Taxonomic Interference Associated with Phonemic Paraphasias in Agrammatic Primary Progressive Aphasia.

Phonemic paraphasias are thought to reflect phonological (post-semantic) deficits in language production. Here we present evidence that phonemic paraphasias in non-semantic primary progressive aphasia (PPA) may be associated with taxonomic interference. Agrammatic and logopenic PPA patients and control participants performed a word-to-picture visual search task where they matched a stimulus noun to 1 of 16 object pictures as their eye movements were recorded. Participants were subsequently asked to name the same items. We measured taxonomic interference (ratio of time spent viewing related vs. unrelated foils) during the search task for each item. Target items that elicited a phonemic paraphasia during object naming elicited increased taxonomic interference during the search task in agrammatic but not logopenic PPA patients. These results could reflect either very subtle sub-clinical semantic distortions of word representations or partial degradation of specific phonological word forms in agrammatic PPA during both word-to-picture matching (input stage) and picture naming (output stage). The mechanism for phonemic paraphasias in logopenic patients seems to be different and to be operative at the pre-articulatory stage of phonological retrieval. Glucose metabolic imaging suggests that degeneration in the left posterior frontal lobe and left temporo-parietal junction, respectively, might underlie these different patterns of phonemic paraphasia.

What is a task? An ideomotor perspective.

Although multitasking has been the subject of a large number of papers and experiments, the term task is still not well defined. In this opinion paper, we adopt the ideomotor perspective to define the term task and distinguish it from the terms goal and action. In our opinion, actions are movements executed by an actor to achieve a concrete goal. Concrete goals are represented as anticipated sensory consequences that are associated with an action in an ideomotor manner. Concrete goals are nested in a hierarchy of more and more abstract goals, which form the context of the corresponding action. Finally, tasks are depersonalized goals, i.e., goals that should be achieved by someone. However, tasks can be assigned to a specific person or group of persons, either by a third party or by the person or the group of persons themselves. By accepting this assignment, the depersonalized task becomes a personal goal. In our opinion, research on multitasking needs to confine its scope to the analysis of concrete tasks, which result in concrete goals as anticipated sensory consequences of the corresponding action. We further argue that the distinction between dual- and single-tasking is dependent on the subjective conception of the task assignment, the goal representation and previous experience. Finally, we conclude that it is not the tasks, but the performing of the tasks, i.e. the actions that cause costs in multitasking experiments.

"Optimal suppression" as a solution to the paradoxical cost of multitasking: examination of suppression specificity in task switching.

Switching between tasks necessitates maintaining tasks in high readiness, yet readiness creates paradoxical interference from these tasks when they are not currently required. "Optimal suppression", which targets just the interfering information, provides a partial solution to this paradox. By examining the carryover of suppression of a competitor stimulus-response (S-R) set from Trial N - 1 to Trial N, Meiran, Hsieh  and colleagues (Meiran  et al., J Exp Psychol Learn mem cognit 36:992-1002, 2010; Cognit Affect Behav Neurosci 11:292-308, 2011, and Hsieh et al., Acta Psychol 141:316-321, 2012) found that only the competing stimulus-response (S-R) set of rules is suppressed. Specifically, they found that a competitor S-R set in Trial N - 1 incurs cost when it becomes the relevant set in Trial N [competitor becomes relevant (CbR)]. Extending this logic, we predicted performance benefit when the competitor S-R set in Trial N - 1 remains the competitor S-R set in Trial N [competitor remains competitor (CrC)]. Here, we examined the question of whether what is being suppressed when encountering a response conflict is the entire S-R set of rules (e.g., "IF pink PRESS right", and "IF blue PRESS left") or an even more specific representation, namely, the currently interfering S-R rule (e.g., just "IF blue PRESS left"). We show that both CbR and CrC interact with Response (i.e., left or right key), suggesting that the system can recognize the exact source of interference (the competing S-R rule), and inhibit only this source.

The impact of free-order and sequential-order instructions on task-order regulation in dual tasks.

Dual tasks (DTs) are characterized by the requirement for additional mechanisms that coordinate the processing order of two temporally overlapping tasks. These mechanisms are indicated by two types of costs that occur when comparing DT blocks with fixed and random orders of the component tasks. On a block level, task-order control costs are reflected in increased reaction times (RTs) in random-order compared to fixed-order blocks, indicating global, monitoring-based, coordination mechanisms. On a trial level, within random-order blocks, order-switch costs are indicated by increased RTs on order switch compared to order repetition trials, reflecting memory-based mechanisms that guide task-order in DTs. To test the nature of these mechanisms in two experiments, participants performed DTs in fixed- and random-order blocks. In random-order blocks, participants were either instructed to respond to both tasks according to the order of task presentation (sequential-order instruction) or instructed to freely decide in which order to perform both tasks (free-order instruction). As a result of both experiments, we demonstrated that task-order control costs were reduced under the free-order compared to the sequential-order instruction, whereas order-switch costs were not affected by our instruction manipulation. This pattern of results suggests that the task-order control costs reflect global processes of task-order regulation such as engaging monitoring processes that are sensitive to changes in order instructions, while order-switch costs reflect rather local memory-based mechanisms that occur irrespective of any effort to coordinate task-order.

Multitasking as a choice: a perspective.

Performance decrements in multitasking have been explained by limitations in cognitive capacity, either modelled as static structural bottlenecks or as the scarcity of overall cognitive resources that prevent humans, or at least restrict them, from processing two tasks at the same time. However, recent research has shown that individual differences, flexible resource allocation, and prioritization of tasks cannot be fully explained by these accounts. We argue that understanding human multitasking as a choice and examining multitasking performance from the perspective of judgment and decision-making (JDM), may complement current dual-task theories. We outline two prominent theories from the area of JDM, namely Simple Heuristics and the Decision Field Theory, and adapt these theories to multitasking research. Here, we explain how computational modelling techniques and decision-making parameters used in JDM may provide a benefit to understanding multitasking costs and argue that these techniques and parameters have the potential to predict multitasking behavior in general, and also individual differences in behavior. Finally, we present the one-reason choice metaphor to explain a flexible use of limited capacity as well as changes in serial and parallel task processing. Based on this newly combined approach, we outline a concrete interdisciplinary future research program that we think will help to further develop multitasking research.

[Characteristics of central nervous system activity in patients with complications of arterial hypertension and dependence on psychomotor status and treatment].

Changes in certain CNS characteristics were used as indicators of the efficacy of antihypertensive therapy (AHT) both targeted (T-AHT) and empirical (E-AHT) designed to suppress activity of the sympathetic component of vegetative nervous system (VNS) and renin-angiotensin-aldosterone system (RAAS) in patients of different psychic status and AH. A group of 835 men (mean age 54.2+-1.8yr) was divided into cholerics, sanguinics, melancholics and phlegmatics with a high and low anxiety level (HA and LA). 416 healthy men served as controls. The following parameters were estimated: mobility of cortical processes, balance between sympathetic and parasympathetic activities, blood corrisol and aldosterone levels, oxygen utilization coefficient, resistance to breath holding, severity of dyscirculatory encephalopathy and the fraction of patients with AH complications during 12 month T-AHT for the suppression of sympathetic activity in cholerics and sanguinics by beta-adrenoblockers and PAA C- ACE inhibitors in phlegmatics and melancholics and during E-AHT (ACE inhibitors in cholerics and sanguinics, BAB in phlegmatics and melancholics). The functional activity of CNS in phlegmatics and melancholics before and during AHT was lower and severity of encephalopathy and the number ofAH complications higher than in cholerics and sanguinics. . The changes wiere more pronounced in patients with HA than in those with LA. Unlike E-AHT T-AHT (anxiolytics for cholerics and sanguinics with HA, antidepressants for phlegmatics and melancholics with HA) normalized the study parameters and decreased the frequency of complications by 2-3 times.

Validity and reliability of a radio positioning system for tracking athletes in indoor and outdoor team sports.

Radio-frequency local positioning systems (LPS) have the potential to provide accurate location information about sport players for performance analysis, making available for study the emergent nature of interpersonal coordination and collective decision-making behaviour among players in both indoor and outdoor sports. However, no available publications have validated the performance of LPS for indoor sports. The objective of this study was to validate the performance of an LPS in an indoor venue and to compare it to performance observed in an outdoor venue using static and dynamic measurements. Our results showed that the absolute positioning errors obtained from the static measurements of the LPS were comparable for both indoor and outdoor venues, with mean errors of 12.1 cm outdoors and 11.9 cm indoors. From the dynamic measurements, we analysed the relative position error and the distance estimation performance of the system. The 90th-percentile relative position errors were 28 cm for the indoor venue versus 18 cm for the outdoor venue. On average, the LPS overestimated the distance travelled, and the performance was similar for both indoor and outdoor venues. On a linear course, the mean errors of the distance estimates were 2.2% of the total distance indoors and 1.3% outdoors, and on a nonlinear course, they were 2.7% indoors and 3.2% outdoors.

Assessing visually guided reaching in people with multiple sclerosis with and without self-reported upper limb impairment.

The ability to accurately complete goal-directed actions, such as reaching for a glass of water, requires coordination between sensory, cognitive and motor systems. When these systems are impaired, like in people with multiple sclerosis (PwMS), deficits in movement arise. To date, the characterization of upper limb performance in PwMS has typically been limited to results attained from self-reported questionnaires or clinical tools. Our aim was to characterize visually guided reaching performance in PwMS. Thirty-six participants (12 PwMS who reported upper limb impairment (MS-R), 12 PwMS who reported not experiencing upper limb impairment (MS-NR), and 12 age- and sex-matched control participants without MS (CTL)) reached to 8 targets in a virtual environment while seeing a visual representation of their hand in the form of a cursor on the screen. Reaches were completed with both the dominant and non-dominant hands. All participants were able to complete the visually guided reaching task, such that their hand landed on the target. However, PwMS showed noticeably more atypical reaching profiles when compared to control participants. In accordance with these observations, analyses of reaching performance revealed that the MS-R group was more variable with respect to the time it took to initiate and complete their movements compared to the CTL group. While performance of the MS-NR group did not differ significantly from either the CTL or MS-R groups, individuals in the MS-NR group were less consistent in their performance compared to the CTL group. Together these findings suggest that PwMS with and without self-reported upper limb impairment have deficits in the planning and/or control of their movements. We further argue that deficits observed during movement in PwMS who report upper limb impairment may arise due to participants compensating for impaired movement planning processes.

Participation, self-concept and motor performance of boys with developmental coordination disorder: a classification and regression tree analysis approach.

AIM: Identification of relationships between participation, psycho-social adjustment and motor performance factors in boys with developmental coordination (DCD) using a classification and regression tree approach to determine patterns of potential vulnerability. METHODS: A quantitative cross-sectional design investigating a cohort of 60 boys aged 10-13 years with DCD was employed. Classification and regression tree analysis of: (i) fundamental movement skill performance on tests of balance, ball skills and manual dexterity, (ii) self-concept perceptions and (iii) leisure-time activity participation, was used to define different risk groups. RESULTS AND CONCLUSION: Five meaningful groups of boys were identified. Poor manual dexterity was the strongest discriminator of group membership in the three most severely affected groups confirming the significance of fine motor difficulties as a key grouping variable and supporting previous research using cluster analyses. Low participation in out-of-school informal social-physical activities was found to be a new grouping factor alongside poor peer relations self-concept. A final group describing boys with poor motor performance across all fundamental movement skill areas who had high participation in structured social non-physical activities, such as choir or band, was identified. The potential for future classification and regression tree analyses to inform clinical decision making was discussed.

The Italian version of the Hand Mobility in Scleroderma (HAMIS) test: evidence for its validity and reliability.

OBJECTIVES: In systemic sclerosis (SSc), hand involvement is frequent and leads to prominent disability. The Hand Mobility in Scleroderma (HAMIS) test is a hand function test for SSc patients assessing the movements included in an ordinary range of motion examination. Our aim is to validate the Italian version of HAMIS, by assessing its test-retest reliability, internal consistency and external consistency in Italian SSc patients. METHODS: The Italian version of HAMIS was administered to 40 SSc patients. HAMIS was translated according to international procedures. Test-retest reliability was assessed by intra-class correlation coefficient (ICC), internal consistency by Cronbach's alpha and external consistency by comparison with Cochin Hand Function Scale (CHFS), fist closure, hand opening, HAQ. RESULTS: HAMIS showed a good testretest reliability (ICCs=0.99 for right and left hand) and internal consistency (Cronbach's α=0.94 for right and 0.93 for left hand) for both hands. A good external consistency was confirmed by the correlation of right and left hand HAMIS with CHFS (p<0.0001, in both cases); fist closure of homolateral hand (p<0.0001 in both cases), opening of homolateral hand (p<0.05 and <0.005, respectively), HAQ (p<0.001 in both cases). HAMIS scores for right and left hands were 7.95±6 .68 and 7.5±6.60 (p=NS), respectively. HAMIS scores for both hands were higher in dSSc and in patients with hand arthritis and flexion contractures. CONCLUSIONS: HAMIS is a hand function test measuring hand disability in SSc. Our results support its validity and reliability in Italian SSc patients.

Interrater reliability of goal attainment scaling in rehabilitation of children with cerebral palsy.

OBJECTIVES: To determine the interrater reliability of Goal Attainment Scaling (GAS) in the routine practice of interdisciplinary rehabilitation of children with cerebral palsy, and to examine the difference in the interrater reliability of the scores between GAS scales constructed by the children's own therapists and the scales constructed by independent therapists. DESIGN: Individually tailored GAS scales, based on predetermined criteria, were constructed at the start of a 6-month rehabilitation period. The outcome was rated independently by 2 therapists at the end of the treatment period. Two different data sets were acquired, one consisting of scores on GAS scales constructed by the children's own therapists, the other of scores on GAS scales constructed by matched independent raters of the same profession. SETTING: A children's unit of a medium-sized rehabilitation center in The Netherlands. PARTICIPANTS: Physical therapists (n=8), occupational therapists (n=8), and speech therapists (n=4) participated in pairs. They constructed 2 sets of 64 GAS scales each, for 23 children with cerebral palsy. INTERVENTIONS: A 6-month interdisciplinary pediatric rehabilitation program. MAIN OUTCOME MEASURE: Interrater reliability was assessed using linear-weighted Cohen's kappa. RESULTS: The scales constructed by the children's therapists had an interrater reliability of .82 (95% confidence interval [CI], .73-.91). The interrater reliability for scales constructed by the independent raters was .64 (95% CI, .49-.79). The main reason for disagreement between raters was discrepancies in the professionals' interpretation of the children's capacities versus their actual performance during assessment. CONCLUSIONS: The interrater reliability of GAS used under optimal conditions was good, particularly for scales constructed by the children's own therapists.

[Retrospective assessment of health and locomotor efficiency in elderly patients in the period directly preceding femoral trochanter fracture]. / Retrospektywna ocena stanu zdrowia i sprawnosci motorycznej chorych w wieku podeszlym w okresie bezposrednio poprzedzajacym wystapienie zlamania kretarzowego kosci udowej.

This paper presents a group of patients which had femoral trochanter fracture. The study group was assessed in terms of age, sex, concomitant diseases and pre-traumatic motor efficiency. The author of the paper highlights the fact that the majority (42%) of patients is over 80 years of age, and frequently suffer from two or more concomitant diseases impeding the surgical procedure in the emergency mode. Moreover almost every second person had significant problems with movement before the fracture.

Gross motor performance and self-perceived motor competence in children with emotional, behavioural, and pervasive developmental disorders: a review.

AIMS: Motor performance and self-perceived motor competence have a great impact on the psychosocial development of children in general. In this review, empirical studies of gross motor performance and self-perception of motor competence in children with emotional (depression and anxiety), behavioural, and pervasive developmental disorders are scrutinized, with the objective of identifying specific motor characteristics that may be relevant to clinical practice. METHOD: A systematic search of studies published between 1997 and 2007 was performed using nine search engines. RESULTS: Children in all three categories (emotional, behavioural, and pervasive developmental disorders) exhibit poor gross motor performance and problematic self-perception of motor competence, with certain indications of disorder-specific characteristics. In particular, children with emotional disorders have balance problems and self-perceived motor incompetence; children with behavioural disorders show poor ball skills and tend to overestimate their motor performance; children with pervasive developmental disorders demonstrate poor gross motor performance and self-perceived motor incompetence. As a result, children with developmental and emotional disorders are restricted in participating in games and play, which may lead to inactive lifestyles and further disruption of their psychosocial and physical development. INTERPRETATION: Motor problems need more, to some extent disorder-specific, attention in clinical practice than has been provided to date.

Motor function in 5-year-old children with cerebral palsy in the South Australian population.

The aim of this study was to describe the motor function of a population of children at age 5 years enrolled on the South Australian Cerebral Palsy Register. Among children born between 1993 and 1998, there were 333 with confirmed cerebral palsy (prevalence rate 2.2 per 1000 live births), in whom 247 assessments (56.7% males, 43.3% females) were completed. The distribution by Gross Motor Function Classification System (GMFCS) level was: level I, 50.6%; level II, 18.2%; level III, 9.3%; level IV, 9.7%; level V, 12.1%. The most common topographical classification was spastic diplegia (38.5%), followed by spastic hemiplegia (34.8%) and spastic quadriplegia (14.6%). Abnormal movements occurred at rest or with intention in 19.4% of children. A high proportion of the population with relatively mild gross motor impairments have difficulty with everyday bimanual tasks, reinforcing the need to assess upper limb function independently of gross motor function. The use of ankle-foot orthoses was common, particularly across GMFCS levels II to IV. Further refinement is indicated for this population's motor dataset, to include more recently described classification measures as well as future novel measures to better describe the presence of both spasticity and dystonia.

Patterns of hand preference for pairs of actions and the classification of handedness.

Pairs of actions such as write x throw and throw x racquet were examined for items of the Annett hand preference questionnaire (AHPQ). Right (R) and left (L) responses were described for frequencies of RR, RL, LR, and LL pairings (write x throw etc.) in a large representative combined sample with the aim of discovering the distribution over the population as a whole. The frequencies of RL pairings varied significantly over the different item pairs but the frequencies of LR pairings were fairly constant. An important difference was found between primary actions (originally write, throw, racquet, match, toothbrush, hammer with the later addition of scissors for right-handers) and non-primary actions (needle and thread, broom, spade, dealing playing cards, and unscrewing the lid of a jar). For primary actions, there were similar numbers of right and left writers using the 'other' hand. For non-primary actions more right-handers used the left hand than for primary actions but more left-handers did not use the right hand. That is, different frequencies of response to primary versus non-primary actions were found for right-handers but not for left-handers. The pattern of findings was repeated for a corresponding analysis of left-handed throwing x AHPQ actions. The findings have implications for the classification of hand preferences and for analyses of the nature of hand skill.

Spiral drawing time as a measure of bradykinesia.

BACKGROUND AND PURPOSE: Bradykinesia, which is commonly defined as slowness of movements, is one of the cardinal signs of Parkinson's disease (PD) and parkinsonian syndromes. Simple clinical rating scales are used commonly to measure bradykinesia in routine clinical practice although this kind of assessment is biased. The aim of the study was to evaluate the time of spiral drawing as a measure of bradykinesia. MATERIAL AND METHODS: Fifty-four patients with PD and 39 healthy age- and sex-matched volunteers were examined. The severity of parkinsonism was assessed using UPDRS and bradykinesia was assessed using instrumental methods: the BRAIN test, Nine-Hole Peg Board (NHPB) test and Quantitative Tremor Analysis on the Graphic Digitizing Tablet (QTAGDT). QTAGDT registers patients' hand movements during the spiral drawing task and generates several data characterizing tremor and the spiral drawing time as an additional result. RESULTS: The spiral drawing time was significantly longer in PD patients when compared to normal controls (p <0.001). The bradykinesia assessment using the spiral drawing time showed a significant correlation with the clinical rating score of the UPDRS (R = 0.64, p = 0.001) and with the results of other instrumental methods: the BRAIN Test and NHPB test (R = -0.52, p = 0.0007, R = 0.55, p = 0.03, respectively). Hand tremor seemed to have no impact on bradykinesia assessment, and the new method was found to be highly test-retest reliable (R = 0.95, p < 0.0001). CONCLUSION: The spiral drawing time is a simple, quick and objective assessment of upper limb bradykinesia.

Distinguishing Patients With a Coordination Disorder From Healthy Controls Using Local Features of Movement Trajectories During the Finger-to-Nose Test.

Assessment of coordination disorders is valuable for monitoring progression of patients, distinguishing healthy and pathological conditions, and ultimately aiding in clinical decision making, thereby offering the possibility to improve medical care or rehabilitation. A common method to assess movement disorders is by using clinical rating scales. However, rating scales depend on the evaluation and interpretation of an observer, implying that subjective phenotypic assignment precedes the application of the scales. Objective and more accurate methods are under continuous development but gold standards are still scarce. Here, we show how a method we previously developed, originally aimed at assessing dynamic balance by a probabilistic generalized linear model, can be used to assess a broader range of functional movements. In this paper, the method is applied to distinguish patients with coordination disorders from healthy controls. We focused on movements recorded during the finger-to-nose task (FNT), which is commonly used to assess coordination disorders. We also compared clinical FNT scores and model scores. Our method achieved 84% classification accuracy in distinguishing patients and healthy participants, using only two features. Future work could entail testing the reliability of the method by using additional features and other clinical tests such as finger chasing, quiet standing, and/or usage of tracking devices such as depth cameras or force plates.

Inconsistencies with physical functioning and the child health questionnaire in children with cerebral palsy.

OBJECTIVES: To explore the performance of the Physical Functioning (PF) subscale of the Child Health Questionnaire (CHQ) in children with cerebral palsy (CP). STUDY DESIGN: Parents of 177 children and adolescents (age 3 to 18 years) with CP completed the CHQ -Parent Form 50. Severity of CP was assessed using the 5-level Gross Motor Function Classification System (GMFCS), in which higher levels reflect more severe impairment. RESULTS: PF scores were negatively correlated with GMFCS classification (R = -0.62) and were distributed bimodally in subjects with severe motor impairment. For GMFCS classifications IV and V (n = 59), PF scores were very low (means, 9 to 28; medians, 0 to 8); however, 12% of these subjects had excellent PF scores (> 88) despite being nonambulatory. CONCLUSIONS: Although the CHQ PF subscale correlated well with the GMFCS, the CHQ questions on physical functioning resulted in unexpected responses in approximately 1 in 8 subjects with severe CP. These unanticipated responses to the PF subscale questions may be due to ambiguity in the questions (which do not differentiate between health problems and disability) or to alternative parental interpretation of physical functioning. Confusion in differentiating health status and functional status may make the CHQ less useful in children with significant disabilities.

Cognitive representations of disability behaviours in people with mobility limitations: consistency with theoretical constructs.

PURPOSE: Disability is conceptualized as behaviour by psychological theory and as a result of bodily impairment by medical models. However, how people with disabilities conceptualize those disabilities is unclear. The purpose of this study was to examine disability representations in people with mobility disabilities. METHOD: Thirteen people with mobility disabilities completed personal repertory grids (using the method of triads) applied to activities used to measure disabilities. Ten judges with expertise in health psychology then examined the correspondence between the elicited disability constructs and psychological and medical models of disability. RESULTS: Participants with mobility disabilities generated 73 personal constructs of disability. These constructs were judged consistent with the content of two psychological models, namely the theory of planned behaviour and social cognitive theory and with the main medical model of disability, the International Classification of Functioning Disability and Health. CONCLUSIONS: Individuals with activity limitations conceptualize activities in a manner that is compatible with both psychological and medical models. This ensures adequate communication in contexts where the medical model is relevant, e.g., clinical contexts, as well as in everyday conversation about activities and behaviours. Finally, integrated models of disability may be of value for theory driven interdisciplinary approaches to disability and rehabilitation.

Evaluation of gross motor abilities and self perception in children with amblyopia.

PURPOSE: The present study evaluates gross motor abilities and self perception about the physical abilities of pre-school children with amblyopia, in comparison to their unaffected peers. METHOD: Twenty-two children with amblyopia, and 25 children with normal vision, aged 4-7, were included in this study. Gross motor abilities were evaluated by the Movement Assessment Battery for Children (MABC). The Pictorial Scale of Perceived Competence and Social Acceptance for Young Children were used to measure physical self perception. Parents completed a questionnaire about everyday situations revolving around the child's balance and posture abilities. RESULTS: Amblyopic children performed significantly worse than the controls according to the MABC subtests and the parents' questionnaire total score. In the scale of perceived competence evaluation the amblyopic children had lower scores in half of the items as well as in the total mean score, but the differences between the groups were not significant. Among the study group, significant correlations were found between several items in the parents' questionnaire and the children's' mean balance score in MABC. CONCLUSIONS: Amblyopia may negatively impact children's motor abilities as expressed by the objective measures in daily living, while self perception is less affected.