent with hypotheses, recalling experiences increased feelings of satisfaction toward the close other, but not toward an acquaintance. Further, recalling prior experiences uniquely increased the desire for additional social interaction with the close other, compared with others in general. In Study 2, brain regions related to satiety-the ventral striatum (VS) and ventromedial prefrontal cortex (VMPFC)-showed different patterns to recalling prior experiences with a single close other such that VS activity decreased over recalled experiences, while VMPFC activity remained stable. VMPFC activity, but not VS activity, to recalling experiences with a close other was associated with greater feelings of satisfaction. Together, results are consistent with the proposal that positive experiences, particularly with close others, satisfy the need for social connection. Implications for preventing feelings of social disconnection and maintaining social relatonships over time are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

In patients with diabetic kidney disease (DKD), the estimated glomerular filtration rate (eGFR) or creatinine clearance rate (Ccr) is always used as an index of decline in renal function. However, there are few animal models of DKD that could be used to evaluate renal function based on GFR or Ccr. For this reason, it is desirable to develop animal models to assess renal function, which could also be used for the evaluation of novel therapeutic agents for DKD. Therefore, we aimed to develop such animal model of DKD by using spontaneously hypertensive rat (SHR)/NDmcr-cp (cp/cp) rats with the characteristics of obese type 2 diabetes and metabolic syndrome. As a result, we have found that unilateral nephrectomy (UNx) caused a chronic Ccr decline, development of glomerular sclerosis, tubular lesions, and tubulointerstitial fibrosis, accompanied by renal anemia. Moreover, losartan-mixed diet suppressed the Ccr decline in UNx-performed SHR/NDmcr-cp rats (UNx-SHR/cp rats), with improvement in renal anemia and histopathological changes. These results suggest that UNx-SHR/cp rats could be used as a DKD model for evaluating the efficacy of therapeutic agents based on suppression of renal function decline.

Motor behaviors are often planned long before execution but only released after specific sensory events. Planning and execution are each associated with distinct patterns of motor cortex activity. Key questions are how these dynamic activity patterns are generated and how they relate to behavior. Here, we investigate the multi-regional neural circuits that link an auditory “Go cue” and the transition from planning to execution of directional licking. Ascending glutamatergic neurons in the midbrain reticular and pedunculopontine nuclei show short latency and phasic changes in spike rate that are selective for the Go cue. This signal is transmitted via the thalamus to the motor cortex, where it triggers a rapid reorganization of motor cortex state from planning-related activity to a motor command, which in turn drives appropriate movement. Our studies show how midbrain can control cortical dynamics via the thalamus for rapid and precise motor behavior.

Self-enhancement, the tendency to view oneself positively, is a pervasive social motive widely investigated in the psychological sciences. Relatively little is known about the neurocognitive mechanisms underlying this motive, specifically in social-evaluative situations. To investigate whether positive emotion regulation circuitry, circuitry involved in modulating positive affect, relates to the self-enhancement motive in social contexts, we conducted an functional magnetic resonance imaging (fMRI) study in a healthy young adult sample. We hypothesized that self-enhancement indices (state and trait self-esteem) would relate to greater functional connectivity between right ventrolateral prefrontal cortex (RVLPFC), a region implicated in emotion regulation, and the ventral striatum (VS), a region associated with reward-related affect, during a social feedback task. Following social evaluation, participants experienced stable or decreased state self-esteem. Results showed that stable state self-esteem from pre- to post-scan and higher trait self-esteem related to greater RVLPFC–VS connectivity during positive evaluation. Stable-state self-esteem also related to greater RVLPFC–VS connectivity during negative evaluation. Moreover, RVLPFC activation during all types of feedback processing and left VS activation during negative feedback processing was greater for participants with stable-state self-esteem. These findings implicate neurocognitive mechanisms underlying emotion regulation in the self-enhancement motive and highlight a pathway through which self-enhancement may restore feelings of self-worth during threatening situations.

Behavior that helps, supports, or protects others—or prosocial behavior—has emerged as a health-relevant behavior that can promote the giver’s well-being, yet whether prosocial behavior protects against the effects of a major, ongoing chronic stressor warrants further examination. Thus, in the context of the 2020 COVID-19 pandemic, we examined whether two types of behaviors—those enacted to prevent the spread of disease to the self and others (positive health behaviors) and those enacted to promote others’ psychological and financial well-being (prosocial behaviors)—might protect well-being over time. Using a longitudinal survey method, 745 participants (Mage = 62.87 years) reported their engagement in positive health behaviors, prosocial behaviors, and socioemotional well-being (depressive symptoms, anxiety symptoms, loneliness) approximately two months into mandated lockdown orders in the USA. Three months later, participants again reported their well-being. Results showed that greater self-reported positive health behaviors (e.g., wearing a facemask, distancing from others) was related to decreased depressive symptoms over time, whereas greater self-reported prosocial behaviors (e.g., donating time or money, thanking an essential worker) was related to decreased loneliness over time. Neither behavior was related to anxiety symptoms. Together, results suggest that both doing things for the benefit of others and engaging in positive health behaviors protects well-being, even during times of chronic stress. Findings are however limited by the use of self-report measures. Future research should use experimental and behavioral approaches beyond self-report to verify findings. Supplementary Information The online version contains supplementary material available at 10.1007/s42761-021-00095-1.

Social connection may stem from afferent pathways that bring bodily information to the brain and mind. In support of this perspective, research from animals and humans shows that physical warmth causally affects experiences of social connection. However, whether physical warmth affects feelings of social connection and the brain's response to close others remains unknown. In the current study, 42 participants completed an fMRI scan as they viewed images of a close other and strangers while holding warm, cold, and room-temperature objects. Following the scan, participants reported on their feelings of social connection and pleasure in response to the three temperature conditions. Results revealed a specific effect of physical warmth on brain activity to close others as compared with cooler temperatures (both cold and room temperature) and strangers (e.g., in the ventral striatum, middle-insula, ventromedial prefrontal cortex, pregenual cingulate cortex). Cooler temperatures had no effect on brain activity to close others (vs. strangers). Further, physical warmth increased feelings of social connection, even when adjusting for feelings of pleasure, but not vice versa, suggesting physical warmth may have specific effects on feelings of social connection. Results add to an emerging literature on the contribution of physical warmth to social connection and furthers understanding of why and how connecting with others is a basic need for humans. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Social pain is a common experience that has potent implications for health. However, individuals differ in their sensitivity to social pain. Recent evidence suggests that sensitivity to social pain varies according to a biological factor that modulates sensitivity to physical pain: resting (tonic) blood pressure. The current studies extended this evidence by testing whether blood pressure relates to sensitivity to imagined (Study 1: N = 762, 51% female adults) and acute (Study 2, preregistered: N = 204, 57% female adults) experiences of social pain and whether associations extend to general emotional responding (Studies 1–3; Study 3: N = 162, 59% female adults). In line with prior evidence, results showed that higher resting blood pressure was associated with lower sensitivity to social pain. Moreover, associations regarding blood pressure and sensitivity to social pain did not appear to be explained by individual differences in general emotional responding. Findings appear to be compatible with the interpretation that social and physical pain share similar cardiovascular correlates and may be modulated by convergent interoceptive pathways.

The brain plans and executes volitional movements. The underlying patterns of neural population activity have been explored in the context of movements of the eyes, limbs, tongue, and head in nonhuman primates and rodents. How do networks of neurons produce the slow neural dynamics that prepare specific movements and the fast dynamics that ultimately initiate these movements? Recent work exploits rapid and calibrated perturbations of neural activity to test specific dynamical systems models that are capable of producing the observed neural activity. These joint experimental and computational studies show that cortical dynamics during motor planning reflect fixed points of neural activity (attractors). Subcortical control signals reshape and move attractors over multiple timescales, causing commitment to specific actions and rapid transitions to movement execution. Experiments in rodents are beginning to reveal how these algorithms are implemented at the level of brain-wide neural circuits.

Growing evidence suggests that physical warmth and social warmth-feeling socially connected to others-are linked. In particular, thermoregulatory systems that maintain a relatively warm internal body temperature may also support feelings of social connection. However, it is unknown whether and how feelings of physical and social warmth fluctuate together across time in daily life. To this end, the current study examined tympanic temperature, a measure of internal body temperature, and feelings of social connection assessed multiple times a day over 1 week. Consistent with hypotheses, moment-to-moment changes in tympanic temperature covaried with feelings of social connection across assessments. Thus, warmer body temperatures, in the nonfebrile range, were associated with greater feelings of social connection, and cooler body temperatures were associated with lower feelings of social connection. These findings provide further evidence for the link between physical and social warmth and contribute to an understanding of the dynamic fluctuation of affective experience across time. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

We describe a local model for any Singular Riemannian Foliation in a neighbourhood of a closed saturated submanifold of a regular stratum. Moreover we construct a Lie groupoid which controls the transverse geometry of the linear approximation of the Singular Riemannian Foliation around these submanifolds. We also discuss the closure of this Lie groupoid and its Lie algebroid., Comment: We have completely rewritten the introduction,and added new results such asTheorem 1.6 , (about closure of Lie subgroupoids) , Propositions 6.5 and 6.7.(about the Lie algebroid structure of the Lie groupoid that describe the dynamical behavior of Singular Riemannian foliations)

Acute inflammation-induced sickness behavior involves changes in social behavior that are believed to promote recovery. Whether chronic inflammation can influence social behaviors in ways that promote recovery is unknown. In a sample of mothers of a child with cancer, this report explores the relationship between inflammation that accompanies the stress of diagnosis and changes in social network, cancer-related stress, and inflammation across 1 year. Three hypotheses tested whether a) initial levels of stress associate with initial levels of inflammation, b) initial levels of inflammation predict social network changes over time, and c) social network changes over time buffer changes in stress and inflammation over time.Cancer-related stress (Impact of Events Scale), social network (social roles and contacts from the Social Network Inventory), and systemic inflammation (circulating interleukin [IL]-6) were assessed in 120 mothers three times after their child's cancer diagnosis: after diagnosis (T1), 6-month follow-up (T2), and 12-month follow-up (T3).Consistent with predictions, greater cancer-related stress after diagnosis (T1) was associated with higher IL-6 after diagnosis (T1; b = 0.014, standard error [SE] = 0.01, p = .008). In turn, higher IL-6 after diagnosis (T1) was associated with a decrease in social roles over time (T1 ➔ T3; B = -0.030, SE = 0.01, p = .041). Finally, dropping social roles over time (T1 ➔ T3) was associated with decreases in cancer-related stress (B = 25.44, SE = 12.31, p = .039) and slower increases in IL-6 (B = 1.06, SE = 0.52, p = .040) over time.This study provides a first indication that chronic stress-related systemic inflammation may predict changes in social behavior that associate with stress recovery and slower increases in inflammation in the year after a major life stressor.

OBJECTIVE Early experiences of having received maternal warmth predict responses to opportunities to connect with others later in life. However, the understanding of neurochemical mechanisms by which such relationships emerge remains incomplete. Endogenous opioids, involved in social connection in both animals and humans, may contribute to this link. Therefore, the current study examined a) relationships between early maternal warmth and brain and self-report responses to novel social targets (i.e., outcomes that may promote social connection) and b) the effect of the opioid antagonist, naltrexone, on such relationships. METHODS Eighty-two adult participants completed a retrospective report of early maternal warmth. On a second visit, participants were randomized to 50 mg of oral naltrexone (n = 42) or placebo (n = 40), followed by a magnetic resonance imaging scan where functional brain activity in response to images of novel social targets (strangers) was assessed. Approximately 24 hours later, participants reported on their feelings of social connection since leaving the scanner. RESULTS In the placebo condition, greater early maternal warmth was associated with less dorsal anterior cingulate cortex, anterior insula, ventral striatum, and amygdala activity in response to images of novel social targets (r values ≥ -0.360, p values ≤ .031), and greater feelings of social connection (r = 0.524, p < .001) outside of the laboratory. The same relationships, however, were not present in the naltrexone condition. CONCLUSIONS Results highlight relationships between early maternal warmth and responses to the social world at large and suggest that opioids might contribute to social connection by supporting the buffering effects of warm early life experiences on social connection later in life.Trial Registration: Clinical Trials NCT02818036.

Despite the proposed early life origins of attachment style and its implications for risk for psychopathology, little is known about its neurodevelopmental course. Adolescence represents a key transition period when neural substrates of emotion regulation and reward undergo dramatic maturational shifts. Thus, maladaptive coping strategies associated with insecure attachment styles may have an exaggerated effect during adolescence. The current study, therefore, examined the neural correlates of insecure attachment in a diverse sample of adolescents using a frustrative non-reward task (i.e. repeatedly being denied an expected reward). Although there were no significant interactions in the whole-brain activation averaged over the course of the task, the use of complementary analytic approaches (connectivity, change in activation over the course of the task) revealed widespread alterations associated with avoidant attachment during the immediate reaction to, and ensuing recovery from, being denied a reward. Most strikingly, increased avoidant attachment, adjusting for anxious attachment, predicted functional connectivity and change in activity over time in amygdala–prefrontal and frontostriatal networks to reward blocked vs received trials. These patterns were in the opposite direction compared to those exhibited by adolescents lower in avoidant attachment. The findings suggest that negative emotional experiences, such as receiving frustrating feedback, may be uniquely aversive internal experiences for avoidantly attached adolescents and provide preliminary evidence that early coping strategies may persist into adolescence in the form of altered emotion- and reward-related neural patterns.

There is a growing appreciation for the health benefits of giving support, though variability in such behavior exists. Based on the possibility that the dorsomedial (DMPFC) default network subsystem is associated with social thinking and behavior, integrity of this subsystem may facilitate giving support to others. The current study tested associations between DMPFC subsystem connectivity at rest and tendencies related to giving support. During a functional magnetic resonance imaging session, 45 participants completed an emotional social cues task, a resting-state scan and self-report measures of social support. Supportive behavior during the month following the scan was also assessed. Greater DMPFC subsystem connectivity at rest was associated with greater support giving (though not receiving or perceiving support) at the time of the scan and one month later. Results held after adjusting for extraversion. In addition, greater resting-state DMPFC subsystem connectivity was associated with attenuated dorsal anterior cingulate cortex, anterior insula and amygdala activity to others’ negative emotional social cues, suggesting that DMPFC subsystem integrity at rest is also associated with the dampened withdrawal response proposed to facilitate care for others in need. Together, results begin to hint at an additional role for the ‘default’ social brain: giving support to others.

Background There are robust sex differences in the prevalence of depression. Inflammation and anhedonia may play a role in understanding these sex differences. Indeed, sex differences in inflammation-induced neural responses to reward may provide insight into the sex gaps in depression, but no study has examined this question. Methods As such, the current study examined whether there were sex differences in reward-related neural activity (i.e., ventral striatum [VS] activity) in response to an experimental inflammatory challenge. Human participants ( N = 115; 69 female) were randomly assigned to receive either placebo or low-dose endotoxin, which increases inflammation in a safe, time-limited manner. Two hours after receiving placebo or endotoxin (the height of the inflammatory response to endotoxin), participants completed a task in which they anticipated monetary reward in a functional magnetic resonance imaging scanner. Results Results demonstrated that endotoxin (vs. placebo) led to reduced VS activity in anticipation of reward and that there were sex differences in this effect. Specifically, in female participants, endotoxin (vs. placebo) led to decreased VS activity in anticipation of reward, but this effect was not present in male participants. In addition, within the endotoxin condition, decreases in VS activity in anticipation of reward were related to increases in inflammation for female but not male participants. Conclusions These findings may have implications for understanding how inflammation may contribute to sex differences in rates of depression.

Short-term memories link events separated in time, such as past sensation and future actions. Short-term memories are correlated with slow neural dynamics, including selective persistent activity, which can be maintained over seconds. In a delayed response task that requires short-term memory, neurons in the mouse anterior lateral motor cortex (ALM) show persistent activity that instructs future actions. To determine the principles that underlie this persistent activity, here we combined intracellular and extracellular electrophysiology with optogenetic perturbations and network modelling. We show that during the delay epoch, the activity of ALM neurons moved towards discrete end points that correspond to specific movement directions. These end points were robust to transient shifts in ALM activity caused by optogenetic perturbations. Perturbations occasionally switched the population dynamics to the other end point, followed by incorrect actions. Our results show that discrete attractor dynamics underlie short-term memory related to motor planning.

Objective: Acute inflammation-induced sickness behavior involves changes in social behavior that are believed to promote recovery. Whether chronic inflammation can influence social behaviors in ways that promote recovery is unknown. In a sample of mothers of a child with cancer, this report explores the relationship between inflammation that accompanies the stress of diagnosis and changes in social network, cancer-related stress, and inflammation across one year. Three hypotheses were tested, that (1) initial stress would associate with initial inflammation, (2) initial inflammation would predict social changes over time, and (3) social changes over time would buffer stress and inflammation over time. Methods: Cancer-related stress (Impact of Events Scale), social network (social roles and contacts from the Social Network Inventory), and systemic inflammation (circulating IL-6) were assessed in 120 mothers three times after their child’s cancer diagnosis: following diagnosis (T1), 6-month follow-up (T2), and 12-month follow-up (T3). Results: Consistent with predictions, greater cancer-related stress following diagnosis (T1) was associated with higher IL-6 following diagnosis (T1; b=.014, p=.008). In turn, higher IL-6 following diagnosis (T1) was associated with a decrease in social roles over time (T1-->T3; B=-.030, p=.041), particularly peripheral social roles. Finally, dropping social roles over time (T1-->T3) was associated with decreases in cancer-related stress (B=21.83, p=.040) and slower increases in IL-6 (B=.940, p=.036) over time.Conclusions: This study provides a first indication that chronic stress-related systemic inflammation may predict changes in social behavior that associate with stress recovery and slower increases in inflammation in the year following a major life stressor.

Motor behaviors are often planned long before execution, but only released after specific sensory events. Planning and execution are each associated with distinct patterns of motor cortex activity. Key questions are how these dynamic activity patterns are generated and how they relate to behavior. Here we investigate the multi-regional neural circuits that link an auditory ‘go cue’ and the transition from planning to execution of directional licking. Ascending glutamatergic neurons in the midbrain reticular and pedunculopontine nuclei show short-latency and phasic changes in spike rate that are selective for the go cue. This signal is transmitted via the thalamus to the motor cortex, where it triggers a rapid reorganization of motor cortex state from planning-related activity to a motor command, which in turn drives appropriate movement. Our studies show how brainstem structures can control cortical dynamics via the thalamus for rapid and precise motor behavior.

Humans give support, care, and assistance to others on a daily basis. However, the brain mechanisms that set such supportive behavior in motion are unknown. Based on previous findings demonstrating that activity in a portion of the brain’s default network—the dorsomedial prefrontal cortex (DMPFC)—during brief rest primes social thinking and behavior, momentary fluctuations in this brain region at rest may prime supportive responding. To test this hypothesis, 26 participants underwent functional magnetic resonance imaging (fMRI) while they alternated between deciding whether to give support to a close other in financial need, receive support for themselves, and make arbitrary decisions unrelated to support. Decisions were interleaved with brief periods of rest. Results showed that, within participants, spontaneous activity in the DMPFC during momentary periods of rest primed supportive-responding: greater activity in this region at the onset of a brief period of rest predicted, on a trial-by-trial basis, faster decisions to give support to the close other. Thus, activating the DMPFC as soon as our minds are free from external demands to attention may help individuals “default” to support-giving. Implications for understanding the prosocial functions of the resting brain are discussed.

Giving social support to others has emerged as an additional route by which social ties influence health. Thus, giving support to others not only influences the health of the individual receiving support, but also the health of the individual giving the support. However, the neural mechanisms by which giving support leads to health are only beginning to be explored. In hopes of consolidating and guiding future research on giving support and health, the current review considers why, how, and when giving support is health promoting. Special emphasis is placed on neural regions known to contribute to parental care in animals that both reinforce giving support behavior (ventral striatum and septal area) and reduce stress-related responding (e.g., amygdala) to facilitate care. Hypothesized links between neural regions involved in giving support and peripheral physiology (sympathetic nervous system, hypothalamic-pituitary-adrenal axis, and related inflammatory responding) are considered as well as the conditions under which giving support should be most beneficial for health. Finally, the implications of the current perspective for understanding how social relationships, more broadly, contribute to health and suggestions for future directions are offered.

Persistent neural activity maintains information that connects past and future events. Models of persistent activity often invoke reverberations within local cortical circuits, but long-range circuits could also contribute. Neurons in the mouse anterior lateral motor cortex (ALM) have been shown to have selective persistent activity that instructs future actions. The ALM is connected bidirectionally with parts of the thalamus, including the ventral medial and ventral anterior-lateral nuclei. We recorded spikes from the ALM and thalamus during tactile discrimination with a delayed directional response. Here we show that, similar to ALM neurons, thalamic neurons exhibited selective persistent delay activity that predicted movement direction. Unilateral photoinhibition of delay activity in the ALM or thalamus produced contralesional neglect. Photoinhibition of the thalamus caused a short-latency and near-complete collapse of ALM activity. Similarly, photoinhibition of the ALM diminished thalamic activity. Our results show that the thalamus is a circuit hub in motor preparation and suggest that persistent activity requires reciprocal excitation across multiple brain areas.

People who are socially integrated and have strong social ties live happier, longer lives. The link between social connection and well-being is commonly explained in terms of the benefits of receiving care and support from others. However, the benefits of giving care and support to others for the support provider are often overlooked. We review emerging findings that suggest when, why, and how giving support to others provides benefits to the self. We identify possible mechanisms by which these benefits arise and outline boundary conditions that influence such benefits. To gain a richer understanding of the association between social ties and well-being, an important future research direction is to not only consider the support receiver but also emphasize the support provider.

Optogenetics allows manipulations of genetically and spatially defined neuronal populations with excellent temporal control. However, neurons are coupled with other neurons over multiple length scales, and the effects of localized manipulations thus spread beyond the targeted neurons. We benchmarked several optogenetic methods to inactivate small regions of neocortex. Optogenetic excitation of GABAergic neurons produced more effective inactivation than light-gated ion pumps. Transgenic mice expressing the light-dependent chloride channel GtACR1 produced the most potent inactivation. Generally, inactivation spread substantially beyond the photostimulation light, caused by strong coupling between cortical neurons. Over some range of light intensity, optogenetic excitation of inhibitory neurons reduced activity in these neurons, together with pyramidal neurons, a signature of inhibition-stabilized neural networks ('paradoxical effect'). The offset of optogenetic inactivation was followed by rebound excitation in a light dose-dependent manner, limiting temporal resolution. Our data offer guidance for the design of in vivo optogenetics experiments.

Neuronal inactivation is commonly used to assess the involvement of groups of neurons in specific brain functions. Optogenetic tools allow manipulations of genetically and spatially defined neuronal populations with excellent temporal resolution. However, the targeted neurons are coupled with other neural populations over multiple length scales. As a result, the effects of localized optogenetic manipulations are not limited to the targeted neurons, but produces spatially extended excitation and inhibition with rich dynamics. Here we benchmarked several optogenetic silencers in transgenic mice and with viral gene transduction, with the goal to inactivate excitatory neurons in small regions of neocortex. We analyzed the effects of the perturbations in vivo using electrophysiology. Channelrhodopsin activation of GABAergic neurons produced more effective photoinhibition of pyramidal neurons than direct photoinhibition using light-gated ion pumps. We made transgenic mice expressing the light-dependent chloride channel GtACR under the control of Cre-recombinase. Activation of GtACR produced the most potent photoinhibition. For all methods, localized photostimuli produced photoinhibition that extended substantially beyond the spread of light in tissue, although different methods had slightly different resolution limits (radius of inactivation, 0.5 mm to 1 mm). The spatial profile of photoinhibition was likely shaped by strong coupling between cortical neurons. Over some range of photostimulation, circuits produced the “paradoxical effect”, where excitation of inhibitory neurons reduced activity in these neurons, together with pyramidal neurons, a signature of inhibition-stabilized neural networks. The offset of optogenetic inactivation was followed by rebound excitation in a light dose-dependent manner, which can be mitigated by slowly varying photostimuli, but at the expense of time resolution. Our data offer guidance for the design of in vivo optogenetics experiments and suggest how these experiments can reveal operating principles of neural circuits.

Socially warm experiences, when one feels connected to others, have been linked with physical warmth. Opioids, hypothesized to support social bonding with close others and, separately, physical warmth, may underlie both experiences. In order to test this hypothesis, 80 participants were randomly assigned to the opioid antagonist, naltrexone or placebo before neural and emotional responses to social and physical warmth were collected. Social and physical warmth led to similar increases in ventral striatum (VS) and middle-insula (MI) activity. Further, feelings of social connection were positively related to neural activity to social warmth. However, naltrexone (vs placebo) disrupted these effects by (i) reducing VS and MI activity to social and physical warmth, (ii) erasing the subjective experience–brain association to social warmth and (iii) disrupting the neural overlap between social and physical warmth. Results provide additional support for the theory that social and physical warmth share neurobiological, opioid receptor-dependent mechanisms and suggest multiple routes by which social connections may be maintained.

A reliable finding from the physical pain literature is that individuals with higher resting (i.e., tonic) blood pressure experience relatively less pain in response to nociceptive stimuli. Converging lines of evidence suggest that biological factors that influence the experience of physical pain may also relate to social pain. An open question, however, is whether higher blood pressure per se is a biological factor associated with lower sensitivity to social pain. This possible association was tested in three studies. Consistent with prior findings on physical pain, higher resting blood pressure was associated with lower self-reported sensitivity to social pain across individuals (Study 1 r = −.303, Study 2 r = −.262, −.246), even after adjusting for confounding factors related to blood pressure (Study 3 r = −.222). Findings suggest a previously unknown biological correlate of sensitivity to social pain, providing further evidence for possible shared substrates for physical and social pain.

Giving support contributes to the link between social ties and health; however, the neural mechanisms are not known. Giving support in humans may rely on neural regions implicated in parental care in animals. The current studies, therefore, assess the contribution of parental care-related neural regions to giving support in humans and, as a further theoretical test, examine whether the benefits of giving targeted support to single, identifiable individuals in need extend to giving untargeted support to larger societal causes.For study 1 (n = 45, M (SD) age = 21.98 (3.29), 69% females), participants completed a giving support task, followed by an emotional faces task in the functional magnetic resonance imaging scanner. For study 2 (n = 382, M (SD) age = 43.03 (7.28), 52% females), participants self-reported on their giving support behavior and completed an emotional faces task in the functional magnetic resonance imaging scanner.In study 1, giving targeted (versus untargeted) support resulted in greater feelings of social connection and support effectiveness. Furthermore, greater septal area activity, a region centrally involved in parental care in animals, to giving targeted support was associated with less right amygdala activity to an emotional faces task (r = -.297, 95% confidence interval = -.547 to -.043). Study 2 replicated and extended this association to show that self-reports of giving targeted support were associated with less amygdala activity to a different emotional faces task, even when adjusting for other social factors (r = -.105, 95% confidence interval = -.200 to -.011). Giving untargeted support was not related to amygdala activity in either study.Results highlight the unique benefits of giving targeted support and elucidate neural pathways by which giving support may lead to health.

Animals are not simple input-output machines. Their responses to even very similar stimuli are variable. A key, long-standing question in neuroscience is to understand the neural correlates of such behavioral variability. To reveal these correlates, behavior and neural population activity must be related to one another on single trials. Such analysis is challenging due to the dynamical nature of brain function (e.g., in decision making), heterogeneity across neurons and limited sampling of the relevant neural population. By analyzing population recordings from mouse frontal cortex in perceptual decision-making tasks, we show that an analysis approach tailored to the coarse grain features of the dynamics is able to reveal previously unrecognized structure in the organization of population activity. This structure is similar on error and correct trials, suggesting dynamics that may be constrained by the underlying circuitry, is able to predict multiple aspects of behavioral variability and reveals long time-scale modulation of population activity., To explain the neural correlates of behavior and its variability, one must analyze single-trial population dynamics. Here, the authors develop a statistical method that extracts low-dimensional dynamics that explain behavior better than high-dimensional neural activity revealing unexpected structure.

Objective. Giving support contributes to the link between social ties and health, however, the neural mechanisms are not known. Giving support in humans may rely on neural regions implicated in parental care in animals. The current studies, therefore, assess the contribution of parental care-related neural regions to giving support in humans and, as a further theoretical test, examine whether the benefits of giving targeted support to single, identifiable individuals in need extends to giving untargeted support to larger societal causes. Methods. For Study 1 (n = 45, M age = 21.98 (3.29), 69% females), participants completed a giving support task followed by an emotional faces task in the fMRI scanner. For Study 2 (n = 382, M age=43.03 (7.28), 52% females), participants self-reported on their giving support behavior and completed an emotional faces task in the fMRI scanner. Results. In Study 1, giving targeted (vs. untargeted) support resulted in greater feelings of social connection and support effectiveness. Further, greater septal area (SA) activity, a region centrally involved in parental care in animals, to giving targeted support was associated with less right amygdala activity to an emotional faces task (r=-.297, 95% CI=[-.547, -.043]). Study 2 replicated and extended this association to show that self-reports of giving targeted support were associated with less amygdala activity to a different emotional faces task, even when adjusting for other social factors (r=-.105, 95% CI=[-.200, -.011]). Giving untargeted support was not related to amygdala activity in either study.

Giving social support to others has emerged as an additional route by which social ties influence health. Thus, giving support to others not only influences the health of the individual receiving support, but also the health of the individual giving the support. However, the neural mechanisms by which giving support leads to health are only beginning to be explored. In hopes of consolidating and guiding future research on giving support and health, the current review considers why, how, and when giving support is health-promoting. Special emphasis is placed on neural regions known to contribute to parental care in animals that both reinforce giving support behavior (ventral striatum (VS) and septal area (SA)) and reduce stress-related responding (e.g., amygdala) to facilitate care. Hypothesized links between neural regions involved in giving support and peripheral physiology (sympathetic nervous system (SNS), hypothalamic-pituitary-adrenal (HPA) axis, and related inflammatory responding) are considered as well as the conditions under which giving support should be most beneficial for health. Finally, the implications of the current perspective for understanding how social relationships, more broadly, contribute to health and suggestions for future directions are offered.

Self-compassion has been shown to have significant relationships with psychological health and well-being. Despite the increasing growth of research on the topic, no studies to date have investigat...

Social support is a major contributor to the link between social ties and beneficial health outcomes. Research to date has focused on how receiving support from others might be good for us; however, we know less about the health effects of giving support to others. Based on prior work in animals showing that stimulating neural circuitry important for caregiving behavior can reduce sympathetic-related responses to stressors, it is possible that, in humans, giving to others can reduce stressor-evoked sympathetic nervous system responding, which has implications for health outcomes. To test the effect of giving support on the physiological stress response, participants either wrote a supportive note to a friend (support-giving condition) or wrote about their route to school/work (control condition) before undergoing a standard laboratory-based stress task. Physiological responses (heart rate, blood pressure, salivary alpha-amylase, salivary cortisol), and self-reported stress were collected throughout the protocol. In line with hypotheses, support giving (vs. control) reduced sympathetic-related responses (systolic blood pressure and alpha-amylase) to the stressor. No effects of support giving were found on self-reported psychological stress or cortisol levels. Results add to existing knowledge of the pathways by which support giving may lead to health benefits and highlight the contribution of giving to others in the broader social support-health link.

© 2015 APA, all rights reserved). "Heartwarming" social experiences, when one feels interpersonally connected to others, have recently been linked with physical warmth. According to one theory (Panksepp, 1998), "social warmth" and physical warmth may be closely linked because both experiences are supported by similar neurobiological mechanisms; however, the neurochemical substrates underlying this overlap have not been explored. Here, an opioid antagonist, naltrexone, was administered in order to examine the role of opioids, previously shown to alter temperature and social bonding behavior, on perceived thermal intensity, general positive affect, and feelings of social connection from physical warmth. Thirty-one participants took both naltrexone and a placebo and completed a temperature manipulation task (held a warm pack, cold pack, and neutral object) while on each drug. Replicating previous research, holding a warm (vs. a cold or neutral) object increased feelings of social connection. Moreover, blocking opioids reduced this effect. Hence, naltrexone specifically reduced feelings of social connection to holding a warm (vs. neutral) object but not to holding a cold (vs. neutral) object. These results lend further support to the theory that social and physical warmth share neurobiological, opioid receptor dependent mechanisms. (PsycINFO Database Record

The microstructural evolution of pure copper during friction-stir welding was found to be principally influenced by welding temperature. At temperatures below ~0.5 Tm (where Tm is melting point), the microstructure was shown to be essentially determined by continuous recrystallization, leading to significant grain refinement and related material strengthening in the stir zone. In contrast, grain structure development at temperatures above ~0.5 Tm was dominated by discontinuous recrystallization producing a relatively coarse grain structure in the stir zone and giving rise to material softening.

Giving social support to others has emerged as an additional route by which social ties influence health. Thus, giving support to others not only influences the health of the individual receiving support, but also the health of the individual giving the support. However, the neural mechanisms by which giving support leads to health are only beginning to be explored. In hopes of consolidating and guiding future research on giving support and health, the current review considers why, how, and when giving support is health promoting. Special emphasis is placed on neural regions known to contribute to parental care in animals that both reinforce giving support behavior (ventral striatum and septal area) and reduce stress-related responding (e.g., amygdala) to facilitate care. Hypothesized links between neural regions involved in giving support and peripheral physiology (sympathetic nervous system, hypothalamic-pituitary-adrenal axis, and related inflammatory responding) are considered as well as the conditions under which giving support should be most beneficial for health. Finally, the implications of the current perspective for understanding how social relationships, more broadly, contribute to health and suggestions for future directions are offered.