Ecological Factors Impacting Provider Attitudes Towards Human Service Delivery Reform

Although reform efforts are substantially altering the structural operations and guiding ideological framework of the human service delivery system, little empirical work has been done to systematically examine these transformations. This study examines providers' attitudes regarding two reform elements that are being widely implemented: an increased emphasis on inter-agency collaboration and a shift from a medical model service delivery philosophy, that focuses on client deficits, to one that emphasizes consumer strengths. Through survey data collected from 186 providers from 32 human service agencies in one county, the relationship between providers' perceptions of contextual support for human service delivery reform and providers' attitudes towards these initiatives is explored. The findings from this study support the importance of attending to the ecology in which we initiate system reform efforts. For both reform elements, working within contexts that are perceived as providing ideological and functional support for change was associated with positive provider attitudes towards those changes. Staffs' perceptions of the external environment played the most critical role in shaping staff attitudes. Interestingly, unique aspects of providers' work environments were related to positive attitudes towards the two different reforms. The implications of these findings for the success of human service delivery reform are discussed.     

Effect of Stroke on Joint Control during Reach-to-Grasp: A Preliminary Study

Abstract

We investigated changes in control of inter-segmental dynamics underlying upper extremity dyscoordination caused by stroke. Individuals with stroke and healthy individuals performed a natural reach-to-grasp movement. Kinetic analysis revealed that both groups rotated the shoulder by muscle torque and used interaction torque to rotate the elbow. However, individuals with stroke used interaction torque less than healthy individuals, actively suppressing a substantial portion of it. This resulted in inefficient use of active control and dyscoordination of the upper extremity. The degree of interaction torque suppression and inefficiency of active control at the elbow positively correlated with stroke severity. The increased interaction torque suppression can be a strategy used by individuals with stroke to compensate for deficient feedforward control of this torque.     

Visual exploration of reaching space during left and right arm movements in 6-month-old infants

Infant's manual laterality and eye-hand coordination emerge during the second part of the first year of life with the development of reaching. Nevertheless, little is known about the potential asymmetric characteristics of this coordination. The aim of this study was to describe visuo-spatial exploration in 6-month-old infants during reaching, according to the hand used. More specifically, we examined if the use of the left or the right hand was linked to a specific type of visual exploration. Gaze direction during goal-directed reaching towards an object placed on the table was measured with a remote ASL 504 eye tracker (Bedford MA). Twelve babies aged 6 months were observed during six reaching sessions, alterning three sessions with an object on the left side of the subject and three with an object on the right side. Gaze direction and some hand variables (hand activity, hand opening and hand position from the body) were coded with The Observer software. Results showed that babies visually explore their reaching space differently according to the hand used: they look more at the object when they use their right hand and more around the object when they use their left hand; they also look more often at their left hand than at their right one. These results suggest that an asymmetric visuo-manual coordination exists as early as 6 months: vision seems to support (1) left hand during reaching for evaluate distances from object to baby by means of visual feedbacks and (2) right hand for identify what sort of object is. Results are discussed in light of manual specialization and specific hemispheric skills at this age.     

Prehension in children and adults: The effects of object size

Studies of visually goal-directed arm movements in adults have shown that various task constraints such as intention, context, and object properties affect different kinematic characteristics of the movement components (Jeannerod, 1984; MacKenzie et al., 1987; Marteniuk et al., 1987, 1990; Paulignan et al., 1991; Soechting, 1984). The purpose of the present study was to compare the effects of varying object size on the kinematics of reaching and grasping in both children and adults. Five children aged 9–10 years and five adults aged 18–24 years reached for and grasped three different sized cubes. Results revealed that object size had the same effect on the planning and control of reaching and grasping movements in children as in adults. Unlike adults, however, children in this age range spent more time in deceleration and reached peak aperture much later in the movement trajectory. The results were interpreted as immature integration of the visual and proprioceptive systems in 9–10 year olds. The implications of these findings for further examining developmental trends in prehension are discussed.PsycINFO classification: 2330     

Response mode does not modulate the space–time congruency effect: Evidence for a space–time mapping at a conceptual level

Previous studies reported a space–time congruency effect on response time, supporting the notion that people's thinking about time is grounded in their spatial sensorimotor experience. According to a strong view of metaphoric mapping, the congruency effect should be larger for responses that differ in their spatial features than for responses that lack such differences. In contrast, a weaker version of this account posits that the grounding of time is based on higher-level spatial concepts. In this case, response mode should not modulate the size of the space–time congruency effect. In order to assess these predictions, participants in this study responded to temporal stimuli either manually or vocally. Response mode did not modulate the space–time congruency effect which supports the weaker view of metaphoric mapping suggesting that this effect emerges at a higher cognitive level.     

When motor congruency modulates immediate memory for objects

In line with the embodied cognition view, some researchers have suggested that our capacity to retain information relies on the perceptual and motor systems used to interact with our environment (Barsalou, 1999; Glenberg, 1997). For instance, the language production architecture would be responsible for the retention of verbal materials such as a list of words (Acheson & MacDonald, 2009). However, evidence for the role of the motor system in object memory is still limited. In the present experiments, participants were asked to retain lists of objects in memory. During encoding, participants had to pantomime an action to grasp (Experiments 1A & 1B) or to use the objects (Experiment 2) that was either congruent or incongruent with the objects to be retained. The results showed that performing an incongruent action impaired memory performance compared to a congruent action. This suggests that motor affordances play a role during object retention. The results are discussed in light of the embodied cognition view.     

The relationship between reduplicated babble onset and laterality biases in infant rhythmic arm movements

This study examined changes in rhythmic arm shaking and laterality biases in infants observed longitudinally at three points: just prior to, at, and just following reduplicated babble onset. Infants (ranging in age from 4 to 9 months at babble onset) were videotaped at home as they played with two visually identical audible and silent rattles presented at midline for 1.5 min each. Rate of rattle shaking increased sharply from the pre-babble to the babble onset session; but there was no indication that this increase was specific to the right arm. This finding suggests that the link between babble onset and increased rhythmic arm activity may not be the product of language-specific mechanisms, but is rather part of a broader developmental process that is also perceptual and motor.     

Categorization and sensorimotor interaction with objects

Three experiments were aimed at verifying whether the modality of interaction with objects and the goals defined by the task influences the weight of the properties used for categorization. In Experiment 1 we used everyday objects (cups and glasses). In order to exclude that the results depended on pre-stored categorical knowledge and to assess the role of a purely perceptual property such as colour, novel objects were used respectively in Experiment 2 and Experiment 3. Participants experienced objects in different modalities of interaction: Vision, Vision+Action, Action, and Mirror (they observed an experimenter touching and lifting them), then they were submitted to a similarity evaluation task and to a more action-based sorting task. Objects varied in intrinsic properties which had a different degree of interactivity: Grip, Shape, Size and Colour. Overall Grip, the most interactive property, was relevant for categorization, together with Size in Experiment 1 and with Shape in Experiment 2 and Experiment 3. The relevance of Grip in the sorting task confirms that goal-relevant properties are more weighted. The absence of a modality effect is discussed in the framework of the theories arguing that the vision of objects and of conspecifics interacting with objects automatically activates motor information.     

Effects of arm weight on C-not-B task performance: implications for the motor inhibitory deficit account of search failures

Toddlers have been found to fail on a three-location search task involving the invisible displacements of an object, namely the C-not-B task. In this task, a child is shown the experimenter's hand that contains a toy. The toy then successively disappears under the three cloths (A, B, then C). The examiner silently releases the toy under the second cloth (B). The hidden object makes a bump in the B cloth that covers it. Young children emit a strong bias toward the last cloth that the experimenter's hand passes under, and this has been labeled the C-not-B error. One possible explanation for toddlers' failures in the C-not-B task is that children lack the motor inhibitory mechanisms. To test this hypothesis, the robustness of the C-not-B error was tested, in a first experiment, against variations in body parameters. By putting additional weights on the arm, the C-not-B error was reduced substantially and the C-not-B task had a higher rate of success. Indeed, in contrast to control participants, who ignored a visual clue indicating the correct location of the hidden object and reached for the last location of the experimenter's hand, the participants with arm weights initiated their reaching movements by using the visual clue. The findings from the second control group indicate that the dramatic increase in successful performance by children with arm weights is not merely a consequence of the focus on the attention to arm movements. The motion of the experimenter's hand in space appears to have made the task difficult because toddlers had no problems inferring that a lump under a cloth indicates the existence of an object without actually having watched an object be hidden there, as demonstrated in a second experiment. The findings are consistent with the hypothesis that C-not-B task content activates a prepotent motor response that preempts full consideration of a visual clue indicating the correct location of the hidden object. We propose that the success in the C-not-B task of toddlers with additional arm weights could result from a disruption of automatic hand movement that is triggered by sensory signals, namely salient features of the C-not-B task.     

Multitimescale dynamical interactions between speech rhythm and gesture

Temporal patterns in human movement, and in speech in particular, occur on multiple timescales. Regularities in such patterns have been observed between speech gestures, which are relatively quick movements of articulators (e.g., tongue fronting and lip protrusion), and also between rhythmic units (e.g., syllables and metrical feet), which occur more slowly. Previous work has shown that patterns in both domains can be usefully modeled with oscillatory dynamical systems. To investigate how rhythmic and gestural domains interact, an experiment was conducted in which speakers performed a phrase repetition task, and gestural kinematics were recorded using electromagnetic articulometry. Variance in relative timing of gestural movements was correlated with variance in rhythmic timing, indicating that gestural and rhythmic systems interact in the process of planning and producing speech. A model of rhythmic and gestural planning oscillators with multifrequency coupling is presented, which can simulate the observed covariability between rhythmic and gestural timing.