The Effect of Additional Leg Supports in Control of Posture in Sitting

The objective of the study was to investigate the effect of leg supports on the anticipatory and compensatory postural adjustments of sitting subjects exposed to external perturbations in the anterior-posterior direction. Ten young participants received perturbations applied to the upper body while sitting on a stool with an anterior or posterior leg support and when using a footrest. Electromyographic activities of the trunk and leg muscles and center of pressure displacements were recorded and analyzed during the anticipatory and compensatory phases of postural control. Anticipatory activities were observed in the tibialis anterior, biceps femoris, and erector spinae muscles in the anterior leg support condition. Early onset of muscle activity was observed in the tibialis anterior, biceps femoris, rectus femoris, and erector spinae muscles in the posterior leg support condition compared to the feet support condition. Moreover, to maintain balance participants utilized co-contraction of muscles as the main mechanism of balance control in sitting regardless of the availability of the anterior or posterior leg support. There was no effect of a leg support on center of pressure displacements. The outcome of the study provides a background for future investigations of the effect of leg supports on control of balance in sitting when perturbed.

Anticipatory and Anticipated Emotions in Regular and Non-regular Exercisers - A Qualitative Study

Future-oriented emotions could influence our decisions in everyday life and help understand why some individuals are physically active whilst others are not. Current literature distinguishes between two future-oriented emotion constructs: anticipatory and anticipated emotions. While anticipatory emotions are currently experienced emotions about a future event, anticipated emotions refer to the emotions that a person is expected to experience when confronted with a future event. The main aims of the present study were (1) to identify and describe (a) categories of anticipatory emotions experienced before exercise, and (b) categories of anticipated emotions expected to be experienced during and after exercise, and (2) to develop a theoretical model of anticipated emotion categories. Sixteen participants (M age = 26.03, SD = 6.66) were recruited for semi-structured interviews, and their statements were analyzed using principles of the Grounded Theory. In total, 13 different anticipatory and anticipated emotion categories were identified, such as enjoyment, anxiety, pride, self-anger, and relief. Anticipatory emotions seem to reflect the current affective valence of exercising and may be influenced by daily factors. With regards to anticipated emotions, the results show that regular exercisers anticipated also negative emotions such as anxiety, disappointment, and self-anger, and non-regular exercisers also anticipated positive emotions such as enjoyment, pride, and satisfaction. Therefore, future research should not only focus on the valence of future-oriented emotions, but should investigate the possible impact of specific anticipated emotions on exercise behavior. In addition, a theoretical model of anticipated emotion categories in exercise behavior derived from the interviews. The model outlines different categories of anticipated emotions based on appraisal processes. In conclusion, we assume that this developmental process of anticipated emotions may be embedded in a broader, cyclical process within the context of exercising.

Delayed Anticipatory Muscle Activation in Rotator Cuff Tendinopathy

BACKGROUND

Previous research investigating rotator cuff (RC) tendinopathy has usually focused on pathoanatomy. The pathologic response to anticipatory postural adjustments (APAs) has not yet been investigated.

PURPOSE/HYPOTHESIS

To explore changes in APAs as detected by pre-emptive activation of shoulder muscles during ball catching. It was hypothesized that anticipatory muscle activation (AMA) would be present in the unaffected shoulder but delayed or absent in the affected shoulder in patients with RC tendinopathy.

STUDY DESIGN

Controlled laboratory study.

METHODS

This study included 21 RC tendinopathy patients with a mean age of 49.5 years. Patients were required to grab a ball embedded with an electromyography sensor when it dropped on their hand, and surface electromyography signals were recorded from the infraspinatus, upper trapezius, anterior deltoid, and biceps. The trials utilized 2 balls, weighing 200 g and 500 g. Each ball was used in 2 trials, 1 involving a number count preceding the ball drop (predictable) and the other involving a sudden drop (unpredictable). The onsets of AMA between the affected and unaffected limbs were compared.

RESULTS

Regardless of the experimental condition, significantly delayed AMA onsets were identified in all investigated muscles of the affected side compared with those of the unaffected side, except for the biceps muscle in the 500-g predictable trial. For the infraspinatus, the mean onset time in the 200-g predictable trial was -141.0 ± 60.2 ms on the affected side and -211.9 ± 67.1 ms on the unaffected side (P < .001); in the 200-g unpredictable trial this value was -139.5 ± 54.9 ms on the affected side and -199.5 ± 56.2 ms on the unaffected side (P < .001).

CONCLUSION

Delayed AMA was observed in the affected shoulder compared with the unaffected shoulder in patients with RC tendinopathy, not only in the RC muscle but also in the periscapular and upper arm muscles. This may indicate that central hypoexcitability is partly responsible.

CLINICAL RELEVANCE

The basis for RC tendinopathy treatment should not be limited to the tendon pathoanatomy. Delayed AMA around the shoulder joint could provide insight into potential mechanisms related to the central nervous system.

The effect of a textured insole on anticipatory postural adjustments

PURPOSE

To obtain preliminary data on the effect of a textured insole on postural control.

METHODS

Nine healthy subjects were exposed to external perturbations applied to their shoulders while standing with or without a single textured insole. Body weight distribution and bilateral electromyographic activity (EMG) of trunk and leg muscles were recorded. Onsets of EMG activity of muscles were calculated and analyzed within the interval typical for anticipatory postural adjustments.

RESULTS

When a textured insole was provided under one foot, subjects shifted their body weight towards the contralateral foot. With no insole, the anticipatory onsets of EMG activity of the left and right muscles were symmetrical; when a textured insole was used, the EMG onsets of the muscles on the contralateral side of the body were seen earlier as compared to the insole side. This early activation was more pronounced in the trunk muscles (p < 0.05).

CONCLUSIONS

Using a single textured insole under one-foot induced asymmetry of anticipatory onsets of EMG activity in healthy subjects. The outcome highlights the importance of investigating the role of a single textured insole in control of vertical posture and provides a foundation for future studies focussed on improvement of postural control in individuals with body asymmetry due to unilateral weakness.

Prevention and treatment of anticipatory chemotherapy-induced nausea and vomiting in pediatric cancer patients and hematopoietic stem cell recipients: Clinical practice guideline update

This 2021 clinical practice guideline update provides recommendations for preventing anticipatory chemotherapy-induced nausea and vomiting (CINV) in pediatric patients. Recommendations are based on systematic reviews that identified (1) if a history of acute or delayed CINV is a risk factor for anticipatory CINV, and (2) interventions for anticipatory CINV prevention and treatment. A strong recommendation to optimize acute and delayed CINV control in order to prevent anticipatory CINV is made. Conditional recommendations are made for hypnosis, systematic desensitization, relaxation techniques, and lorazepam for the secondary prevention of anticipatory CINV. No recommendation for the treatment of anticipatory CINV can be made.

Lesson-Drawing from New Zealand and Covid-19: The Need for Anticipatory Policy Making

The Covid-19 pandemic has seen most governments worldwide having to think on their feet rather than implementing detailed and well-rehearsed plans. This is notwithstanding the fact that a pandemic was bound to happen, sooner or later (and will happen again). The effectiveness of national responses has varied enormously. Globally, New Zealand has been perceived as setting the gold standard in 'curve crushing', and for a short period achieved Covid-free status. For this achievement, much credit is due to the New Zealand government, especially to Prime Minister, Jacinda Ardern. However, post-lockdown the New Zealand government has encountered a number of Covid policy implementation problems (many of which could have been anticipated). Nevertheless, Covid-19 might still turn out to have been a seismic shock to existing policy processes and policy frames (such as austerity). If so, there are grounds for hope that in the future, governments and voters might be less short-term in their outlook. Perhaps anticipatory, rather than reactive policy making, might become more fashionable?

Wistar Kyoto Rats Display Anhedonia In Consumption but Retain Some Sensitivity to the Anticipation of Palatable Solutions

The Wistar Kyoto (WKY) rat has been proposed as a model of depression-like symptoms. However, anhedonia—a reduction in the response to normatively rewarding events—as a central depression symptom has yet to be fully assessed in this model. We compared WKY rats and Wistar controls, with stress-susceptibility examined by applying mild unpredictable stress to a subset of each group. Anhedonia-like behavior was assessed using microstructural analysis of licking behavior, where mean lick cluster size reflects hedonic responses. This was combined with tests of anticipatory contrast, where the consumption of a moderately palatable solution (4% sucrose) is suppressed in anticipation of a more palatable solution (32% sucrose). WKY rats displayed greatly attenuated hedonic reactions to sucrose overall, although their reactions retained some sensitivity to differences in sucrose concentration. They displayed normal reductions in consumption in anticipatory contrast, although the effect of contrast on hedonic reactions was greatly blunted. Mild stress produced overall reductions in sucrose consumption, but this was not exacerbated in WKY rats. Moreover, mild stress did not affect hedonic reactions or the effects of contrast. These results confirm that the WKY substrain expresses a direct behavioral analog of anhedonia, which may have utility for increasing mechanistic understanding of depression symptoms.

Patients With Obsessive-Compulsive Disorder Exhibit Deficits in Consummatory but Not Anticipatory Pleasure

Background: Reward dysfunctions have been reported in obsessive-compulsive disorder (OCD), which implicates a high possibility of anhedonia for this disease. However, several components of anhedonia, such as consummatory and anticipatory pleasure, has not been substantially studied in OCD patients. Methods: The Chinese version of the Temporal Experience of Pleasure Scale (CV-TEPS) was used to evaluate both the consummatory and anticipatory pleasure in 130 OCD patients, 89 major depressive disorder (MDD) patients, and 95 healthy controls (HCs). The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the Beck Depression Inventory (BDI) were scored for assessing the severity of obsessive and compulsive symptoms and depressive symptoms, respectively. Analyses of covariance (ANCOVA) were used to compare the differences of anhedonia among the three groups with the severity of depression controlled. Regression analyses were also used to analyze the relationship between consummatory and anticipatory pleasure and clinical variables in OCD patients. Results: After controlling for the effect of depression, there were significant differences in TEPS scores among the three groups (p < 0.05). Compared with HCs, OCD patients had lower scores on the consummatory subscale, but not the anticipatory subscale, of the TEPS. MDD patients had lower scores on both the consummatory and anticipatory subscales than HCs. Conclusion: OCD patients exhibit deficits in consummatory but not anticipatory pleasure, which is distinct from MDD patients.

Perspectives of Nurses, Nurse Leaders, and Women Regarding Anticipatory Rounds in the Postpartum Period

OBJECTIVE

To obtain the perspectives of staff nurses, nurse leaders, and women with regard to the relevance and timing of nursing interactions during anticipatory rounds in the postpartum period.

DESIGN

A qualitative descriptive design using focus groups.

SETTING

A hospital with 405 beds that serves a Midwestern U.S. community of approximately 256,000 people.

PARTICIPANTS

A purposive sample of 12 staff nurses, 6 nurse leaders, and 15 women attended a total of 10 focus groups.

METHODS

We conducted 10 semistructured focus groups: 6 with staff nurses, 1 with nurse leaders, and 3 with women. Each participant attended one focus group. Sessions were recorded and transcribed. Investigators independently coded transcripts and identified themes collectively.

RESULTS

Participants identified one overarching theme, Taking the Whole Picture Into Account, and five subthemes that were reflective of relevant nursing interactions: Help With Newborn Feeding, Managing Patient Comfort, Appreciating the Need for Safety, Being There, and Knowing Ahead of Time. Participants agreed that conducting rounds once every 2 to 3 hours was the most appropriate time frame.

CONCLUSION

Participants identified important nursing interactions and their timing. Moreover, anticipatory rounding for women after birth includes more than completion of simple tasks or checklists. These findings indicate beginning evidence for what should occur during anticipatory rounds on the mother-baby unit. Timing of rounds can be flexible based on each woman's unique needs, thus reinforcing patient-centered care. However, interactions and timing should take place only when the whole picture is taken into account.

Chemotherapy-Induced Nausea and Vomiting: Incidence and Management in Jordan

Cancer patients experience a considerable number of symptoms during the course of their disease. Of these symptoms, chemotherapy-induced nausea and vomiting (CINV) is one of the most reported and it increases the cancer burden on patients. This study aims to assess the current status of CINV among Jordanian cancer patients, with regard to its incidence and management. A descriptive cross-sectional survey design was used. The study sample was 185 cancer patients. The mean age of participants was 46.6 years ( SD = 15.5, range = 18-76) and were mainly female (56.8%). The incidence of nausea and vomiting was high at 71.4% and 57.3%, respectively. Most of the patients (89.7%) received a 5-HT₃ antagonist therapy combined with corticosteroids therapy (81.1%). This study demonstrated a high incidence rate of all types of CINV, which was undertreated. Antiemetic treatment could be improved by encouraging nurses to introduce the internationally agreed guidelines into their daily clinical practice.

Anticipatory and consummatory pleasure and displeasure in major depressive disorder: An experience sampling study

Pleasure and displeasure can be parsed into anticipatory and consummatory phases. However, research on pleasure and displeasure in major depressive disorder (MDD), a disorder characterized by anhedonia, has largely focused on deficits in the consummatory phase. Moreover, most studies in this area have been laboratory-based, raising the question of how component processes of pleasure and displeasure are experienced in the daily lives of depressed individuals. Using experience sampling, we compared anticipatory and consummatory pleasure and displeasure for daily activities reported by adults with MDD (n = 41) and healthy controls (n = 39). Participants carried electronic devices for one week and were randomly prompted eight times a day to answer questions about activities to which they most and least looked forward. Compared to healthy controls, MDD participants reported blunted levels of both anticipatory and consummatory pleasure and elevated levels of both anticipatory and consummatory displeasure for daily activities. Independent of MDD status, participants accurately predicted pleasure but overestimated displeasure. These results are the first to provide evidence that, across both anticipatory and consummatory phases, individuals with MDD experience blunted pleasure and elevated displeasure for daily activities. Our findings clarify the disturbances in pleasure and displeasure that characterize MDD and may inform treatment for this debilitating disorder. (PsycINFO Database Record

Behavioral Status Influences the Dependence of Odorant-Induced Change in Firing on Prestimulus Firing Rate

The firing rate of the mitral/tufted cells in the olfactory bulb is known to undergo significant trial-to-trial variability and is affected by anesthesia. Here we ask whether odorant-elicited changes in firing rate depend on the rate before application of the stimulus in the awake and anesthetized mouse. We find that prestimulus firing rate varies widely on a trial-to-trial basis and that the stimulus-induced change in firing rate decreases with increasing prestimulus firing rate. Interestingly, this prestimulus firing rate dependence was different when the behavioral task did not involve detecting the valence of the stimulus. Finally, when the animal was learning to associate the odor with reward, the prestimulus firing rate was smaller for false alarms compared with correct rejections, suggesting that intrinsic activity reflects the anticipatory status of the animal. Thus, in this sensory modality, changes in behavioral status alter the intrinsic prestimulus activity, leading to a change in the responsiveness of the second-order neurons. We speculate that this trial-to-trial variability in odorant responses reflects sampling of the massive parallel input by subsets of mitral cells.SIGNIFICANCE STATEMENT The olfactory bulb must deal with processing massive parallel input from ∼1200 distinct olfactory receptors. In contrast, the visual system receives input from a small number of photoreceptors and achieves recognition of complex stimuli by allocating processing for distinct spatial locations to different brain areas. Here we find that the change in firing rate elicited by the odorant in second-order mitral cells depends on the intrinsic activity leading to a change of magnitude in the responsiveness of these neurons relative to this prestimulus activity. Further, we find that prestimulus firing rate is influenced by behavioral status. This suggests that there is top-down modulation allowing downstream brain processing areas to perform dynamic readout of olfactory information.

Hunger neurons drive feeding through a sustained, positive reinforcement signal

The neural mechanisms underlying hunger are poorly understood. AgRP neurons are activated by energy deficit and promote voracious food consumption, suggesting these cells may supply the fundamental hunger drive that motivates feeding. However recent in vivo recording experiments revealed that AgRP neurons are inhibited within seconds by the sensory detection of food, raising the question of how these cells can promote feeding at all. Here we resolve this paradox by showing that brief optogenetic stimulation of AgRP neurons before food availability promotes intense appetitive and consummatory behaviors that persist for tens of minutes in the absence of continued AgRP neuron activation. We show that these sustained behavioral responses are mediated by a long-lasting potentiation of the rewarding properties of food and that AgRP neuron activity is positively reinforcing. These findings reveal that hunger neurons drive feeding by transmitting a positive valence signal that triggers a stable transition between behavioral states.

DOI:http://dx.doi.org/10.7554/eLife.18640.001

Making sense of the sensory regulation of hunger neurons

AgRP and POMC neurons are two key cell types that regulate feeding in response to hormones and nutrients. Recently, it was discovered that these neurons are also rapidly modulated by the mere sight and smell of food. This rapid sensory regulation "resets" the activity of AgRP and POMC neurons before a single bite of food has been consumed. This surprising and counterintuitive discovery challenges longstanding assumptions about the function and regulation of these cells. Here we review these recent findings and discuss their implications for our understanding of feeding behavior. We propose several alternative hypotheses for how these new observations might be integrated into a revised model of the feeding circuit, and also highlight some of the key questions that remain to be answered.

Aging and balance control in response to external perturbations: role of anticipatory and compensatory postural mechanisms

The ability to maintain balance deteriorates with increasing age. Anticipatory and compensatory postural adjustments (APAs and CPAs, respectively), both, are known to be affected in the elderly. We examined the effect of aging on the ability of older adults to utilize APAs and its effect on subsequent control of posture (CPAs). Ten elderly individuals were exposed to external predictable and unpredictable perturbations applied to the upper body in the sagittal plane. Body kinematics, electromyographic activity of 13 muscles, and ground reaction forces were analyzed during the anticipatory and compensatory phases of postural control. The elderly were capable of recognizing an upcoming predictable perturbation and activated muscles prior to it. However, the older adults used different muscle strategies and sequence of muscle recruitment than that reported in young adults. Additionally, when the perturbations were unpredictable, no APAs were seen which resulted in large CPAs and greater peak displacements of the center of pressure (COP) and center of mass (COM) following perturbations. As opposed to this, when the perturbations were predictable, APAs were seen in older adults resulting in significantly smaller CPAs. The presence and utilization of APAs in older adults also improved postural stability following the perturbation as seen by significantly smaller COP and COM peak displacements. Using APAs in older adults significantly reduces the need for large CPAs, resulting in greater postural stability following a perturbation. The results provide a foundation for investigating the role of training in improving the interplay between anticipatory and compensatory postural control in older adults.

Neural mechanisms of rapid sensitivity to syntactic anomaly

Recent psycholinguistic models hypothesize that anticipatory processing can speed the response to linguistic input during language comprehension by pre-activating representations necessary for word recognition. We investigated the neurocognitive mechanisms of anticipatory processing by recording event-related potentials (ERPs) to syntactically anomalous (The thief was caught byfor police) and well-formed (e.g., The thief was caught bythe police) sentences. One group of participants saw anomalies elicited by the same word in every instance (e.g., for; low-variability stimuli), providing high affordances for predictions about the word-form appearing in the critical position. A second group saw anomalies elicited by seven different prepositions (at, of, on, for, from, over, with; high-variability stimuli) across the study, creating a more difficult prediction task. Syntactic category anomalies enhanced the occipital-temporal N170 component of the ERP, indicating rapid sensitivity – within 200 ms of word-onset – to syntactic anomaly. For low-variability but not the high-variability stimuli, syntactic anomaly also enhanced the earlier occipital-temporal P1 component, around 130 ms after word-onset, indicating that affordances for prediction engendered earlier sensitivity to syntactic anomaly. Independent components analysis revealed three sources within the ERP signal whose functional dynamics were consistent with predictive processing and early responses to syntactic anomaly. Distributed neural source modeling (sLORETA) of these early active sources produced a candidate network for early responses to words during reading in the right posterior occipital, left occipital-temporal, and medial parietal cortex.