Correlates of real-world goal-directed behavior in schizophrenia.

BACKGROUND: Deficits in goal-directed behavior (i.e. behavior conducted to achieve a specific goal or outcome) are core to schizophrenia, difficult to treat, and associated with poor functional outcomes. Factors such as negative symptoms, effort-cost decision-making, cognition, and functional skills have all been associated with goal-directed behavior in schizophrenia as indexed by clinical interviews or laboratory-based tasks. However, little work has examined whether these factors relate to the real-world pursuit of goal-directed activities in this population. METHODS: This study aimed to fill this gap by using Ecological Momentary Assessment (four survey prompts per day for 1 week) to test hypotheses about symptom, effort allocation, cognitive, and functional measures associated with planned and completed goal-directed behavior in the daily lives of 63 individuals with schizophrenia. RESULTS: Individuals with schizophrenia completed more goal-directed activities than they planned [t(62) = -4.01, p < 0.001]. Motivation and pleasure (i.e. experiential) negative symptoms, controlling for depressive symptoms, negatively related to planned goal-directed behavior [odds ratio (OR) 0.92, p = 0.005]. Increased effort expenditure for high probability rewards (planned: OR 1.01, p = 0.034, completed: OR 1.01, p = 0.034) along with performance on a daily functional skills task (planned: OR 1.04, p = 0.002, completed: OR 1.03, p = 0.047) negatively related to both planned and completed goal-directed activity. CONCLUSIONS: Our results present correlates of real-world goal-directed behavior that largely align with impaired ability to make future estimations in schizophrenia. This insight could help identify targeted treatments for the elusive motivated behavior deficits in this population.

Asymmetric Hearing Loss in Adult Cochlear Implant Recipients: Results and Recommendations From a Multisite Prospective Clinical Trial.

OBJECTIVE: A multisite clinical trial was conducted to obtain cochlear implant (CI) efficacy data in adults with asymmetric hearing loss (AHL) and establish an evidence-based framework for clinical decision-making regarding CI candidacy, counseling, and assessment tools. Study hypotheses were threefold: (1) 6-month postimplant performance in the poor ear (PE) with a CI will be significantly better than preimplant performance with a hearing aid (HA), (2) 6-month postimplant performance with a CI and HA (bimodal) will be significantly better than preimplant performance with bilateral HAs (Bil HAs), and (3) 6-month postimplant bimodal performance will be significantly better than aided, better ear (BE) performance. DESIGN: Forty adults with AHL from four, metropolitan CI centers participated. Hearing criteria for the ear to be implanted included (1) pure-tone average (PTA, 0.5, 1, 2 kHz) of >70 dB HL, (2) aided, monosyllabic word score of ≤30%, (3) duration of severe-to-profound hearing loss of ≥6 months, and (4) onset of hearing loss ≥6 years of age. Hearing criteria for the BE included (1) PTA (0.5, 1, 2, 4 kHz) of 40 to 70 dB HL, (2) currently using a HA, (3) aided, word score of >40%, and (4) stable hearing for the previous 1-year period. Speech perception and localization measures, in quiet and in noise, were administered preimplant and at 3-, 6-, 9-, and 12-months postimplant. Preimplant testing was performed in three listening conditions, PE HA, BE HA, and Bil HAs. Postimplant testing was performed in three conditions, CI, BE HA, and bimodal. Outcome factors included age at implantation and length of deafness (LOD) in the PE. RESULTS: A hierarchical nonlinear analysis predicted significant improvement in the PE by 3 months postimplant versus preimplant for audibility and speech perception with a plateau in performance at approximately 6 months. The model predicted significant improvement in postimplant, bimodal outcomes versus preimplant outcomes (Bil HAs) for all speech perception measures by 3 months. Both age and LOD were predicted to moderate some CI and bimodal outcomes. In contrast with speech perception, localization in quiet and noise was not predicted to improve by 6 months when comparing Bil HAs (preimplant) to bimodal (postimplant) outcomes. However, when participants' preimplant everyday listening condition (BE HA or Bil HAs) was compared with bimodal performance, the model predicted significant improvement by 3 months for localization in quiet and noise. Lastly, BE HA results were stable over time; a generalized linear model analysis revealed bimodal performance was significantly better than performance with a BE HA at all postimplant intervals for most speech perception measures and localization. CONCLUSIONS: Results revealed significant CI and bimodal benefit for AHL participants by 3-months postimplant, with a plateau in CI and bimodal performance at approximately 6-months postimplant. Results can be used to inform AHL CI candidates and to monitor postimplant performance. On the basis of this and other AHL research, clinicians should consider a CI for individuals with AHL if the PE has a PTA (0.5, 1, 2 kHz) >70 dB HL and a Consonant-Vowel Nucleus-Consonant word score ≤40%. LOD >10 years should not be a contraindication.

Belief, Confidence, and Motivation to Use the Paretic Upper Limb in Daily Life Over the First 24 Weeks After Stroke.

BACKGROUND AND PURPOSE: The recovery patterns of upper limb (UL) impairment after stroke are established. Psychosocial factors such as belief that paretic UL recovery is possible, confidence, and motivation to use the paretic UL in everyday tasks are unexplored early after stroke. The purpose of this exploratory study was to characterize belief, confidence, and motivation to use the paretic UL in daily life, and self-perceived barriers to UL recovery over the first 24 weeks after stroke. METHODS: This was a longitudinal cohort study (N = 30) with 8 assessment sessions over the first 24 weeks after stroke. Belief, confidence, and motivation to use the paretic UL and self-perceived barriers were quantified via survey and analyzed using descriptive statistics. Change in the number of self-perceived barriers between weeks 2 and 24 was tested using a paired-samples t test. The relationship between UL capacity, depressive symptomatology, cognition, and each psychosocial factor was examined using Spearman rank-order correlation analyses. RESULTS: Twenty-two participants completed all study assessments. Belief, confidence, and motivation were high across the 24 weeks, with little variation. There was no difference between the average number of barriers from weeks 2 to 24. There was no relationship between the clinical measures and psychosocial factors at week 2, 12, or 24. DISCUSSION AND CONCLUSIONS: High levels of belief, confidence, and motivation appear consistent over the first 6 months after stroke. The lack of correlations between psychosocial factors and clinical measures suggests belief, confidence, and motivation may not be vulnerable to functional status early after stroke.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1 available at: http://links.lww.com/JNPT/A283).

Dose response of task-specific upper limb training in people at least 6 months poststroke: A phase II, single-blind, randomized, controlled trial.

OBJECTIVE: The objectives of this work were to (1) determine whether higher doses of motor therapy in chronic poststroke hemiparesis result in better outcomes, compared to lower doses, and (2) evaluate potential modifiers of the dose-response relationship. METHODS: Eighty-five adults with upper extremity paresis ≥6 months poststroke were randomized to one of four dose groups in this single-blind, parallel, randomized, control trial. The dosing parameter manipulated was amount of task-specific training, as indexed by the number of task repetitions. Groups received 3,200, 6,400, 9,600, or individualized maximum (IM) repetitions, during 1-hour sessions, 4 days/week for 8 weeks. The intervention was an individualized, progressive, task-specific upper-limb training program designed to improve upper-limb functional motor capacity. The primary outcome was the slope of the Action Research Arm Test (ARAT) during the intervention. Effects of dose and potential modifiers of the dose-response relationship were evaluated with hierarchical linear models. RESULTS: ARAT scores for the 3,200, 9,600, and IM groups improved over time as indicated by slopes (ΔARAT/week, mean ± standard errors) of 0.40 ± 0.15, 0.31 ± 0.16, and 0.66 ± 0.14, respectively (p < 0.05). The slope of the 6,400 group was smaller (-0.05 ± 0.15) and significantly different from the 3,200 and IM groups (p < 0.001). Initial motor capacity, neglect, and other tested characteristics did not modify the dose-response relationship. INTERPRETATION: Overall, treatment effects were small. There was no evidence of a dose-response effect of task-specific training on functional capacity in people with long-standing upper-limb paresis poststroke. Ann Neurol 2016;80:342-354.

Dissociated functional connectivity profiles for motor and attention deficits in acute right-hemisphere stroke.

Strokes often cause multiple behavioural deficits that are correlated at the population level. Here, we show that motor and attention deficits are selectively associated with abnormal patterns of resting state functional connectivity in the dorsal attention and motor networks. We measured attention and motor deficits in 44 right hemisphere-damaged patients with a first-time stroke at 1-2 weeks post-onset. The motor battery included tests that evaluated deficits in both upper and lower extremities. The attention battery assessed both spatial and non-spatial attention deficits. Summary measures for motor and attention deficits were identified through principal component analyses on the raw behavioural scores. Functional connectivity in structurally normal cortex was estimated based on the temporal correlation of blood oxygenation level-dependent signals measured at rest with functional magnetic resonance imaging. Any correlation between motor and attention deficits and between functional connectivity in the dorsal attention network and motor networks that might spuriously affect the relationship between each deficit and functional connectivity was statistically removed. We report a double dissociation between abnormal functional connectivity patterns and attention and motor deficits, respectively. Attention deficits were significantly more correlated with abnormal interhemispheric functional connectivity within the dorsal attention network than motor networks, while motor deficits were significantly more correlated with abnormal interhemispheric functional connectivity patterns within the motor networks than dorsal attention network. These findings indicate that functional connectivity patterns in structurally normal cortex following a stroke link abnormal physiology in brain networks to the corresponding behavioural deficits.

Personality pathology and increased use of medical resources in later adulthood.

OBJECTIVES: Personality pathology is associated with many negative health outcomes in young adulthood, including overutilization of healthcare resources. It is unclear, however, what the relation between personality pathology and medical resource utilization is as individuals age and develop new physical health problems. DESIGN: The present study examined whether personality disorder (PD) features were related to greater medical resource utilization in a sample of 1,630 community-dwelling participants, aged 55-64 years. PD features and health status were measured at baseline; medical resource utilization and new physical health problems were measured at four 6-month follow-up assessments. Multilevel modeling analyses tested associations between number of physical health problems and PD features in medical resource use over time. RESULTS: Greater number of physical health problems significantly predicted higher medical resource utilization. The results also showed that many PD features were related to higher reported medical resource utilization independent of health status and sociodemographic variables. Schizoid and schizotypal PD features were associated with less reported medical resource utilization. When all PDs were included in the model together, dependent, antisocial, histrionic, and narcissistic PD features remained predictive of higher medical resource utilization. CONCLUSIONS: Personality pathology remains a relevant predictor of greater medical resource utilization into later adulthood and should be considered an important risk factor when trying to determine ways to reduce costly overuse of healthcare resources among older adults.

Do emotion regulation difficulties in depression extend to social context? Everyday interpersonal emotion regulation in current and remitted major depressive disorder.

Individuals with major depressive disorder (MDD) have difficulties regulating emotion on their own. As people also use social resources to regulate emotion (i.e., interpersonal emotion regulation [IER]), we examined whether these difficulties extend to IER in current and remitted MDD compared to those with no psychiatric disorders (i.e., controls). Adults with current MDD (n = 48), remitted MDD (n = 80), and controls (n = 87) assessed via diagnostic interviewing completed 2-week experience sampling, reporting on how frequently (IER frequency), from whom (sharing partners), and why (IER goals) they sought IER; how the sharing partners responded (sharing partner's extrinsic IER strategies and warmth); and how their feelings about the problem and the sharing partner changed following IER (IER outcomes). Using multilevel modeling, the current-MDD group did not differ from controls in IER frequency and sharing partners, but the current-MDD group demonstrated a more mixed (albeit generally adaptive) profile of received IER strategies and benefited similarly or more from certain IER strategies than the other two groups, suggesting that IER may be a promising avenue for effective emotion regulation in current MDD. The remitted-MDD group sought IER most frequently and demonstrated the most adaptive profile of received IER strategies, and they and the current-MDD group reported seeking more types of IER goals than controls. People with remitted MDD seem highly motivated to pursue IER support and their pursuit takes place in particularly supportive social contexts. Research is needed to examine mechanisms driving these group differences and how IER predicts the course of MDD. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Age-related differences in delay discounting: Income matters.

Although the authors of a recent meta-analysis concluded there were no age-related differences in the discounting of delayed rewards, they did not examine the effects of income (Seaman et al., 2022). Accordingly, the present study compared discounting by younger and older adults (Ages 35-50 and 65-80) differing in household income. Two procedures were used: the Monetary Choice Questionnaire and the Adjusting-Amount procedure. Whereas no age difference was observed between the higher income (> $80,000) age groups, a significant difference was observed between younger and older adults with lower incomes (< $50,000): The younger adults discounted more steeply than the older adults. These findings, which were observed with both discounting procedures, support our buffering hypothesis, which assumes that the scarcity associated with a lower income is a stressor that can lead to steeper discounting, but that age-related increases in emotional stability can buffer such stressors, leading to age-related differences between lower income age groups. In contrast, no age difference was observed in higher income adults who experience much less scarcity. Further support for the buffering hypothesis comes from the finding that there was no age-related difference in discounting by the lower income groups when distress was statistically controlled. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Weight-bearing versus nonweight-bearing exercise for persons with diabetes and peripheral neuropathy: a randomized controlled trial.

OBJECTIVE: To determine the effects of weight-bearing (WB) versus nonweight-bearing (NWB) exercise for persons with diabetes mellitus (DM) and peripheral neuropathy (PN). DESIGN: Randomized controlled trial with evaluations at baseline and after intervention. SETTING: University-based physical therapy research clinic. PARTICIPANTS: Participants with DM and PN (N=29) (mean age ± SD, 64.5±12.5y; mean body mass index [kg/m(2)] ± SD, 35.5±7.3) were randomly assigned to WB (n=15) and NWB (n=14) exercise groups. All participants (100%) completed the intervention and follow-up evaluations. INTERVENTIONS: Group-specific progressive balance, flexibility, strengthening, and aerobic exercise conducted sitting or lying (NWB) or standing and walking (WB) occurred 3 times a week for 12 weeks. MAIN OUTCOME MEASURES: Measures included the 6-minute walk distance (6MWD) and daily step counts. Secondary outcome measures represented domains across the International Classification of Functioning, Disability and Health. RESULTS: The WB group showed greater gains than the NWB group over time on the 6MWD and average daily step count (P<.05). The mean and 95% confidence intervals (CIs) between-group difference over time was 29m (95% CI, 6-51) for the 6MWD and 1178 (95% CI, 150-2205) steps for the average daily step count. The NWB group showed greater improvements than the WB group over time in hemoglobin A1c values (P<.05). CONCLUSIONS: The results of this study indicate the ability of this population with chronic disease to increase 6MWD and daily step count with a WB exercise program compared with an NWB exercise program.

Task measuring implicit attractiveness as a function of skin tone and facial features: a failed replication.

In two studies, participants completed an implicit attractiveness task with faces as primes varying on (a) facial features from Afrocentric to Eurocentric and (b) skin tone from dark to light, and target pictures of environmental scenes varying in attractiveness. On each trial, participants were briefly primed with a face. Next, they categorized a target picture as either attractive or unattractive as quickly as possible. In addition, in Study 2, participants rated the same faces on an attractiveness scale. While results of Study 1 showed that when faces were medium in skin tone, participants were more accurate when primed with a Eurocentric face responding to attractive targets, but also more accurate when primed with an Afrocentric face responding to unattractive targets, a more powerful Study 2 failed to replicate this effect. There was no relationship between participants' explicit ratings of attractiveness and accuracy rates in the implicit attractiveness task.

Distress Signals: Age Differences in Psychological Distress before and during the COVID-19 Pandemic.

Psychological distress reached historically high levels in 2020, but why, and why were there pronounced age differences? We address these questions using a relatively novel, multipronged approach, part narrative review and part new data analyses. We first updated previous analyses of national surveys that showed distress was increasing in the US and Australia through 2017 and then re-analyzed data from the UK, comparing periods with and without lockdowns. We also analyzed the effects of age and personality on distress in the US during the pandemic. Results showed distress levels and age differences in distress were still increasing through 2019 in the US, UK, and Australia. The effects of lockdowns in 2020 revealed the roles of social deprivation and fear of infection. Finally, age-related differences in emotional stability accounted for the observed age differences in distress. These findings reveal the limitations of analyses comparing pre-pandemic and pandemic periods without accounting for ongoing trends. They also suggest that differences in personality traits such as emotional stability modulate responses to stressors. This could explain age and individual differences in both increases and decreases in distress in response to changes in the level of stressors such as those occurring prior to and during the COVID-19 pandemic.

Myofiber hypertrophy adaptations following 6 weeks of low-load resistance training with blood flow restriction in untrained males and females.

The effects of low-load resistance training with blood flow restriction (BFR) on hypertrophy of type I/II myofibers remains unclear, especially in females. The purpose of the present study is to examine changes in type I/II myofiber cross-sectional area (fCSA) and muscle CSA (mCSA) of the vastus lateralis (VL) from before (Pre) to after (Post) 6 wk of high-load resistance training (HL; n = 15, 8 females) and low-load resistance training with BFR (n = 16, 8 females). Mixed-effects models were used to analyze fCSA with group (HL, BFR), sex (M, F), fiber type (I, II), and time (Pre, Post) included as factors. mCSA increased from pre- to posttraining (P < 0.001, d = 0.91) and was greater in males compared with females (P < 0.001, d = 2.26). Type II fCSA increased pre- to post-HL (P < 0.05, d = 0.46) and was greater in males compared with females (P < 0.05, d = 0.78). There were no significant increases in fCSA pre- to post-BFR for either fiber type or sex. Cohen's d, however, revealed moderate effect sizes in type I and II fCSA for males (d = 0.59 and 0.67), although this did not hold true for females (d = 0.29 and 0.34). Conversely, the increase in type II fCSA was greater for females than for males after HL. In conclusion, low-load resistance training with BFR may not promote myofiber hypertrophy to the level of HL resistance training, and similar responses were generally observed for males and females. In contrast, comparable effect sizes for mCSA and 1-repetition maximum (1RM) between groups suggest that BFR could play a role in a resistance training program.NEW & NOTEWORTHY This is the first study, to our knowledge, to examine myofiber hypertrophy from low-load resistance training with blood flow restriction (BFR) in females. Although this type of training did not result in myofiber hypertrophy, there were comparable increases in muscle cross-sectional area compared with high-load resistance training. These findings possibly highlight that males and females respond in a similar manner to high-load resistance training and low-load resistance training with BFR.

Botulinum toxin effects on gasatrocnemius strength and plantar pressure in diabetics with peripheral neuropathy and forefoot ulceration.

BACKGROUND: High forefoot plantar pressure is associated with plantar ulcers in people with diabetes and peripheral neuropathy. The purpose of this pilot study was to determine the safety and efficacy of botulinum toxin A injected into the gastrocnemius-soleus muscles to reduce muscle strength and plantar pressure. METHODS: This double blind, randomized clinical trial studied 17 people with diabetes mellitus, peripheral neuropathy and a forefoot plantar ulcer. Subjects were randomized into one of three groups receiving gastrocnemius-soleus muscle injections on the involved side with; 1) Saline (n = 5, weight =99± 21 kg), 2) 200-units of Botox® (n = 7, weight = 101± 5 kg), or 3) 300-units of Botox® (n = 5, weight = 129± 22 kg). Botox® dose was converted to units/kg, the majority received between 1.9 and 2.4 units/kg (n = 11) and one 3.2 units/kg. Plantarflexor peak torque and forefoot peak plantar pressure were quantified prior and 2 weeks post-injection. RESULTS: There were no complications from the injections. Plantarflexor peak torque on the involved side increased in the placebo and 300 groups (3± 4 Nm and 6± 10 Nm, respectively) and decreased -8± 11 Nm in the 200 group. There was no relationship between units/kg of Botox® for each subject and change in plantarflexor peak torque. Forefoot peak plantar pressure did not change in the placebo and 300 groups (0± 11 and 0± 5 N/cm(2), respectively) and decreased -4± 16 N/cm2 (4%) for the 200 group. CONCLUSION: There were no adverse events associated with the Botox® injections. This study was unable to determine the dose to consistently reduce plantarflexor strength and forefoot plantar pressure. Additional research is needed to investigate diabetes mellitus specific physiological changes and their impact of BoNT-A effectiveness in order to guide appropriate dosing.

What's in a face? The role of skin tone, facial physiognomy, and color presentation mode of facial primes in affective priming effects.

Participants (N = 106) performed an affective priming task with facial primes that varied in their skin tone and facial physiognomy, and, which were presented either in color or in gray-scale. Participants' racial evaluations were more positive for Eurocentric than for Afrocentric physiognomy faces. Light skin tone faces were evaluated more positively than dark skin tone faces, but the magnitude of this effect depended on the mode of color presentation. The results suggest that in affective priming tasks, faces might not be processed holistically, and instead, visual features of facial priming stimuli independently affect implicit evaluations.

Environmental attitudes, knowledge, intentions and behaviors among college students.

College students (N = 90) reported their pro-environment behaviors as well as their pro-environment intentions, their explicit and implicit attitudes about the environment, and their knowledge about environmental issues. Intentions and knowledge significantly and independently predicted behavior. Environmental knowledge was not significantly related to attitudes. Implicit and explicit attitudes were significantly but only moderately related. Only explicit attitudes, however, were strongly related to intentions, and intentions completely mediated the influence of explicit attitudes on behavior. Men were found to be more knowledgeable than women about environmental issues; older students had more favorable implicit and explicit environmental attitudes. This research suggests that knowledge about the environment and explicit attitudes influence behavior through different pathways, which may have implications for interventions seeking to increase environmentally friendly behavior.

What Can Brinley Plots Tell Us About Cognitive Aging? Exploring Simulated Data and Modified Brinley Plots.

Cognitive aging researchers have been challenged with demonstrating age-related effects above and beyond global slowing ever since Cerella raised this issue in 1990. As the literature has made clear, this has indeed proved to be a difficult task and continues to plague the field. One way that researchers have attempted to test for disproportionate age differences across task conditions is by using Brinley plots, or plotting the mean response latencies of older adults against the mean latencies for younger adults. The simplicity and large proportion of variance accounted for by these models has led to the widespread use of Brinley plots over the years. However, as systematically tested here through eight cases of simulated data, it is clear that the Brinley technique is not well suited to either identify or display the underlying structure of datasets examining age-related differences in attentional control. Some of the problems with conventional Brinley plots can be resolved by using a modified Brinley plot that includes study-specific slopes linking trial types and a no-age-difference reference line. Multilevel models find all of the relevant effects, especially if applied to trial-level data, and have the advantage of incorporating study-level moderators that might account for slope heterogeneity. Ultimately, we encourage fellow cognitive aging researchers to access the code and data for this project on OSF (https://osf.io/zxus8/) and employ the use of multilevel models over Brinley plots.

Differential effects of psychological distress on mitigation and vaccination: A public health conundrum.

CDC-recommended mitigation behaviors and vaccination status were assessed in an online sample (N = 810; ages 18-80). Results were consistent with a differential distress hypothesis positing that whereas psychological distress, which is induced in part by social deprivation, interferes with mitigation behaviors involving social distancing, it motivates vaccination, in part because it, in turn, can increase social interaction. Age modulated these effects. Despite the greater risk of severe consequences, older adults not only showed less distress, but compared to younger participants with equivalent levels of distress, the older adults showed less effect of distress on both social distancing and vaccination status. Together these findings highlight a conundrum faced in public health messaging. Traditional "fear messages" may be less effective for older adults, who are most in danger, whereas in younger adults, the distress induced by fear messages may motivate vaccination but diminish mitigation behaviors needed to prevent subsequent "breakthrough" infections.

Resting interhemispheric functional magnetic resonance imaging connectivity predicts performance after stroke.

OBJECTIVE: Focal brain lesions can have important remote effects on the function of distant brain regions. The resulting network dysfunction may contribute significantly to behavioral deficits observed after stroke. This study investigates the behavioral significance of changes in the coherence of spontaneous activity in distributed networks after stroke by measuring resting state functional connectivity (FC) using functional magnetic resonance imaging. METHODS: In acute stroke patients, we measured FC in a dorsal attention network and an arm somatomotor network, and determined the correlation of FC with performance obtained in a separate session on tests of attention and motor function. In particular, we compared the behavioral correlation with intrahemispheric FC to the behavioral correlation with interhemispheric FC. RESULTS: In the attention network, disruption of interhemispheric FC was significantly correlated with abnormal detection of visual stimuli (Pearson r with field effect = -0.624, p = 0.002). In the somatomotor network, disruption of interhemispheric FC was significantly correlated with upper extremity impairment (Pearson r with contralesional Action Research Arm Test = 0.527, p = 0.036). In contrast, intrahemispheric FC within the normal or damaged hemispheres was not correlated with performance in either network. Quantitative lesion analysis demonstrated that our results could not be explained by structural damage alone. INTERPRETATION: These results suggest that lesions cause state changes in the spontaneous functional architecture of the brain, and constrain behavioral output. Clinically, these results validate using FC for assessing the health of brain networks, with implications for prognosis and recovery from stroke, and underscore the importance of interhemispheric interactions.

Magnetic resonance imaging measurement reproducibility for calf muscle and adipose tissue volume.

PURPOSE: To describe a new semiautomated method for segmenting and measuring the volume of the muscle, bone, and adipose (subcutaneous and intermuscular) tissue in calf muscle compartments using magnetic resonance (MR) images and determine the intrarater and interrater reproducibility of the measures. MATERIALS AND METHODS: Proton-density weighted MR images were acquired from the right calf of 21 subjects. Three raters segmented and measured the volumes of bones, adipose tissue, and five individual muscle compartments. Two raters repeated the segmentations. The intra- and interrater reproducibility of the measures (intraclass correlation coefficients; ICC) were determined using generalizability theory. RESULTS: All ICC values were greater than 0.96. The average standard error of the mean (SEM) of all measures was 1.21 cm(3) and none were greater than 2.3 cm(3) . Essentially all variation (≥97% for all measures) was due to subject differences, indicating low error in the measurements. CONCLUSION: The volumetric measurements for the bones, adipose tissue, and muscle in each of the compartments using MRI were highly reproducible. MRI can provide quantitative, reproducible volumetric measures of bone, adipose tissue, and individual muscle compartments in the calf. We believe these methods can be used to quantify specific muscle or adipose volumetric measures for other clinical or research purposes.