Non-invasive brain stimulation for fine motor improvement after stroke: a meta-analysis.

The aim of this study was to determine whether non-invasive brain stimulation (NIBS) techniques improve fine motor performance in stroke. We searched PubMed, EMBASE, Web of Science, SciELO and OpenGrey for randomized clinical trials on NIBS for fine motor performance in stroke patients and healthy participants. We computed Hedges' g for active and sham groups, pooled data as random-effects models and performed sensitivity analysis on chronicity, montage, frequency of stimulation and risk of bias. Twenty-nine studies (351 patients and 152 healthy subjects) were reviewed. Effect sizes in stroke populations for transcranial direct current stimulation and repeated transcranial magnetic stimulation were 0.31 [95% confidence interval (CI), 0.08-0.55; P = 0.010; Tau2 , 0.09; I2 , 34%; Q, 18.23; P = 0.110] and 0.46 (95% CI, 0.00-0.92; P = 0.05; Tau2 , 0.38; I2 , 67%; Q, 30.45; P = 0.007). The effect size of non-dominant healthy hemisphere transcranial direct current stimulation on non-dominant hand function was 1.25 (95% CI, 0.09-2.41; P = 0.04; Tau2 , 1.26; I2 , 93%; Q, 40.27; P < 0.001). Our results show that NIBS is associated with gains in fine motor performance in chronic stroke patients and healthy subjects. This supports the effects of NIBS on motor learning and encourages investigation to optimize their effects in clinical and research settings.

Psychiatric and physical morbidity effects of dementia caregiving: prevalence, correlates, and causes.

The dementia caregiving literature is reviewed with the goals of (a) assessing the prevalence and magnitude of psychiatric and physical morbidity effects among caregivers, (b) identifying individual and contextual correlates of reported health effects and their underlying causes, and (c) examining the policy relevance of observed findings. Virtually all studies report elevated levels of depressive symptomatology among caregivers, and those using diagnostic interviews report high rates of clinical depression and anxiety. The evidence is more equivocal and generally weaker for the association between caregiving and physical morbidity, such as self-rated health, number of illnesses, symptomatology, health care utilization, preventive health behaviors, and cardiovascular functioning. Across studies, psychiatric morbidity in caregivers was linked to patient problem behaviors, income, self-rated health, perceived stress, and life satisfaction. Physical morbidity was associated with patient problem behaviors and cognitive impairment, and with caregiver depression, anxiety, and perceived social support. Possible causes of reported effects and policy implications are discussed.

Fetal pulmonary beta-adrenergic receptors: characterization in the human and in vitro modulation by glucocorticoids in the rabbit.

At least two developmental responses necessary to prepare the fetal lung to serve as a gas-exchange organ, the release of surface-active material and the reabsorption of alveolar water, can be stimulated by beta-adrenergic agonists. The sensitivity of these responses increases dramatically in late gestation. beta-Adrenergic receptors can be identified by radioligand binding and are present in human fetal lung as early as 16 weeks of gestation. The temporal relationship of the increases in both pulmonary beta-receptors and plasma-free cortisol in the fetal rabbit during gestation suggests that endogenous glucocorticoids may cause increased concentration of pulmonary beta-receptors. Treatment of pregnant rabbits at 24 or 25 days of gestation results in precocious increases in both fetal lung beta-receptors and agonist-specific, high-affinity binding. The increase in receptor concentration with glucocorticoid is not dependent on other endocrine response inasmuch as 0.1 microM dexamethasone increases beta-receptor concentrations at 24 and 48 hours of incubation in cultures of fetal rabbit lung organ. This effect of glucocorticoid to increase beta-receptor concentration and high-affinity binding may explain the increased fetal pulmonary beta-adrenergic response at term and may be responsible in part for the reduction in neonatal respiratory syndrome seen after antenatal glucocorticoid therapy.

The solution of anagrams: A reexamination of the effects of transition letter probabilities, letter moves, and word frequency on anagram difficulty.

Word frequency (WF), number of letter moves, and solution word transition letter probabilities (TP) were related to anagram solution. The solution word TP measure was based on the relative frequencies of correct to incorrect bigrams within the pool of bigrams defined by the letters of the anagram rather than on the absolute frequencies of the correct bigrams. This bigram rank measure, which also took word length and letter position into account, was a powerful predictor of anagram difficulty (p < .001). Likewise, number of letter moves predicted anagram solution strongly (p < .001), but WF was only a marginal predictor (.05 < p < .10). In addition, there were no significant interactions among the three variables, nor wasanagram TP consistently related to anagram difficulty. The results were interpreted in terms of an approach which combined elements of an hypothesis and an S-R mediational theory.