Postural control in bipolar disorder: increased sway area and decreased dynamical complexity

Psychomotor slowing in schizophrenia is associated with aberrant postural control

Motor abnormalities, including psychomotor slowing, are prevalent in a large proportion of individuals with schizophrenia. While postural control deficits have been observed in this population, the impact of motor abnormalities on postural stability remains unclear. This study aimed to objectively evaluate postural stability in patients with and without psychomotor slowing and healthy controls. Seventy-three schizophrenia patients with psychomotor slowing (PS; Salpêtrière Retardation Rating Scale (SRRS) ≥ 15), 25 schizophrenia patients without psychomotor slowing (non-PS; SRRS < 15), and 27 healthy controls (HC) performed four conditions on the Kistler force plate: eyes open (EO), eyes closed (EC), head reclined with eyes open (EOHR), and head reclined with eyes closed (ECHR). Larger sway areas and higher Root Mean Square (RMS) values indicate lower postural stability, while a lower Complexity Index (CI) reflects reduced adaptability, flexibility, and dynamic functioning of postural control. PS exhibited larger sway areas and higher RMS compared to the other groups. Both PS and non-PS showed reduced complexity in postural control compared to healthy controls, without differences between the two patient groups. Reduced postural stability and complexity were associated with greater expert-rated motor abnormalities, as well as more severe negative symptoms. Additionally, lower complexity was linked to reduced physical activity levels. These findings suggest that psychomotor slowing is associated with lower postural stability, potentially reflecting impaired cerebellar function. Furthermore, the loss of complexity in postural control highlights reduced flexibility, adaptability, and efficiency in the postural control network of individuals with schizophrenia.

Altered brain regional homogeneity, depressive symptoms, and cognitive impairments in medication-free female patients with current depressive episodes in bipolar disorder and major depressive disorder

BACKGROUND

Although symptoms of depressive episodes in patients with bipolar depressive episodes (BDE) and major depressive disorder (MDD) are similar, the treatment strategies for these disorders are completely different, suggesting that BDE and MDD have different neurobiological backgrounds. In this study, we examined the relationship between brain function and clinical symptoms, particularly cognitive function, in female individuals with bipolar disorder and MDD experiencing depressive episodes.

METHODS

Regional homogeneity (ReHo) was analyzed in 51 medication-free female patients with BDE, 63 medication-free female patients with MDD, and 45 female healthy controls (HCs). Depressive symptom severity was assessed using the 24-item Hamilton Depression Rating Scale (HAMD-24), and multidimensional cognitive function was evaluated using the MATRICS Consensus Cognition Battery. Partial correlation analysis was used to explore the links between the brain regions and clinical characteristics. A support vector machine (SVM) was used to assess the classification accuracy.

RESULTS

Compared with HCs, patients with BDE and MDD had decreased ReHo in the left lobule VI of the cerebellum and increased ReHo in the left precuneus. Patients with BDE also had reduced ReHo in the left lobules IV-V of the cerebellum and increased ReHo in the right putamen, unlike patients with MDD who had no significant differences in these regions. Patients with BDE exhibited more severe cognitive deficits in processing speed, attention, word learning, and overall cognitive function than those with MDD. In patients with BDE, a significant negative correlation was found between the right putamen and HAMD-24 scores. However, no significant association was observed between abnormal ReHo levels and cognitive function. The SVM effectively differentiated between patients with BDE, MDD, and HCs.

CONCLUSION

Cognitive impairment was more severe in female patients with BDE than in those with MDD. Changes in the ReHo values of the right putamen and left lobules IV-V may serve as unique neuroimaging markers for BDE. Alterations in the ReHo values of the left precuneus and left lobule VI could serve as common pathophysiological mechanisms for BDE and MDD in women and indicate depressive states.

3D-optical motion capturing examination of sensori- and psychomotor abnormalities in mental disorders: Progress and perspectives

Sensori-/psychomotor abnormalities refer to a wide range of disturbances in individual motor, affective and behavioral functions that are often observed in mental disorders. However, many of these studies have mainly used clinical rating scales, which can be potentially confounded by observer bias and are not able to detect subtle sensori-/psychomotor abnormalities. Yet, an innovative three-dimensional (3D) optical motion capturing technology (MoCap) can provide more objective and quantifiable data about movements and posture in psychiatric patients. To draw attention to recent rapid progress in the field, we performed a systematic review using PubMed, Medline, Embase, and Web of Science until May 01st 2024. We included 55 studies in the qualitative analysis and gait was the most examined movement. The identified studies suggested that sensori-/psychomotor abnormalities in neurodevelopmental, mood, schizophrenia spectrum and neurocognitive disorders are associated with alterations in spatiotemporal parameters (speed, step width, length and height; stance time, swing time, double limb support time, phases duration, adjusting sway, acceleration, etc.) during various movements such as walking, running, upper body, hand and head movements. Some studies highlighted the advantages of 3D optical MoCap systems over traditional rating scales and measurements such as actigraphy and ultrasound gait analyses. 3D optical MoCap systems are susceptible to detecting differences not only between patients with mental disorders and healthy persons but also among at-risk individuals exhibiting subtle sensori-/psychomotor abnormalities. Overall, 3D optical MoCap systems hold promise for objectively examining sensori-/psychomotor abnormalities, making them valuable tools for use in future clinical trials.

A Novel Unsupervised Machine Learning Approach to Assess Postural Dynamics in Euthymic Bipolar Disorder

Bipolar disorder (BD) is a mood disorder with different phases alternating between euthymia, manic or hypomanic episodes, and depressive episodes. While motor abnormalities are commonly seen during depressive or manic episodes, not much attention has been paid to postural abnormalities during periods of euthymia and their association with illness burden. We collected 24-hour posture data in 32 euthymic participants diagnosed with BD using a shirt-based wearable. We extracted a set of nine time-domain features, and performed unsupervised participant clustering. We investigated the association between posture variables and 12 clinical characteristics of illness burden. Based on their postural dynamics during the daytime, evening, or nighttime, participants clustered in three clusters. Higher illness burden was associated with lower postural variability, in particular during daytime. Participants who exhibited a mostly upright sitting/standing posture during the night with frequent nighttime postural transitions had the highest number of lifetime depressive episodes. Euthymic participants with BD exhibit postural abnormalities that are associated with illness burden, especially with the number of depressive episodes. Our results contribute to understanding the role of illness burden on posture changes and sleep consolidation in periods of euthymia.

Unlocking the Emotional World of Visual Media: An Overview of the Science, Research, and Impact of Understanding Emotion: Drawing Insights From Psychology, Engineering, and the Arts, This Article Provides a Comprehensive Overview of the Field of Emotion Analysis in Visual Media and Discusses the Latest Research, Systems, Challenges, Ethical Implications, and Potential Impact of Artificial Emotional Intelligence on Society

The emergence of artificial emotional intelligence technology is revolutionizing the fields of computers and robotics, allowing for a new level of communication and understanding of human behavior that was once thought impossible. While recent advancements in deep learning have transformed the field of computer vision, automated understanding of evoked or expressed emotions in visual media remains in its infancy. This foundering stems from the absence of a universally accepted definition of "emotion," coupled with the inherently subjective nature of emotions and their intricate nuances. In this article, we provide a comprehensive, multidisciplinary overview of the field of emotion analysis in visual media, drawing on insights from psychology, engineering, and the arts. We begin by exploring the psychological foundations of emotion and the computational principles that underpin the understanding of emotions from images and videos. We then review the latest research and systems within the field, accentuating the most promising approaches. We also discuss the current technological challenges and limitations of emotion analysis, underscoring the necessity for continued investigation and innovation. We contend that this represents a "Holy Grail" research problem in computing and delineate pivotal directions for future inquiry. Finally, we examine the ethical ramifications of emotion-understanding technologies and contemplate their potential societal impacts. Overall, this article endeavors to equip readers with a deeper understanding of the domain of emotion analysis in visual media and to inspire further research and development in this captivating and rapidly evolving field.

Functional connectivity of the cerebellar vermis in bipolar disorder and associations with mood

Purpose

Studies of the neural underpinnings of bipolar type I disorder have focused on the emotional control network. However, there is also growing evidence for cerebellar involvement, including abnormal structure, function, and metabolism. Here, we sought to assess functional connectivity of the cerebellar vermis with the cerebrum in bipolar disorder and to assess whether connectivity might depend on mood.

Methods

This cross-sectional study enrolled 128 participants with bipolar type I disorder and 83 control comparison participants who completed a 3 T magnetic resonance imaging (MRI) study, which included anatomical as well as resting state Blood Oxygenation Level Dependent (BOLD) imaging. Functional connectivity of the cerebellar vermis to all other brain regions was assessed. Based on quality control metrics of the fMRI data, 109 participants with bipolar disorder and 79 controls were included in the statistical analysis comparing connectivity of the vermis. In addition, the data was explored for the potential impacts of mood, symptom burden, and medication in those with bipolar disorder.

Results

Functional connectivity between the cerebellar vermis and the cerebrum was found to be aberrant in bipolar disorder. The connectivity of the vermis was found to be greater in bipolar disorder to regions involved in motor control and emotion (trending), while reduced connectivity was observed to a region associated with language production. In the participants with bipolar disorder, past depression symptom burden affected connectivity; however, no effects of medication were observed. Functional connectivity between the cerebellar vermis and all other regions revealed an inverse association with current mood ratings.

Conclusion

Together the findings may suggest that the cerebellum plays a compensatory role in bipolar disorder. The proximity of the cerebellar vermis to the skull may make this region a potential target for treatment with transcranial magnetic stimulation.

Functional Connectivity of the Cerebellar Vermis in Bipolar Disorder and Associations with Mood

Purpose

Studies of the neural underpinnings of bipolar type I disorder have focused on the emotional control network. However, there is also growing evidence for cerebellar involvement, including abnormal structure, function, and metabolism. Here, we sought to assess functional connectivity of the cerebellum with the cerebrum in bipolar disorder and to assess whether any effects might depend on mood.

Methods

This cross-sectional study enrolled 128 participants with bipolar type I disorder and 83 control comparison participants who completed a 3T MRI scan, which included anatomical imaging as well as resting state BOLD imaging. Functional connectivity of the cerebellar vermis to all other brain regions was assessed. Based on quality control metrics of the fMRI data, 109 participants with bipolar disorder and 79 controls were used to in the statistical analysis comparing connectivity of the vermis as well as associations with mood. Potential impacts of medications were also explored.

Results

Functional connectivity of the cerebellar vermis in bipolar disorder was found to differ significantly between brain regions known to be involved in the control of emotion, motor function, and language. While connections with emotion and motor control areas were significantly stronger in bipolar disorder, connection to a region associated language production was significantly weaker. In the participants with bipolar disorder, ratings of depression and mania were inversely associated with vermis functional connectivity. No effect of medications on these connections were observed.

Conclusion

Together the findings suggest cerebellum may play a compensatory role in bipolar disorder and when it can no longer fulfill this role, depression and mania develop. The proximity of the cerebellar vermis to the skull may make this region a potential target for treatment with transcranial magnetic stimulation.

Falls in community-dwelling women with bipolar disorder: a case-control study

BACKGROUND

Falls are a common occurrence in psychiatric hospital settings, however population-based research among individuals with psychiatric disorders, in particular bipolar disorder (BD) is scant. Thus, we aimed to investigate falls risk in community-dwelling women diagnosed with BD.

METHODS

Women with BD (cases, n = 119) were recruited from health care settings located in southeast Victoria, Australia. Age-matched controls (n = 357, ratio 3:1) without BD were participants in the Geelong Osteoporosis Study drawn from the same geographical region. Lifetime history of BD was identified by semi-structured clinical interview (SCID-IV/NP). Previous 12-month falls data were obtained via questionnaire. Information on mobility, alcohol use, general health, medication use, blood pressure, body mass index, socioeconomic status and use of a walking aid was collected. Generalised Estimating Equations, binary and ordinal logistic regression were used to determine the odds ratio (OR) and 95% confidence interval (CI) for falls following adjustment for confounders.

RESULTS

During the 12-month period, 34 (28.6%, median age 48.4 yr) cases and 70 (19.6%, median age 49.1 yr) controls reported one fall; 22 (18.5%) cases and 18 (5.0%) controls reported ≥ two falls (p < 0.001). Cases had 2.5-fold increased odds of at least one fall and 2.9-fold increased likelihood of increasing falls categories (0 vs. 1 vs. 2 +), compared to controls [adjOR 2.5, 95%CI (1.8, 3.4), adjOR OR 2.9, 95%CI (2.0, 4.1)].

CONCLUSION

Risk of falls was greater among women with BD. Balance training could be a research and clinical focus for falls prevention programs among women with bipolar disorder to prevent the detrimental outcomes associated with falling.

Effects of multitask training on cognition and motor control in people with schizophrenia spectrum disorders

Schizophrenia spectrum disorder (SSD) is a disabling mental illness that causes considerable deficits in motor and cognitive functions. The purpose of this study was to examine the effects of combining traditional multitask training (TMT) and video games--a new form of multitask training (video game multitask training VGMT)--on cognition and motor control performance in people with SSD. This was a quasi-experimental, pretest-posttest design study. A total of 25 patients participated in this study voluntarily (13 males and 12 females, average age = 59.61 years, SD– 11.46 years). All participants underwent two stages of training. The first stage involved TMT, and the second stage involved VGMT. Each training stage was 12 weeks long, with sessions twice a week that lasted for 40 minutes. Cognition, upper extremity motor and postural control performance, and functional mobility and subjective balance confidence were measured at three times: before and after the first-stage training and after the second-stage training. The results revealed that TMT and the combination of TMT and VGMT improved SSD patient’s cognition, upper extremity motor control, functional mobility and postural control performance. The subjective confidence of balance during the performance of daily activities was also mildly improved. Training with multitasks in the form of video games tended to further improve the outcome measures. Patients with SSD could benefit from regular participation in various forms of multitasking activities. Whether video games training are better than TMT in improving the functional ability of people with SSD needs further investigation.

Study protocol registration: Clinicaltrials.gov, ID: NCT04629898. Registered brief title: Level of Immersion of Virtual Reality and Cognition and Motor Performance in Patients of Schizophrenia Spectrum Disorder.

Superficial white-matter functional networks changes in bipolar disorder patients during depressive episodes

BACKGROUND

Bipolar disorder is a common psychiatric disorder characterized by insufficient or ineffective connections associated with white-matter (WM) abnormalities. Previous studies have detected the structural attributes of WM using magnetic resonance imaging (MRI) or diffusion tensor imaging, however, they failed to disentangle the dysfunctional organization within the WM.

METHODS

This study aimed to uncover the WM functional connectivity (FC) in 45 bipolar disorder patients during depressive episodes (BDD) and 45 healthy controls based on resting-state functional MRI. Eight WM functional networks were identified by using a clustering analysis of voxel-based correlation profiles, which were further classified into superficial, middle and deep layers of networks.

RESULTS

Group comparisons on the FCs among 8 WM networks showed that the superficial tempofrontal network (TFN) in BDD patients had increased FC with the superficial cerebellar network (CN) and with the superficial pre/post-central network (PCN). Further, support vector regression prediction analysis results revealed that the increased FCs of CN-TFN and PCN-TFN could be served as features to predict the numbers of depressive episode in BDD patients.

CONCLUSIONS

The current study extended our knowledge about the impaired WM functional connections associated with emotional and sensory-motor perception processing in BDD, which may facilitate the interpretation of the pathophysiology mechanisms underlying BDD.

Altered Complexity of Spontaneous Brain Activity in Schizophrenia and Bipolar Disorder Patients

BACKGROUND

Schizophrenia (SC) and bipolar disorder (BP) share elements of symptoms and the underlying neural mechanisms for both remain unclear. Recently, the complexity of spontaneous functional MRI (fMRI) signals in brain activity has been investigated in SC and BP using multiscale sample entropy (MSE) with inconsistent results.

PURPOSE

To perform MSE analysis across five time scales to assess differences in resting-state fMRI signal complexity in SC, BP, and normal controls (NC).

STUDY TYPE

Retrospective.

POPULATION

Fifty SC, 49 BP, and 49 NC.

FIELD STRENGTH/SEQUENCE

A 3 T, T2* weighted echo planar imaging (EPI) sequence.

ASSESSMENT

The mean MSEs of all gray matter (GM) and of 12 regions of interest (ROIs) were extracted using masks across the five scales. The regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF) in these ROIs were also determined and the relationship between the three measures was investigated. The correlations between cognitive assessment scores and MSE values were also explored.

STATISTICAL TESTS

Bonferroni correction, One-way ANOVA, Spearman rank correlation coefficient (r), Gaussian random field (GRF) correction.

RESULTS

There were decreased GM MSE values in the patient groups (F = 9.629, P < 0.05). SC and BP patients demonstrated lower complexity than NCs in the calcarine fissure, precuneus, inferior occipital gyrus, lingual gyrus and cerebellum, and higher complexity in the median cingulate, thalamus, hippocampus, middle temporal gyrus and middle frontal gyrus. There were significant differences between SC and BP patients in the precuneus (F = 4.890, P < 0.05) and inferior occipital gyrus (F = 5.820, P < 0.05). Calcarine fissure, cingulate, temporal gyrus, occipital gyrus, hippocampus, precuneus, frontal gyrus, and lingual gyrus MSE values were significantly correlated with both ReHo (r > 0.282, P < 0.05) and ALFF (r > 0.278, P < 0.05). Furthermore, median temporal MSE (r = -0.321, P < 0.05) on scale 3 and (r = -0.307, P < 0.05) on scale 4 and median cingulate MSE (r = -0.337, P < 0.05) on scale 5 was significantly negatively correlated with cognitive assessment scores.

DATA CONCLUSION

These data highlight different patterns of brain signal intensity complexity in SC and BP.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage 1.

Exploring the Relationship of Transdiagnostic Mood and Psychosis Symptom Domains with Motor Dysfunction

BACKGROUND

A number of motor abnormalities have been reported in psychotic disorders, including dyskinesia and psychomotor slowing. There is also evidence for many of the same motor abnormalities in biological first-degree relatives and accruing evidence for motor abnormalities in bipolar disorder. In addition to motor dysfunction, there are also shared symptom domains amongst these populations.

OBJECTIVES

We explored the associations of (1) current and lifetime psychosis and mood symptom domains and (2) domains of psychosis proneness with various domains of motor function in a transdiagnostic sample (n = 149).

METHOD

Individuals with schizophrenia, schizoaffective disorder, or bipolar disorder, biological first-degree relatives of individuals with a psychotic disorder, and controls completed measures of psychomotor speed and movement fluidity, and neural activity related to motor preparation (stimulus-locked lateralized readiness potential, S-LRP) and execution (response-locked LRP) was assessed using EEG. All participants completed the Brief Psychiatric Rating Scale; patients were additionally assessed for lifetime psychosis and mood episode symptoms, and relatives and controls completed the Chapman psychosis proneness scales.

RESULTS

Multiple regression revealed levels of current negative symptoms and mania were significantly positively associated with psychomotor slowing even after accounting for current antipsychotic medication dosage and duration of illness. S-LRP onset latency was significantly positively associated with magical ideation.

CONCLUSION

Domains of motor function are associated with various mood and psychosis symptom domains in a transdiagnostic sample, which may provide insight into brain abnormalities relevant to the expression of symptoms across disorders.

Gait, balance, mobility and muscle strength in people with anxiety compared to healthy individuals

BACKGROUND

Anxiety disorders are the most common mental disorders. Changes in psychomotor behavior can be observed in gross motor skills, with gait disturbances thought to reflect defective brain functions in psychiatric conditions. While balance deficits are well documented in anxiety, only little is known about gait characteristics of people with anxiety.

OBJECTIVE

This study wishes to examine the existence of differences in gait, balance, mobility and muscle strength between people with anxiety and healthy individuals, and to investigate the relationship between level of anxiety and motor characteristics.

METHODS

An observational study was conducted in a psychiatric out-patient unit at a large Israeli general hospital. The sample consisted of 93 participants, ages 18-65: 48 of them (27 female, 21 male) categorized as having anxiety, and 45 (25 female, 20 male) without anxiety. Participants were divided into two groups of various ages and both genders, and completed two questionnaires and four physical tests: objective anxiety assessment (Hamilton Anxiety Rating Scale); spatiotemporal gait parameters (10-meter walking test); balance function (Unipedal Stance Test); muscle strength evaluation, and mobility (Time Up and Go Test). No attempt was made to correlate between the anxiety and control groups based on age and/or gender.

RESULTS

Participants with anxiety (both genders) were characterized by slower walking speed, shorter step length, and fewer steps per minute (p < 0.001), as well as balance deficiency and mobility dysfunction (p < 0.001), compared to the control group. Muscle strength in women with anxiety was found to be significantly lower than in healthy women.

CONCLUSIONS

To the best of our knowledge, this study is the first of its kind to examine spatiotemporal gait components in patients with anxiety. Based on the findings, there is room to consider implementing gait analysis into the physical examination of patients with anxiety, as well as muscle strength, balance, and mobility function. Correct assessment and proper treatment of these aspects might contribute to the well-being of patients with anxiety.

Abnormal postural behavior in patients with functional movement disorders during exposure to stress

BACKGROUND

Patients affected by functional (psychogenic) movement disorders (FMD) have abnormal processing of stress responses. However, little is known about the influence of this abnormal stress processing on automatic motor defense behavior, such as freeze response. Our aim was thus to investigate stress-induced postural motor responses in FMD.

METHODS

Nine FMD patients and thirteen healthy controls were engaged in the Trier Social Stress Test, while we measured the movement of their body by means of accelerometers and gyroscopes attached to the thorax. Standard deviation of thorax acceleration, reflecting the variability of movement amplitude (body sway), was compared across groups over time in a 2 × 2 ANOVA design. Higuchi's fractal dimension (HFD), reflecting the complexity of movement pattern over time, was also analyzed. Salivary cortisol and α-amylase samples were collected before and after the experiment, as stress biomarkers. Pearson's correlation coefficients were calculated between these biomarkers and movement parameters.

RESULTS

A significant interaction effect was found, showing that healthy controls reduced their thorax sway over time during exposure to stress (from 0.027 ± 0.010 m/s² to 0.023 ± 0.008 m/s², effect size of Cohen's d = 0.95), whereas patients with FMD did not. This change in body sway in controls over time negatively correlated with salivary cortisol values (ρ = -0.67, p = 0.012). A significant group effect revealed that FMD patients had an overall larger body sway (0.038 ± 0.013 m/s²) compared to controls (0.025 ± 0.009 m/s² - effect size of Cohen's d = 1.29) and a lower HFD (1.602 ± 0.071) than controls (1.710 ± 0.078 - Cohen's d = 1.43).

CONCLUSIONS

Patients with FMD failed to show a reduction of body sway over time, i.e., freeze response observed in the controls, thus suggesting an impairment in the automatic defense behavior. Moreover, our analysis found a lower complexity of movement (HFD) in FMD, which deserves future research in order to verify whether this could represent a characteristic trait of the disorder.

The effect of mood phases on balance control in bipolar disorder

The aim of this study was to investigate balance control during gait and sit-to-walk in individuals with bipolar disorder and healthy controls by examining the inclination angles between the whole-body center-of-mass (COM) and ankle in the sagittal plane. Twenty-one individuals with bipolar disorder in the euthymic (i.e., asymptomatic; n = 11) and depressed (n = 10) phases and 7 healthy controls (ages between 18 and 45) performed gait and sit-to-walk at self-selected comfortable speed. Mood phases for individuals with bipolar disorder were measured using the Patient Health Questionnaire and Altman Self-Rating Mania Scale. We collected motion data using a 16-camera motion capture technology. We found smaller COM-ankle inclination angles at seat-off during sit-to-walk for the bipolar-depressed group compared to the bipolar-euthymic and healthy groups, indicating poorly controlled balance for the bipolar-depressed group in sit-to-walk. However, we found larger COM-ankle inclination angles at beginning of single stance phase of gait for the bipolar-euthymic group compared to the healthy group, indicating well controlled balance for the bipolar-euthymic group in gait. Our results suggest an association between the depressed phase and balance impairment during daily movements in relatively young adults (ages ≤ 45 years). Our results also suggest that the depressed phase may be as detrimental to balance control as the effect of age-related neuromuscular weakness.

Factors associated with self-reported falls, balance or walking difficulty in older survivors of breast, colorectal, lung, or prostate cancer: Results from Surveillance, Epidemiology, and End Results-Medicare Health Outcomes Survey linkage

Background

Cancer and its treatment affect body systems that are important in preventing falls and controlling balance/walking. This study examined factors associated with self-reported falls and balance/walking difficulty in the past 12 months in older survivors of four major cancers.

Methods

This was a cross-sectional study analyzing population-based data from Surveillance, Epidemiology, and End Results–Medicare Health Outcomes Survey (SEER-MHOS). Data from cohorts 9 to 14 (January 2006 to December 2013) were extracted. Inclusion criteria were: age ≥65 years at cancer diagnosis, first MHOS completed during years 1–5 post-cancer diagnosis, first primary breast (n = 2725), colorectal (n = 1646), lung (n = 752), and prostate (n = 4245) cancer, and availability of cancer staging information. Primary outcomes were self-reported falls and balance/walking difficulty in the past 12 months. Multivariable logistic regression was constructed for each cancer type to examine independent factors associated with falls and balance/walking difficulty.

Results

In all cancer types, advancing age at cancer diagnosis and dependence in activities of daily living were significant independent factors associated with increased odds of reporting falls and balance/walking difficulty in the past 12 months. Additionally, depression was independently associated with falls and sensory impairment in feet was independently linked to balance/walking difficulty in all cancer types. Other independent factors of falls and balance/walking difficulty varied across cancer types. In breast cancer only, localized or regional cancer stage was significantly associated with increased odds of reporting falls and balance/walking difficulty, whereas treatment with radiation decreased the odds of falling. No association between falls and balance/walking difficulty with time since cancer diagnosis, cancer stage, or cancer treatment was found in colorectal, lung, and prostate cancer.

Conclusion

There exists some heterogeneity in factors associated with self-reported falls and balance/walking difficulty between different cancer types. Future research is necessary to ascertain factors predictive of falls and balance/walking difficulty in older cancer survivors, particularly factors related to cancer diagnosis and treatment.

Motor behavior characteristics in various phases of bipolar disorder revealed through biomechanical analysis: Quantitative measures of activity and energy variables during gait and sit-to-walk

Abnormal motor behaviors influenced by high or low energy states are key signs and symptoms for mania/hypomania or depression, respectively. Clinical evaluation is currently based on qualitative, subjective self-reports. We aimed to objectively quantify activity and energy variables during gait and sit-to-walk in bipolar disorder. Gait and sit-to-walk were analyzed in 31 individuals with bipolar disorder (five hypomanic, 14 euthymic and 12 depressed) and 14 healthy controls using a motion capture system and two force platforms. The 9-item Patient Health Questionnaire and Altman Self Rating Mania Scale were administered to evaluate mood symptoms. During gait and sit-to-walk, the hypomanic group had 20-30% greater movement speed and produced 10-60% greater peak force, and 40-140% greater peak power in the knee or ankle compared to the euthymic, depressed and healthy groups. Biomechanical measures of activity and energy correlated with clinically defined hypomania. Our findings suggest that movement speed and force production could serve as objective activity and energy markers for hypomanic symptoms in individuals with bipolar disorder, but this study was based on a relatively small sample size, and the laboratory-based assessments are not directly transferable to a clinical setting.

Alterations of the cerebellum and basal ganglia in bipolar disorder mood states detected by quantitative T1ρ mapping

OBJECTIVES

Quantitative mapping of T1 relaxation in the rotating frame (T1ρ) is a magnetic resonance imaging technique sensitive to pH and other cellular and microstructural factors, and is a potentially valuable tool for identifying brain alterations in bipolar disorder. Recently, this technique identified differences in the cerebellum and cerebral white matter of euthymic patients vs healthy controls that were consistent with reduced pH in these regions, suggesting an underlying metabolic abnormality. The current study built upon this prior work to investigate brain T1ρ differences across euthymic, depressed, and manic mood states of bipolar disorder.

METHODS

Forty participants with bipolar I disorder and 29 healthy control participants matched for age and gender were enrolled. Participants with bipolar disorder were imaged in one or more mood states, yielding 27, 12, and 13 imaging sessions in euthymic, depressed, and manic mood states, respectively. Three-dimensional, whole-brain anatomical images and T1ρ maps were acquired for all participants, enabling voxel-wise evaluation of T1ρ differences between bipolar mood state and healthy control groups.

RESULTS

All three mood state groups had increased T1ρ relaxation times in the cerebellum compared to the healthy control group. Additionally, the depressed and manic groups had reduced T1ρ relaxation times in and around the basal ganglia compared to the control and euthymic groups.

CONCLUSIONS

The study implicated the cerebellum and basal ganglia in the pathophysiology of bipolar disorder and its mood states, the roles of which are relatively unexplored. These findings motivate further investigation of the underlying cause of the abnormalities, and the potential role of altered metabolic activity in these regions.

Impaired sensory processing measured by functional MRI in Bipolar disorder manic and depressed mood states

Bipolar disorder is characterized by recurring episodes of depression and mania. Defining differences in brain function during these states is an important goal of bipolar disorder research. However, few imaging studies have directly compared brain activity between bipolar mood states. Herein, we compare functional magnetic resonance imaging (fMRI) responses during a flashing checkerboard stimulus between bipolar participants across mood states (euthymia, depression, and mania) in order to identify functional differences between these states. 40 participants with bipolar I disorder and 33 healthy controls underwent fMRI during the presentation of the stimulus. A total of 23 euthymic-state, 16 manic-state, 15 depressed-state, and 32 healthy control imaging sessions were analyzed in order to compare functional activation during the stimulus between mood states and with healthy controls. A reduced response was identified in the visual cortex in both the depressed and manic groups compared to euthymic and healthy participants. Functional differences between bipolar mood states were also observed in the cerebellum, thalamus, striatum, and hippocampus. Functional differences between mood states occurred in several brain regions involved in visual and other sensory processing. These differences suggest that altered visual processing may be a feature of mood states in bipolar disorder. The key limitations of this study are modest mood-state group size and the limited temporal resolution of fMRI which prevents the segregation of primary visual activity from regulatory feedback mechanisms.

Posture-Motor and Posture-Ideomotor Dual-Tasking: A Putative Marker of Psychomotor Retardation and Depressive Rumination in Patients With Major Depressive Disorder

Background: Recent studies have demonstrated that the assessment of postural performance may be a potentially reliable and objective marker of the psychomotor retardation (PMR) in the major depressive disorder (MDD). One of the important facets of MDD-related PMR is reflected in disrupted central mechanisms of psychomotor control, heavily influenced by compelling maladaptive depressive rumination. In view of this we designed a research paradigm that included sequential execution of simple single-posture task followed by more challenging divided attention posture tasks, involving concurring motor and ideomotor workloads. Another difficulty dimension assumed executing of all the tasks with eyes open (EO) (easy) and closed (EC) (difficult) conditions. We aimed at investigating the interplay between the severity of MDD, depressive rumination, and efficiency of postural performance.

Methods: Compared with 24 age- and body mass index-matched healthy controls (HCs), 26 patients with MDD sequentially executed three experimental tasks: (1) single-posture task of maintaining a quiet stance (ST), (2) actual posture-motor dual task (AMT); and (3) mental/imaginary posture-motor dual task (MMT). All the tasks were performed in the EO and the EC conditions. The primary dependent variable was the amount of kinetic energy (E) expended for the center of pressure deviations (CoPDs), whereas the absolute divided attention cost index showed energy cost to the dual-tasking vs. the single-posture task according to the formula: ΔE = (E_Dual-task - E_Single-task).

Results: The signs of PMR in the MDD group were objectively indexed by deficient posture control in the EC condition along with overall slowness of fine motor and ideomotor activity. Another important and probably more challenging feature of the findings was that the posture deficit manifested in the ST condition was substantially and significantly attenuated in the MMT and AMT performance dual-tasking activity. A multiple linear regression analysis evidenced further that the dual-tasking energy cost (i.e., ΔE) significantly predicted clinical scores of severity of MDD and depressive rumination.

Conclusion: The findings allow to suggest that execution of concurrent actual or imaginary fine motor task with closed visual input deallocates attentional resources from compelling maladaptive depressive rumination thereby attenuating severity of absolute dual-tasking energy costs for balance maintenance in patients with MDD.

Significance: Quantitative assessment of PMR through measures of the postural performance in dual-tasking may be useful to capture the negative impact of past depressive episodes, optimize the personalized treatment selection, and improve the understanding of the pathophysiological mechanisms underlying MDD.

The clinical and prognostic value of motor abnormalities in psychosis, and the importance of instrumental assessment

Motor abnormalities comprise several clinical signs intrinsic to psychosis. Critically, these features are of prognostic value in individuals at-risk for psychosis, and for those in early stages of psychotic disorders. Motor abnormalities such as tremor, rigidity, and neurological soft signs often go unrecognized. Currently, advances in this area are limited by a paucity of theoretical conceptions categorizing or linking these behaviours to underlying neurobiology affected in psychosis. However, emerging technological advances have significantly improved the ability to detect and assess motor abnormalities with objective instruments in a timely and reliable manner. Further, converging evidence has laid the groundwork for theoretically and empirically derived categorization and conceptualization. This review summarizes these advances, stressing the importance of motor abnormalities for understanding vulnerability across different stages of psychosis and introducing these innovative instrumental approaches. Patients, researchers and clinicians will benefit from these new developments, as better assessment aids the development of targeted interventions to ultimately improve the care for individuals experiencing psychosis.

Posture-cognitive dual-tasking: A relevant marker of depression-related psychomotor retardation. An illustration of the positive impact of repetitive transcranial magnetic stimulation in patients with major depressive disorder

This study examined whether postural control variables, particularly the center-of-pressure (COP) velocity-based parameters, could be a relevant hallmark of depression-related psychomotor retardation (PMR). We first aimed at investigating the interplay between the PMR scores and the COP performance in patients with major depressive disorder (MDD), as compared to age-matched healthy controls; secondly, we focused on the impact of a repetitive transcranial magnetic stimulation (rTMS) treatment on depression, PMR scores and postural performance. 16 MDD patients, and a control group of 16 healthy adults, were asked to maintain quiet standing balance during two trials with or without vision, and while backward counting (dual task). All the position and velocity-based COP variables were computed. Before and after the rTMS session (n eligible MDD = 10), we assessed the depression level with the Montgomery-Asberg Depression Rating Scale (MADRS), the PMR scores with the French Retardation Rating Scale for Depression (ERD), and postural performance. Before the treatment, significant positive partial correlations were found between the pre-ERD scores and the velocity-based COP variables, especially in the dual-task conditions (p < 0.05). In contrast, there was no significant correlation between the post-ERD scores and any postural parameter after the treatment. The MADRS and ERD scores showed a significant decrease between before and after the rTMS intervention. For the first time, the findings clearly validated the view that the assessment of postural performance - easy to envisage in clinical settings-constitutes a reliable and objective marker of PMR in MDD patients.

Neurological and cerebellar soft signs do not discriminate schizophrenia from bipolar disorder patients

Patients with schizophrenia (SZ) and bipolar disorder (BD) share subtle motor abnormalities called the neurological soft signs (NSS). Since in both diseases there is evidence for alterations in cerebellar functions, structure and connectivity, we expected that the cerebellar soft signs (CSS), analogue of NSS focusing strictly on cerebellar symptoms, would be also a common trait in SZ and BD. We examined 30 patients with BD, 30 patients with SZ and 28 control subjects using the Neurological Evaluation Scale (NES, for NSS) and International Cooperative Ataxia Rating Scale (ICARS, for CSS). SZ and BD did not differ in total and subscales' scores in both NES and ICARS. Subscale analysis revealed that SZ performed significantly worse than controls in all the subscales of both NES and ICARS. BD patients scored significantly worse than controls in all NES subscales and in oculomotor and kinetic subscales of the ICARS, while other ICARS subscales did not differentiate those two groups. To our knowledge this is the first study to show that CSS constitute common symptoms in BD and SZ. We recommend a special focus on those diseases in further research regarding structural and functional changes of cerebellum and their clinical outcome.

Postural Sway and Clinical Characteristics in Patients with Psychotic Disorders: A Review

Postural instability is a feature that is frequently observed in patients with psychotic disorders. Previous studies applied rating scales or behavioral test to assess postural instabilities. Recently, a pressure-sensitive platform has been used to study detailed characteristics of postural sway and regulation. However, characteristics of posturography indices in patients with psychotic disorders have not been well documented. To integrate the findings from studies that assessed postural sway using posturography in patients with psychotic disorders, we conducted a systematic review. Following database literature search, we identified nine eligible articles. Assessment conditions and indices of postural stability varied between studies. Postural control was associated with negative and general psychopathology in two studies. Two studies reported associations between posturographic variables and medication dose, whereas four studies reported no associations. This review identified the need to develop standards to assess postural sway in patients with psychiatric disorders. Further studies need to report associations between postural sway and confounding factors.

Balance characteristics in patients with major depression after a two-month walking exercise program: A pilot study

Recent studies have demonstrated impaired balance performance in patients with major depressive disorder (MDD) in comparison to healthy controls (HC), which is likely to be related to deficits in integration of visual and proprioceptive inputs necessary for efficient postural control. In parallel, considerable literature supports the positive effects of a walking program on depressive symptoms. Thus this study aimed to determine the effects of a two-month walking program on implicit postural control strategies in MDD. Compared with twelve age- and body mass index-matched non-psychiatric HC (mean age 50.41 ± 6.93 years; five women), nine MDD (mean age 51.88 ± 10.01 years; five women) performed two sessions of standing postural control assessment, separated by eight weeks of the walking program, while the HC were only assessed at t0. The walking program included one-hour supervised walking sessions, three times a week over a two-month period. Postural performance was assessed by various center of pressure (COP) parameters, in particular those that bound the COP velocity of postural sway. The primary findings were that MDD patients exhibited positive physical activity-related changes in postural performance, with a decrease in body sway in the most difficult condition (with a foam surface). The real impact of the walking program on COP velocity-based variables suggests that MDD patients improved their ability to make more efficient postural corrections, which is useful for daily activities and autonomy. A balance assessment in the clinical screening routine might be used as a new index of the effectiveness of walking programs recommended for people with depression.

TRIAL REGISTRATION

This study is registered at http://clinicaltrials.gov/: NCT01995422.

Updating the research domain criteria: the utility of a motor dimension

Within the NIMH Research Domain Criteria (RDoC) framework, dimensions of behavior are investigated across diagnoses with the goal of developing a better understanding of their underlying neural substrates. Currently, this framework includes five domains: cognitive, social, arousal/regulatory, negative, and positive valence systems. We argue that the inclusion of a motor systems domain is sorely needed as well. Independent of medication, distinct areas of motor dysfunction (e.g. motor planning/inhibition/learning/coordination, involuntary movements) commonly appear across a number of mental disorders (e.g. schizophrenia, bipolar disorder, autism, attention deficit hyperactivity disorder, Alzheimer's disease, depression) as well as neurological disorders accompanied by significant psychological symptoms (e.g. Parkinson's disease). In addition, motor systems are amenable to study across multiple levels of analysis from the cellular molecular level focusing on cytoarchitechtonics and neurotransmitter systems, to networks and circuits measured using neuroimaging, and finally at the level of overt behavioral performance. Critically, the neural systems associated with motor performance have been relatively well defined, and different circuits have been linked to distinct aspects of motor behavior. As such, they may also be differentially associated with symptoms and motor dysfunction across diagnoses, and be uniquely informative about underlying etiology. Importantly, motor signs can change across stages of illness; they are also often present in the prodromal phases of disease and closely linked with course, suggesting that these behaviors represent a core feature reflective of pathogenic processes. The inclusion of a motor domain would allow researchers to better understand psychopathology more broadly, and may also reveal important contributions to disease processes across diagnoses.

Brain abnormalities in bipolar disorder detected by quantitative T1ρ mapping

Abnormal metabolism has been reported in bipolar disorder, however, these studies have been limited to specific regions of the brain. To investigate whole-brain changes potentially associated with these processes, we applied a magnetic resonance imaging technique novel to psychiatric research, quantitative mapping of T1 relaxation in the rotating frame (T1ρ). This method is sensitive to proton chemical exchange, which is affected by pH, metabolite concentrations and cellular density with high spatial resolution relative to alternative techniques such as magnetic resonance spectroscopy and positron emission tomography. Study participants included 15 patients with bipolar I disorder in the euthymic state and 25 normal controls balanced for age and gender. T1ρ maps were generated and compared between the bipolar and control groups using voxel-wise and regional analyses. T1ρ values were found to be elevated in the cerebral white matter and cerebellum in the bipolar group. However, volumes of these areas were normal as measured by high-resolution T1- and T2-weighted magnetic resonance imaging. Interestingly, the cerebellar T1ρ abnormalities were normalized in participants receiving lithium treatment. These findings are consistent with metabolic or microstructural abnormalities in bipolar disorder and draw attention to roles of the cerebral white matter and cerebellum. This study highlights the potential utility of high-resolution T1ρ mapping in psychiatric research.

Randomized controlled trial of yoga for chronic poststroke hemiparesis: motor function, mental health, and quality of life outcomes

PURPOSE

To assess the efficacy of yoga for motor function, mental health, and quality of life outcomes in persons with chronic poststroke hemiparesis.

METHOD

Twenty-two individuals participated in a randomized controlled trial involving assessment of task-orientated function, balance, mobility, depression, anxiety, and quality of life domains before and after either a 10-week yoga intervention (n = 11) or no treatment (n = 11).

RESULTS

The yoga intervention did not result in any significant improvements in objective motor function measures, however there was a significant improvement in quality of life associated with perceived motor function (P = .0001) and improvements in perceived recovery approached significance (P = .072). Memory-related quality of life scores significantly improved after yoga intervention (P = .022), and those participating in the intervention exhibited clinically relevant decreases in state and trait anxiety.

CONCLUSIONS

Preliminary results offer promise for yoga as an intervention to address mental health and quality of life in persons with stroke-related activity limitations. There is a need to more rigorously evaluate these yoga benefits with a larger randomized controlled trial, which, based on this preliminary trial, is feasible.

Increased timing variability in schizophrenia and bipolar disorder

Theoretical and empirical evidence suggests that impaired time perception and the neural circuitry underlying internal timing mechanisms may contribute to severe psychiatric disorders, including psychotic and mood disorders. The degree to which alterations in temporal perceptions reflect deficits that exist across psychosis-related phenotypes and the extent to which mood symptoms contribute to these deficits is currently unknown. In addition, compared to schizophrenia, where timing deficits have been more extensively investigated, sub-second timing has been studied relatively infrequently in bipolar disorder. The present study compared sub-second duration estimates of schizophrenia (SZ), schizoaffective disorder (SA), non-psychotic bipolar disorder (BDNP), bipolar disorder with psychotic features (BDP), and healthy non-psychiatric controls (HC) on a well-established time perception task using sub-second durations. Participants included 66 SZ, 37 BDNP, 34 BDP, 31 SA, and 73 HC who participated in a temporal bisection task that required temporal judgements about auditory durations ranging from 300 to 600 milliseconds. Timing variability was significantly higher in SZ, BDP, and BDNP groups compared to healthy controls. The bisection point did not differ across groups. These findings suggest that both psychotic and mood symptoms may be associated with disruptions in internal timing mechanisms. Yet unexpected findings emerged. Specifically, the BDNP group had significantly increased variability compared to controls, but the SA group did not. In addition, these deficits appeared to exist independent of current symptom status. The absence of between group differences in bisection point suggests that increased variability in the SZ and bipolar disorder groups are due to alterations in perceptual timing in the sub-second range, possibly mediated by the cerebellum, rather than cognitive deficits.

Precursors of post-bout motion sickness in adolescent female boxers

Athletic head trauma (both concussive and sub-concussive) is common among adolescents. Head trauma often is followed by motion sickness-like symptoms, by changes in cognitive performance, and by changes in standing body sway. We evaluated adolescent female boxers who did and did not report motion sickness after a bout (i.e., a boxing match), together with a control group of non-boxers. We asked whether pre-bout body sway would differ between boxers who experienced post-bout motion sickness and those who did not. In addition, we asked whether pre-bout cognitive performance would differ between non-boxers and boxers with and without post-bout motion sickness. Seven of twenty boxers reported motion sickness after a bout. Pre-bout measures of cognitive performance and body sway were different in boxers who reported post-bout motion sickness than in boxers without post-bout sickness or controls. The results suggest that susceptibility to motion sickness-like symptoms in adolescent female boxers may be manifested in characteristic patterns of body sway and cognitive performance. It may be possible to use pre-bout data to predict susceptibility to post-bout symptoms.

Cerebellar networks in individuals at ultra high-risk of psychosis: impact on postural sway and symptom severity

Despite known deficits in postural control in patients with schizophrenia, this domain has not been investigated in youth at ultra high-risk (UHR) for psychosis. This is particularly relevant as postural control implicates dysfunction in the cerebellum-a region implicated in cognitive dysmetria conceptions of schizophrenia but poorly understood in the prodrome. Here, we extended our understanding of movement abnormalities in UHR individuals to include postural control, and have linked these deficits to both symptom severity and cerebello-cortical network connectivity. UHR and healthy control participants completed an instrumentally based balance task to quantify postural control along with a resting state brain imaging scan to investigate cerebellar networks. We also quantified positive and negative symptom severity with structured clinical interviews. The UHR group showed overall increased postural sway and decreased cerebello-cortical resting state connectivity, relative to controls. The decreased cerebello-cortical connectivity was seen across multiple networks. Postural sway was also correlated with cerebellar connectivity in this population and uniquely positively correlated with the severity of negative symptoms. Finally, symptom severity was also associated with cerebellar connectivity. Together, our results point to a potential deficit in sensory integration as an underlying contributor to the increased postural sway, and provide evidence of cerebellar abnormalities in UHR individuals. These results extend our understanding of the motor abnormalities of UHR individuals beyond striatum-based dyskinesias to include postural control and sensory integration deficits, and implicate the cerebellum as a distinct neural substrate preceding the onset of psychosis. Taken together, our results extend the cognitive dysmetria framework to UHR populations.

Characterization of information-based learning benefits with submovement dynamics and muscular rhythmicity

For skill advancement, motor variability must be optimized based on target information during practice sessions. This study investigated structural changes in kinematic variability by characterizing submovement dynamics and muscular oscillations after practice with visuomotor tracking under different target conditions. Thirty-six participants were randomly assigned to one of three groups (simple, complex, and random). Each group practiced tracking visual targets with trajectories of varying complexity. The velocity trajectory of tracking was decomposed into 1) a primary contraction spectrally identical to the target rate and 2) an intermittent submovement profile. The learning benefits and submovement dynamics were conditional upon experimental manipulation of the target information. Only the simple and complex groups improved their skills with practice. The size of the submovements was most greatly reduced by practice with the least target information (simple > complex > random). Submovement complexity changed in parallel with learning benefits, with the most remarkable increase in practice under a moderate amount of target information (complex > simple > random). In the simple and complex protocols, skill improvements were associated with a significant decline in alpha (8–12 Hz) muscular oscillation but a potentiation of gamma (35–50 Hz) muscular oscillation. However, the random group showed no significant change in tracking skill or submovement dynamics, except that alpha muscular oscillation was reduced. In conclusion, submovement and gamma muscular oscillation are biological markers of learning benefits. Effective learning with an appropriate amount of target information reduces the size of submovements. In accordance with the challenge point hypothesis, changes in submovement complexity in response to target information had an inverted-U function, pertaining to an abundant trajectory-tuning strategy with target exactness.

Acupuncture for management of balance impairment in a patient with bipolar disorder

A case is reported of unexplained unilateral thigh muscle atrophy and frequent falling with poor response to conventional conservative treatments in a patient with bipolar disorder who self-selected acupuncture treatment as a last resort. The patient experienced gradual improvements in lower extremity weakness and fewer falls during the 8-month treatment. No adverse event or aggravation of the bipolar disorder was observed. These outcomes suggest that acupuncture may be a feasible adjunct for reducing falling and restoring postural balances in patients with bipolar disorder.

Neural processing of emotional facial and semantic expressions in euthymic bipolar disorder (BD) and its association with theory of mind (ToM)

BACKGROUND

Adults with bipolar disorder (BD) have cognitive impairments that affect face processing and social cognition. However, it remains unknown whether these deficits in euthymic BD have impaired brain markers of emotional processing.

METHODOLOGY/PRINCIPAL FINDINGS

We recruited twenty six participants, 13 controls subjects with an equal number of euthymic BD participants. We used an event-related potential (ERP) assessment of a dual valence task (DVT), in which faces (angry and happy), words (pleasant and unpleasant), and face-word simultaneous combinations are presented to test the effects of the stimulus type (face vs word) and valence (positive vs. negative). All participants received clinical, neuropsychological and social cognition evaluations. ERP analysis revealed that both groups showed N170 modulation of stimulus type effects (face > word). BD patients exhibited reduced and enhanced N170 to facial and semantic valence, respectively. The neural source estimation of N170 was a posterior section of the fusiform gyrus (FG), including the face fusiform area (FFA). Neural generators of N170 for faces (FG and FFA) were reduced in BD. In these patients, N170 modulation was associated with social cognition (theory of mind).

CONCLUSIONS/SIGNIFICANCE

This is the first report of euthymic BD exhibiting abnormal N170 emotional discrimination associated with theory of mind impairments.

Motor deficits in schizophrenia quantified by nonlinear analysis of postural sway

Motor dysfunction is a consistently reported but understudied aspect of schizophrenia. Postural sway area was examined in individuals with schizophrenia under four conditions with different amounts of visual and proprioceptive feedback: eyes open or closed and feet together or shoulder width apart. The nonlinear complexity of postural sway was assessed by detrended fluctuation analysis (DFA). The schizophrenia group (n = 27) exhibited greater sway area compared to controls (n = 37). Participants with schizophrenia showed increased sway area following the removal of visual input, while this pattern was absent in controls. Examination of DFA revealed decreased complexity of postural sway and abnormal changes in complexity upon removal of visual input in individuals with schizophrenia. Additionally, less complex postural sway was associated with increased symptom severity in participants with schizophrenia. Given the critical involvement of the cerebellum and related circuits in postural stability and sensorimotor integration, these results are consistent with growing evidence of motor, cerebellar, and sensory integration dysfunction in the disorder, and with theoretical models that implicate cerebellar deficits and more general disconnection of function in schizophrenia.

Psychotropic-Related Hip Fractures: Meta-Analysis of First-Generation and Second-Generation Antidepressant and Antipsychotic Drugs

BACKGROUND:

In 2007, more than 18,000 adults aged 65 or older died from injuries related to falls, with up to 30% experiencing severe injuries such as hip fracture or head trauma. The economic impact of falls and fractures among older people is substantial, with direct economic consequences totaling $19 billion in 2000.

OBJECTIVE:

To evaluate the association between antipsychotic and antidepressant agents and the risk of hip fracture in older adults, across multiple studies.

METHODS:

An English-language PubMed/MEDLINE search for studies from January 1966 to January 2011 was conducted, using key words including aged, hip fracture, fractures, antidepressive agents, and antipsychotic agents, as well as individual drug names. Criteria for study inclusion were mean subject age greater than or equal to 65 years, adjusted for age and sex, hip fracture-specific results provided, data specific to a drug class, subclass, or single agents, and cohort or case-controlled study design. Two authors reviewed all studies for inclusion/exclusion. A random effects model was used to calculate summary odds ratios.

RESULTS:

A total of 166 studies were identified in the initial search. Ten antipsychotic-related and 14 antidepressant-related studies, representing more than 70,000 hip fracture cases and approximately 270,000 subjects from 4 continents, met the inclusion criteria. Summary odds ratios (95% CI) were first-generation (conventional) antipsychotics 1.68 (1.43 to 1.99), second-generation (atypical) antipsychotics 1.30 (1.14 to 1.49), first-generation (tricyclic) antidepressants 1.71 (1.43 to 2.04), and second-generation (selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and unique agents such as bupropion, mirtazapine, and trazodone) antidepressants 1.94 (1.37 to 2.76). Clear evidence of heterogeneity was noted among all antidepressant study analyses (I2 > 87%; Q statistic p < 0.05).

CONCLUSIONS:

All drug classes studied—first- and second-generation antipsychotics and antidepressants—were associated with an increased risk of hip fracture in predominantly older adult populations.