Timing Deficits Research Articles

A single robotic session that guides or increases movement error in survivors post-chronic stroke: which intervention is best to boost the learning of a timing task?

Purpose: Timing deficits can have a negative impact on the lives of survivors post-chronic stroke. Studies evaluating ways to improve timing post stroke are scarce. The goal of the study was to evaluate the impact of a single session of haptic guidance (HG) and error amplification (EA) robotic training interventions on the improvement of post-stroke timing accuracy.Materials and methods: Thirty-four survivors post-chronic stroke were randomly assigned to HG or EA. Participants played a computerized pinball-like game with their affected hand positioned in a robot that either helped them perform better (HG) or worse (EA) during the task. A baseline and retention phase preceded and followed HG and EA, respectively, in order to assess their efficiency at improving absolute timing errors. The impact of the side of the stroke lesion on the participants’ performance during the timing task was also explored for each training group.Results: An improvement in timing performance was only noted following HG (8.9 ± 4.9 ms versus 7.8 ± 5.3 ms, p = 0.032). Moreover, for the EA group only, participants with a left-sided stroke lesion showed a worsening in performance as compared to those with a right-sided stroke lesion (p = 0.001).Conclusion: Helping survivors post-chronic stroke perform a timing-based task is beneficial to learning. Future studies should explore longer and more frequent HG training sessions in order to further promote post stroke motor recovery.Implications for RehabilitationTiming is crucial for the accomplishment of daily tasks.The number of studies dedicated to improving timing is scarce in the literature, even though timing deficits are common post stroke.This innovative study evaluated the impact of a single session of haptic guidance-HG and error amplification-EA robotic training interventions on improvements in timing accuracy among survivors post chronic stroke.HG robotic training improves timing accuracy more than EA among survivors post chronic stroke.

Edaravone improves survival and neurological outcomes after CPR in a ventricular fibrillation model of rats

ObjectiveOverproduction of free radicals is a main factor contributing to cerebral injury after cardiac arrest (CA)/cardiopulmonary resuscitation (CPR). We sought to evaluate the impact of edaravone on the survival and neurological outcomes after CA/CPR in rats. MethodsRats were subjected to CA following CPR. For survival study, the rats with restoration of spontaneous circulation (ROSC) were randomly allocated to one of the two groups (edaravone and saline group, n=20/each group) to received Edaravone (3 mg/kg) or normal saline. Another 10 rats without experiencing CA and CPR served as the sham group. Survival was observed for 72 hours and the neurological deficit score (NDS) was calculated at 12, 24, 48, and 72 hours after ROSC. For the neurological biochemical analysis study, rats were subjected to the same experimental procedures. Then, edaravone group (n=24), saline group (n=24) and sham group (n=16) were further divided into 4 subgroups according to the different time intervals (12, 24, 48, and 72 hours following ROSC). Brain tissues were harvested at relative time intervals for evaluation of oxidative stress, TUNEL staining and apoptotic gene expression. ResultsEdaravone improved postresuscitative survival time and neurological deficit, decreased brain malonylaldehyde level, increased superoxide dismutase activities, decreased proapoptotic gene expression of capase-8, capase-3, and Bax, and increased antiapoptotic Bcl-2 expression at 12, 24, 48, and 72 hours after ROSC. ConclusionsEdaravone improves survival and neurological outcomes following CPR via antioxidative and antiapoptotic effects in rats.

An observational study of implicit motor imagery using laterality recognition of the hand after stroke

Objective: To explore the relationship between laterality recognition after stroke and impairments in attention, 3D object rotation and functional ability.Design: Observational cross-sectional study.Setting: Acute care teaching hospital.Participants: Thirty-two acute and sub-acute people with stroke and 36 healthy, age-matched controls.Main outcome measures: Laterality recognition, attention and mental rotation of objects. Within the stroke group, the relationship between laterality recognition and functional ability, neglect, hemianopia and dyspraxia were further explored.Results: People with stroke were significantly less accurate (69% vs 80%) and showed delayed reaction times (3.0 vs 1.9 seconds) when determining the laterality of a pictured hand. Deficits either in accuracy or reaction times were seen in 53% of people with stroke. The accuracy of laterality recognition was associated with reduced functional ability (R2 = 0.21), less accurate mental rotation of objects (R2 = 0.20) and dyspraxia (p = 0.03).Conclusion: Implicit motor imagery is affected in a significant number of patients after stroke with these deficits related to lesions to the motor networks as well as other deficits seen after stroke. This research provides new insights into how laterality recognition is related to a number of other deficits after stroke, including the mental rotation of 3D objects, attention and dyspraxia. Further research is required to determine if treatment programmes can improve deficits in laterality recognition and impact functional outcomes after stroke.

The role of ecological validity in hazard perception assessment

Hazard perception is one of the few quantifiable components of driving competency that can explain the high crash risk of novice drivers (see Horswill & McKenna, 2004). Some studies focused on investigating the stimulus part of hazard perception items by comparing several design features of the displayed traffic scenarios (e.g. Malone et al., 2012; Scialfa et al., 2013). Other empirical studies have been conducted to address the reaction part of hazard perception items (e.g. Vlakveld, 2014). Among others, existing hazard perception tests differ with respect to the ecological validity – the similarity to real-world demands – of the task that has to be completed by the participants (simple reaction, hazard localization, simulated driving, etc.). Based on the findings of general expertise research (see Glaser & Chi, 1988), the hypothesis of the present experiment was that an increased ecological validity of a hazard perception task has a positive effect on the magnitude of performance differences between more and less experienced drivers. 104 learner drivers and 51 experienced drivers were randomly assigned either to a less ecological valid version (multiple choice task) or a higher ecological valid version (reaction task) of a hazard perception test. In both conditions, the same 20 animated hazardous or non-hazardous traffic scenarios were presented. Overall, the experienced drivers outperformed the learner drivers. Principally, both of the applied versions of the test provided a criterion valid measure of driving expertise. However, increasing the ecological validity of the test by using a reaction task was especially beneficial for certain types of scenarios, leading to higher expertise-related differences. In addition, the reaction task provides response time measure as a further valid performance indicator. This allows the identification of those participants who are indeed able to detect a hazard in a certain scenario, but still have deficits in response time, compared to more experienced drivers. According to the present study, it is recommended to choose the reaction task over the multiple choice task to test hazard perception. Whether a further increase in ecological validity of the task would be useful, should be tested empirically in future research.

Entrepreneurs and Freelancers: Are They Time and Income Multidimensional Poor? The German Case

Entrepreneurs and freelancers, the self-employed, commonly are characterized as not only to be relatively rich in income but also as to be rich in time because of their time-sovereignty in principle. Our introducing study scrutinises these results and notions about the well-being situation of self-employed persons not only by asking about traditional single income poverty but also by considering time poverty within the framework of a new interdependent multidimensional (IMD) poverty concept. The German Socio-economic panel with satisfaction data serves as the data base for the population wide evaluation of the substitution/ compensation between genuine, personal leisure time and income. The available detailed Time Use Surveys of 1991/92 and 2001/2 of the Federal Statistics Office provide the data to quantify the multidimensional poverty in all the IMD poverty regimes. Important result: self-employed with regard to single income poverty, single time poverty and interdependent multidimensional time and income poverty in both years are much more affected by time and income poverty than all other active persons defining the working poor. A significant proportion of non-income-poor but time poor of the active population are not able to compensate their time deficit even by an above poverty income. These people are neglected so far within the poverty and well-being discussion, the discussion about the "working poor" and in the discussion about time squeeze and time pressure in general and in particular for the self-employed as entrepreneurs and freelancers.

Measuring Poverty in the Case of Buenos Aires: Why Time Deficits Matter

We describe the production of estimates of the Levy Institute Measure of Time and Income Poverty (LIMTIP) for Buenos Aires, Argentina, and use it to analyze the incidence of time and income poverty. We find high numbers of hidden poor--those who are not poor according to the official measure but are found to be poor when using our time-adjusted poverty line. Large time deficits for those living just above the official poverty line are the reason for this hidden poverty. Time deficits are unevenly distributed by employment status, family type, and especially gender. Simulations of the impact of full-time employment on those households with nonworking (for pay) adults indicate that reductions in income poverty can be achieved, but at the cost of increased time poverty. Policy interventions that address the lack of both income and time are discussed.

EXPLORATION WELLS COMPLETION IN ICE CONDITIONS OF THE ARCTIC

The article considers the history of development of oil and gas resources of seas and oceans, and prospects of the Arctic off-shore fields development. The analysis of the project solutions on development of the off-shore gas and gas-condensate fields in the Tyumen region north has been carried out. The technology solutions are proposed aimed on completion of prospecting wells from the ice islands at time deficit using drill rigs, as well as on completion of wells with using the preventing units.

Time on timing: Dissociating premature responding from interval sensitivity in Parkinson's disease.

ABSTRACTBackgroundParkinson's disease (PD) can cause impulsivity with premature responses, but there are several potential mechanisms. We proposed a distinction between poor decision‐making and the distortion of temporal perception. Both effects may be present and interact, but with different clinical and pharmacological correlates.ObjectivesThis study assessed premature responding during time perception in PD.MethodsIn this study, 18 PD patients and 19 age‐matched controls completed 2 temporal discrimination tasks (bisection and trisection) and a baseline reaction‐time task. Timing sensitivity and decision‐making processes were quantified by response and response time. An extended version of the modified difference model was used to examine the precision of time representation and the modulation of response time by stimulus ambiguity.ResultsIn the bisection task, patients had a lower bisection point (P < .05) and reduced timing sensitivity when compared with controls (P < .001). In the trisection task, patients showed lower sensitivity in discriminating between short and medium standards (P < .05). The impairment in timing sensitivity correlated positively with patients' levodopa dose equivalent (P < .05). Critically, patients had disproportionately faster response times when compared with controls in more ambiguous conditions, and the degree of acceleration of response time increased with disease severity (P < .05). Computational modeling indicated that patients had poorer precision in time representation and stronger modulation of response time by task ambiguity, leading to smaller scaling of the decision latency (P < .05).ConclusionsThese findings suggest that timing deficits in PD cannot be solely attributed to perceptual distortions, but are also associated with impulsive decision strategies that bias patients toward premature responses. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

The effect of win55, 212-2 on neuronal apoptosis in post-resuscitation in rats

Objective To investigate the pharmacological hypothermic effect of WIN55, 212-2 on neuronal apoptosis after cardiopulmonary resuscitation. Methods Cardiac Arrest (CA) was induced in Sprague-Dawley rats. Five minutes after onset of CA, cardiopulmonary resuscitation (CPR) was carried out. At 30 minutes post-resuscitation, the animals were randomized into three groups (n=10 in each group): (1) WIN55, 212-2 hypothermia group [W group, WIN55, 212-2, 1 mg/(kg·h)]. (2) Normothermia group (NT group, 5% DMSO); (3) WIN55, 212-2 with normothermia group (W+ NT group, WIN55, 212-2, 1 mg/(kg·h). Animals in WIN55, 212-2 hypothermia group and WIN55, 212-2 with normothermia group were dealt with continuous intravenous infusion of WIN55, 212-2[1 mg/(kg·h)] for 4 h, while rats in NT group were infused with equal volume of 5% DMSO instead. The survival time and neurological deficit score (NDS) were observed. The CA models were established in three groups. After rats were sacrificed, the brains were harvested for detecting histopathological changes and apoptosis of neural cell at 24 h, 48 h and 72 h after ROSC respectively. Five animals of each group were chosen randomly(random number). Results Body temperatures of rats in W group decreased from 37°C to 34°C in 4 hours. Accumulated survival rate in W group was higher than that in the other two groups (P=0.02). NDS was significantly improved in W group than that in the other two groups (P<0.05). Morphological change in W group was less serious than that in the other two groups. The number of neuron apoptosis in W group was smaller than that in the other two groups. Conclusions WIN55, 212-2 inducing pharmacologically hypothermia during post-resuscitation prolonged survival and improved cerebral function in rat cardiac arrest models. The beneficial effects of WIN55, 212-2 were associated with ameliorating the histopathological damage in brain and alleviating the neuron apoptosis. Key words: Cardiopulmonary resuscitation; WIN55, 212-2; Pharmacological hypothermia; Apoptosis

Effect of 5-HT2A and 5-HT2C receptors on temporal discrimination by mice

Timing deficits are observed in patients with schizophrenia. Serotonergic hallucinogens can also alter the subjective experience of time. Characterizing the mechanism through which the serotonergic system regulates timing will increase our understanding of the linkage between serotonin (5-HT) and schizophrenia, and will provide insight into the mechanism of action of hallucinogens. We investigated whether interval timing in mice is altered by hallucinogens and other 5-HT2 receptor ligands. C57BL/6J mice were trained to perform a discrete-trials temporal discrimination task. In the discrete-trials task, mice were presented with two levers after a variable interval. Responding on lever A was reinforced if the interval was <6.5 s, and responding on lever B was reinforced if the interval was >6.5 s. A 2-parameter logistic function was fitted to the proportional choice for lever B (%B responding), yielding estimates of the indifference point (T50) and the Weber fraction (a measure of timing precision). The 5-HT2A antagonist M100907 increased T50, whereas the 5-HT2C antagonist SB-242,084 reduced T50. The results indicate that 5-HT2A and 5-HT2C receptors have countervailing effects on the speed of the internal pacemaker. The hallucinogen 2,5-dimethoxy-4-iodoamphetamine (DOI; 3 mg/kg IP), a 5-HT2 agonist, flattened the response curve at long stimulus intervals and shifted it to the right, causing both T50 and the Weber fraction to increase. The effect of DOI was antagonized by M100907 (0.03 mg/kg SC) but was unaffected by SB-242,084 (0.1 mg/kg SC). Similar to DOI, the selective 5-HT2A agonist 25CN-NBOH (6 mg/kg SC) reduced %B responding at long stimulus intervals, and increased T50 and the Weber fraction. These results demonstrate that hallucinogens alter temporal perception in mice, effects that are mediated by the 5-HT2A receptor. It appears that 5-HT regulates temporal perception, suggesting that altered serotonergic signaling may contribute to the timing deficits observed in schizophrenia and other psychiatric disorders.

Perception of the duration of emotional faces in schizophrenic patients.

The level of emotional timing deficit is a critical determinant of daily functions and social interactions in people with schizophrenia. This study demonstrated that people with schizophrenia have significant deficits in emotional time perception. Behaviorally, while the healthy controls overestimated the duration of happy and fearful faces, the patients underestimated the duration of emotional and neutral faces. Accordingly, an online ERP index of timing—the contingent negative variation (CNV) displayed larger amplitudes for emotional faces in the controls, whereas the CNV in the patients only showed overall smaller amplitudes when compared with the controls. In addition, the results of the N170 and the CNV suggest that the emotional processing and timing for facial expressions in schizophrenia might have a pattern of two-stage deterioration. Findings from the present work point to the importance of considering the time dimension of emotional processing in schizophrenia, based on which we are likely to discover aspects of emotional deficits that would be unnoticed in other studies. Furthermore, the perception deviation of the duration of emotional faces in schizophrenia suggests us to consider the magnitude of this temporal deviation as a quantitative biomarker for specific emotional/social dysfunctions in schizophrenia.

Meta-Analysis of Functional Neuroimaging and Cognitive Control Studies in Schizophrenia: Preliminary Elucidation of a Core Dysfunctional Timing Network.

Timing and other cognitive processes demanding cognitive control become interlinked when there is an increase in the level of difficulty or effort required. Both functions are interrelated and share neuroanatomical bases. A previous meta-analysis of neuroimaging studies found that people with schizophrenia had significantly lower activation, relative to normal controls, of most right hemisphere regions of the time circuit. This finding suggests that a pattern of disconnectivity of this circuit, particularly in the supplementary motor area, is a trait of this mental disease. We hypothesize that a dysfunctional temporal/cognitive control network underlies both cognitive and psychiatric symptoms of schizophrenia and that timing dysfunction is at the root of the cognitive deficits observed. The goal of our study was to look, in schizophrenia patients, for brain structures activated both by execution of cognitive tasks requiring increased effort and by performance of time perception tasks. We conducted a signed differential mapping (SDM) meta-analysis of functional neuroimaging studies in schizophrenia patients assessing the brain response to increasing levels of cognitive difficulty. Then, we performed a multimodal meta-analysis to identify common brain regions in the findings of that SDM meta-analysis and our previously-published activation likelihood estimate (ALE) meta-analysis of neuroimaging of time perception in schizophrenia patients. The current study supports the hypothesis that there exists an overlap between neural structures engaged by both timing tasks and non-temporal cognitive tasks of escalating difficulty in schizophrenia. The implication is that a deficit in timing can be considered as a trait marker of the schizophrenia cognitive profile.

Karadeniz Bölgesi için Üçgül (Trifolium sp.) Cinsinin Önemi

There is a high level of forage deficit in Turkey. It is necessary that cultivation and productivity of forage plant should be increase to close forage deficit in a short time, further, pastures should also be improved. Clover genus involves both annual and perennial species, it has some species are grown different soil conditions. Clover species are grown in cool temperate and humid regions have thin stem and abundant leaf, thus, their hay is very nutritive feed for animals. They can use both increasing forage cultivation and pasture improvement in Black Sea Region.

Entrepreneurs and Freelancers: Are They Time and Income Multidimensional Poor? The German Case

Entrepreneurs and freelancers, the self-employed, commonly are characterized as not only to be relatively rich in income but also as to be rich in time because of their time-sovereignty in principle. Our introducing study scrutinises these results and notions about the well-being situation of self-employed persons not only by asking about traditional single income poverty but also by considering time poverty within the framework of a new interdependent multidimensional (IMD) poverty concept. The German Socio-economic panel with satisfaction data serves as the data base for the population wide evaluation of the substitution/ compensation between genuine, personal leisure time and income. The available detailed Time Use Surveys of 1991/92 and 2001/2 of the Federal Statistics Office provide the data to quantify the multidimensional poverty in all the IMD poverty regimes. Important result: self-employed with regard to single income poverty, single time poverty and interdependent multidimensional time and income poverty in both years are much more affected by time and income poverty than all other active persons defining the poor. A significant proportion of non-income-poor but time of the active population are not able to compensate their time deficit even by an above poverty income. These people are neglected so far within the poverty and well-being discussion, the discussion about the working poor and in the discussion about time squeeze and time pressure in general and in particular for the self-employed as entrepreneurs and freelancers.

Temporoparietal encoding of space and time during vestibular-guided orientation.

When we walk in our environment, we readily determine our travelled distance and location using visual cues. In the dark, estimating travelled distance uses a combination of somatosensory and vestibular (i.e., inertial) cues. The observed inability of patients with complete peripheral vestibular failure to update their angular travelled distance during active or passive turns in the dark implies a privileged role for vestibular cues during human angular orientation. As vestibular signals only provide inertial cues of self-motion (e.g., velocity, °/s), the brain must convert motion information to distance information (a process called 'path integration') to maintain our spatial orientation during self-motion in the dark. It is unknown, however, what brain areas are involved in converting vestibular-motion signals to those that enable such vestibular-spatial orientation. Hence, using voxel-based lesion-symptom mapping techniques, we explored the effect of acute right hemisphere lesions in 18 patients on perceived angular position, velocity and motion duration during whole-body angular rotations in the dark. First, compared to healthy controls' spatial orientation performance, we found that of the 18 acute stroke patients tested, only the four patients with damage to the temporoparietal junction showed impaired spatial orientation performance for leftward (contralesional) compared to rightward (ipsilesional) rotations. Second, only patients with temporoparietal junction damage showed a congruent underestimation in both their travelled distance (perceived as shorter) and motion duration (perceived as briefer) for leftward compared to rightward rotations. All 18 lesion patients tested showed normal self-motion perception. These data suggest that the cerebral cortical regions mediating vestibular-motion ('am I moving?') and vestibular-spatial perception ('where am I?') are distinct. Furthermore, the congruent contralesional deficit in time (motion duration) and position perception, seen only in temporoparietal junction patients, may reflect a common neural substrate in the temporoparietal junction that mediates the encoding of motion duration and travelled distance during vestibular-guided navigation. Alternatively, the deficits in timing and spatial orientation with temporoparietal junction lesions could be functionally linked, implying that the temporoparietal junction may act as a cortical temporal integrator, combining estimates of self-motion velocity over time to derive an estimate of travelled distance. This intriguing possibility predicts that timing abnormalities could lead to spatial disorientation.

Risky bicycling behavior among youth with and without attention-deficit hyperactivity disorder.

Injury risk from car-bicycle collisions is particularly high among youth with attention-deficit hyperactivity disorder (ADHD). Here, we capitalized on advances in virtual environment technology to safely and systematically examine road-crossing behavior among child cyclists with and without ADHD. Sixty-three youth (26 with ADHD, 37 non-ADHD controls) ages 10-14years crossed 12 intersections with continuous cross-traffic while riding a high-fidelity bicycling simulator. Traffic density (i.e., temporal gaps between vehicles) was manipulated to examine the impact of varying traffic density on behavioral indices of road crossing, including gap selection, timing of entry into the roadway, time to spare when exiting the roadway, and close calls with oncoming cars. In addition, parents filled out questionnaires assessing their child's ADHD symptomatology, temperamental characteristics, bicycling experience, and injury history. ADHD youth largely chose the same size gaps as non-ADHD youth, although ADHD youth were more likely to select smaller gap sizes following exposure to high-density traffic. In addition, youth with ADHD demonstrated poorer movement timing when entering the intersection, resulting in less time to spare when exiting the roadway. Hyperactivity-impulsivity symptoms were specifically associated with selection of smaller gaps, whereas timing deficits were specifically associated with inattention and inhibitory control. Findings highlight two related yet potentially dissociable mechanisms that may influence injury risk among youth with ADHD and provide a foundation for development of injury prevention strategies.

Language or motor: reviewing categorical etiologies of speech sound disorders.

Language or motor: reviewing categorical etiologies of speech sound disorders.

Quantity of Maternal Time and Child and Adolescent Development: Response to Kalil and Mayer (2016) and to Waldfogel (2016)

Our study of the association between maternal time and developmental outcomes of children and adolescents in the April 2015 issue of Journal of Marriage and Family (Milkie, Nomaguchi, & Denny, 2015a) has drawn much attention, which reflects how strongly researchers and the public care about the relationship between mothers' time and children's well-being. We appreciate the commentaries by Waldfogel (2016) and Kalil and Mayer (2016). Their insights will stimulate research that will further our understanding of maternal and parental time and their relationship to children's and adolescents' well-being.Waldfogel urges investigation of variations in the role of maternal time in influencing child outcomes by social and demographic contexts and suggests examining alternatives to maternal time. We agree and expand on her suggestions in this response. Kalil and Mayer argue that the theoretical framework sets up a straw man. We disagree and briefly articulate how our study derives from aspects of intensive-mothering ideology. Kalil and Mayer emphasize the centrality of mothers' social statuses in shaping children's development and the importance of quality activities for children. These are entirely consistent our conclusions. They are misguided about the interpretation of or quantity of time, however. This is understandable given the complexity of assessing children's time with mothers.In responding to these commentaries, we recap intensive-mothering ideology and the assumptions implied by it. Then we discuss the theoretical and methodological challenges that the commentaries identify, which future research should consider carefully: distinguishing between quantity time and quality of time or activities; conceptualizing children's time mothers compared to alternative time use arrangements; social class and time children; measurement and selection issues; variations by child age, family structure, and child gender; and the role of maternal employment.Intensive Mothering and Its AssumptionsIntensive-mothering ideology places children at the center of mothers' lives and suggests that they require vast amounts of time, effort, and energy from individual mothers (Hallstein, 2006; Hays, 1996). The idea that mothers' time is more valuable for children than is time other caregivers is also an aspect of intensive mothering. Although Kalil and Mayer contend that lower socioeconomic status (SES) mothers do not believe in intensive mothering, studies have shown that they are subject to the same cultural ideal of motherhood as are higher SES mothers (Hays, 1996). Lower SES mothers express the importance of being there and sacrifice as the virtue of good mothering (Damaske, 2011; Edin & Kefalas, 2005; Macdonald, 2009), some of the central elements of intensive-mothering ideology. Regardless of variations in how much people buy into this ideology, it is dominant in the United States (Hays, 1996). Moreover, the debates on maternal employment and the rich history of studying its effects on children deriving from sociological and developmental theories are closely linked to the assumption that the lower quantity of mothers' time allocations to child care is detrimental for children (Bianchi, 2000).Kalil and Mayer repeatedly question our statement on the consequences of intensive mothering ideology for mothers' distress, a topic that motivated the present analysis but was not the focus of it. It is important to distinguish between the ideology of intensive mothering, the actual practice of parenting, and feelings about time children. Intensive-mothering ideology places very high standards on mothers in terms of the appropriate amount of time they should spend their children, which may link to the fact that nearly half of mothers feel as if they are not spending enough time children (Milkie, Mattingly, Nomaguchi, Bianchi, & Robinson, 2004). Importantly, our prior work shows that the feeling of a time deficit children is a strong predictor of poorer maternal well-being (Milkie, Kendig, Nomaguchi, & Denny, 2010; Nomaguchi, Milkie, & Bianchi, 2005). …

Evidence That Bimanual Motor Timing Performance Is Not a Significant Factor in Developmental Stuttering.

Stuttering involves a breakdown in the speech motor system. We address whether stuttering in its early stage is specific to the speech motor system or whether its impact is observable across motor systems. As an extension of Olander, Smith, and Zelaznik (2010), we measured bimanual motor timing performance in 115 children: 70 children who stutter (CWS) and 45 children who do not stutter (CWNS). The children repeated the clapping task yearly for up to 5 years. We used a synchronization-continuation rhythmic timing paradigm. Two analyses were completed: a cross-sectional analysis of data from the children in the initial year of the study (ages 4;0 [years;months] to 5;11) compared clapping performance between CWS and CWNS. A second, multiyear analysis assessed clapping behavior across the ages 3;5-9;5 to examine any potential relationship between clapping performance and eventual persistence or recovery of stuttering. Preschool CWS were not different from CWNS on rates of clapping or variability in interclap interval. In addition, no relationship was found between bimanual motor timing performance and eventual persistence in or recovery from stuttering. The disparity between the present findings for preschoolers and those of Olander et al. (2010) most likely arises from the smaller sample size used in the earlier study. From the current findings, on the basis of data from relatively large samples of stuttering and nonstuttering children tested over multiple years, we conclude that a bimanual motor timing deficit is not a core feature of early developmental stuttering.

Neurobehavioral Anomalies in the Pitx3/ak Murine Model of Parkinson's Disease and MPTP.

Pitx3/ak null mutants are characterized by basal ganglia pathology in a manner resembling Parkinson's disease (PD), with decline in substantia nigra cell numbers as well as striatal tyrosine hydroxylase expression. Although young adult Pitx3/ak mutants were deficient in motor coordination tests, they were more active than non-transgenic controls in the open-field, unlike PD-related bradykinesia. On the SHIRPA primary screen, the mutants displayed body tremor, hyperactivity in the viewing jar, anomalies in eye morphology as well as a higher degree of hindlimb clasping and myoclonic jumping. Increased hindlimb clasping time and rotorod deficits seen in mutants were also exhibited by mice injected with MPTP, indicating an influence of dopamine on these behaviors.