Followers are not followed: observed group interactions modulate subsequent social attention

We asked whether previous observations of group interactions modulate subsequent social attention episodes. Participants first completed a learning phase with two conditions. In the ‘leader’ condition one of three identities turned her gaze first, followed by the two other faces. In the ‘follower’ condition, one of the identities turned her gaze after the two other faces had first shifted their gaze. Thus, participants observed that some individuals were consistently ‘leaders’ and others ‘followers’ of others’ attention. In the test phase, the faces of ‘leaders’ and ‘followers’ were presented in a gaze cueing paradigm. Remarkably, the ‘followers’ did not elicit gaze cueing. Our data demonstrate that individuals who do not guide group attention in exploring the environment are ineffective social attention directors in later encounters. Thus, the role played in previous group social attention interactions modulates the relative weight assigned to others’ gaze: we ignore the gaze of group followers.

A home environment test battery for status assessment in patients with motor fluctuations

Background and aims Evaluating status in patients with motor fluctuations is complex and occasional observations/measurements do not give an adequate picture as to the time spent in different states. We developed a test battery to assess advanced Parkinson patients' status consisting of diary assessments and motor tests. This battery was constructed and implemented on a handheld computer with built-in mobile communication. In fluctuating patients, it should typically be used several times daily in the home environment, over periods of about one week. The aim of this battery is to provide status information in order to evaluate treatment effects in clinical practice and research, follow up treatments and disease progression and predict outcome to optimize treatment strategy. Methods Selection of diary questions was based on a previous study with Duodopa® (DIREQT). Tapping tests (with and without visual cueing) and a spiral drawing test were added. Rapid prototyping was used in development of the user interface. An evaluation with two pilot patients was performed before and after receiving new treatments for advanced disease (one received Duodopa® and one received DBS). Speed and proportion missed taps were calculated for the tapping tests and entropy of the radial drawing velocity was calculated for the spiral tests. Test variables were evaluated using non-parametric statistics. Results Post-treatment improvement was detected in both patients in many of the test variables. Conclusions Although validation work remains, preliminary results are promising and the test battery is currently being evaluated in a long-term health economics study with Duodopa® (DAPHNE).

The Effect of Metronome Pacing on Gait in Healthy Subjects

The complex process of gait is rendered partially automatic by central pattern generators (CPGs). To further our understanding of their role in gait control in healthy subjects, we applied a paradigm of anti-phase, or syncopated, movement to gait. To provide a context for our results, we reviewed the literature on in-phase, or synchronized, gait. The review results are as follows. Auditory cueing increased step/stride rate for older subjects, but not younger. Stride rate variability decreased for younger subjects, perhaps because the metronome’s cue acted as a temporal ‘anchor point’ for each step. Step width increased in half of the treadmill studies, but none of the overground ones, suggesting a cumulative effect of the attentional demands of synchronizing gait while on a treadmill. Time series analysis revealed that the α exponent was the most sensitive parameter reported, decreasing toward anti-persistence in almost all cued-gait studies. This project compares in-phase (IN) and anti-phase gait (ANTI) in young and old healthy subjects. We expected gait to be less disrupted during ANTI trials at preferred speed, when the facilitating effect of CPGs would be strongest. The measures step time variability, jerk index, and harmonic ratio quantified gait perturbation: none indicated that ANTI was easiest at preferred walking speed. Surprisingly, the gait of older subjects was no more perturbed than that of younger subjects. When they successfully matched the pace of the beat, they unwittingly synchronized to it. The temporal relationship of their steps to the beat was the same in the IN and ANTI conditions. Younger subjects, visibly struggling during ANTI trials, were able to walk in syncopation. This result suggests that cognitive resources available only to the younger group are required to resist synchronizing to the beat.

Bone-implant interface. Evaluation of osteoblastic cells behavior on nanopatterned titanium surfaces: an in vitro analysis

Protein-adsorption occurs immediately following implantation of biomaterials. It is unknown at which extent protein-adsorption impacts the cellular events at bone-implant interface. To investigate this question, we compared the in-vitro outcome of osteoblastic cells grown onto titanium substrates and glass as control, by modulating the exposure to serum-derived proteins. Substrates consisted of 1) polished titanium disks; 2) polished disks nanotextured with H2SO4/H2O2; 3) glass. In the pre-adsorption phase, substrates were treated for 1h with αMEM alone (M-noFBS) or supplemented with 10%-foetal-bovine-serum (M-FBS). MC3T3-osteoblastic-cells were cultured on the pre-treated substrates for 3h and 24h, in M-noFBS and M-FBS. Subsequently, the culture medium was replaced with M-FBS and cultures maintained for 3 and 7days. Cell-number was evaluated by: Alamar-Blue and MTT assay. Mitotic- and osteogenic-activities were evaluated through fluorescence-optical-microscope by immunolabeling for Ki-67 nuclear-protein and Osteopontin. Cellular morphology was evaluated by SEM-imaging. Data were statistically analyzed using ANOVA-test, (p<0.05). At day3 and day7, the presence or absence of serum-derived proteins during the pre-adsorption phase had not significant effect on cell-number. Only the absence of FBS during 24h of culture significantly affected cell-number (p<0.0001). Titanium surfaces performed better than glass, (p<0.01). The growth rate of cells between day3 and 7 was not affected by the initial absence of FBS. Immunolabeling for Ki-67 and Osteopontin showed that the mitotic- and osteogenic- activity were ongoing at 72h. SEM-analysis revealed that the absence of FBS had no major influence on cell-shape. • Physico-chemical interactions without mediation by proteins are sufficient to sustain the initial phase of culture and guide osteogenic-cells toward differentiation. • The challenge is avoiding adsorption of ‘undesirables’ molecules that negatively impact on the cueing cells receive from surface. This may not be a problem in healthy patients, but may have an important role in medically-compromised-individuals in whom the composition of tissue-fluids is altered.

Negative bias of processing ambiguously cued emotional stimuli.

Daily we cope with upcoming potentially disadvantageous events. Therefore, it makes sense to be prepared for the worst case. Such a 'pessimistic' bias is reflected in brain activation during emotion processing. Healthy individuals underwent functional neuroimaging while viewing emotional stimuli that were earlier cued ambiguously or unambiguously concerning their emotional valence. Presentation of ambiguously announced pleasant pictures compared with unambiguously announced pleasant pictures resulted in increased activity in the ventrolateral prefrontal, premotor and temporal cortex, and in the caudate nucleus. This was not the case for the respective negative conditions. This indicates that pleasant stimuli after ambiguous cueing provided 'unexpected' emotional input, resulting in the adaptation of brain activity. It strengthens the hypothesis of a 'pessimistic' bias of brain activation toward ambiguous emotional events.

Rhesus monkeys know when they remember

Humans are consciously aware of some memories and can make verbal reports about these memories. Other memories cannot be brought to consciousness, even though they influence behavior. This conspicuous difference in access to memories is central in taxonomies of human memory systems but has been difficult to document in animal studies, suggesting that some forms of memory may be unique to humans. Here I show that rhesus macaque monkeys can report the presence or absence of memory. Although it is probably impossible to document subjective, conscious properties of memory in nonverbal animals, this result objectively demonstrates an important functional parallel with human conscious memory. Animals able to discern the presence and absence of memory should improve accuracy if allowed to decline memory tests when they have forgotten, and should decline tests most frequently when memory is attenuated experimentally. One of two monkeys examined unequivocally met these criteria under all test conditions, whereas the second monkey met them in all but one case. Probe tests were used to rule out “cueing” by a wide variety of environmental and behavioral stimuli, leaving detection of the absence of memory per se as the most likely mechanism underlying the monkeys' abilities to selectively decline memory tests when they had forgotten.

Covert attention accelerates the rate of visual information processing

Whenever we open our eyes, we are confronted with an overwhelming amount of visual information. Covert attention allows us to select visual information at a cued location, without eye movements, and to grant such information priority in processing. Covert attention can be voluntarily allocated, to a given location according to goals, or involuntarily allocated, in a reflexive manner, to a cue that appears suddenly in the visual field. Covert attention improves discriminability in a wide variety of visual tasks. An important unresolved issue is whether covert attention can also speed the rate at which information is processed. To address this issue, it is necessary to obtain conjoint measures of the effects of covert attention on discriminability and rate of information processing. We used the response-signal speed-accuracy tradeoff (SAT) procedure to derive measures of how cueing a target location affects speed and accuracy in a visual search task. Here, we show that covert attention not only improves discriminability but also accelerates the rate of information processing.

Visual attention to surfaces in three-dimensional space.

Although attention plays a significant role in vision, its spatial deployment and spread in the third dimension is not well understood. In visual search experiments we show that we cannot easily focus attention across isodepth loci unless they are part of a well-formed surface with locally coplanar elements. Yet we can easily spread our attention selectively across well-formed surfaces that span an extreme range of stereoscopic depths. In cueing experiments, we show that this spread of attention is, in part, obligatory. Attentional selectivity is reduced when targets and distractors are coplanar with or rest on a common receding stereoscopic plane. We conclude that attention cannot be efficiently allocated to arbitrary depths and extents in space but is linked to and spreads automatically across perceived surfaces.

Facilitating communication in children with multiple disabilities: three case studies of girls with Rett syndrome

Purpose: To investigate the effect of cueing on communicative responses of children with multiple disabilities in an educational setting. It was hypothesized that differences would exist in teacher interactional styles and the use of orienting cues would increase the communicative responses of the participants. Method: A naturalistic observation research method was employed in order to examine the interaction of three student-teacher dyads in three special schools. Three different activity types were videotaped from which interactions were coded and analysed. Results: Multi-modal cueing facilitated communicative responses of children with Rett syndrome. However, increased communication opportunities provided by caregivers did not elicit increased responses from the girls. Conclusion: There is a difference in cueing by teachers in their interactions with children with multiple disabilities. Also, more frequent communicative interactions did not necessarily lead to increased student responses. It is suggested that amount and type of cueing may need to be considered to be effective in generating student responses. The small number of participants, however, means findings should be viewed cautiously and that more research is indicated.

Prospective memory rehabilitation for adults with traumatic brain injury: A compensatory training programme

Primary objective: To describe a prospective memory rehabilitation programme based on a compensatory training approach and report the results of three case studies. Research design: Programme evaluation using pre-and post-intervention assessments and telephone follow-up. Methods and procedures: Three participants with traumatic brain injury completed 8 weeks of training with 1 - 2 hour individual sessions. Assessments were formal prospective memory assessment, self-report and measures of diary use. Experimental interventions: Intervention aimed to identify potential barriers, establish self-awareness of memory deficits, introduce a customized compensatory tool, a cueing system and organizational strategies. A significant other was involved in training to assist generalization. Main outcomes and results: All three participants improved on formal prospective memory assessment and demonstrated successful diary use after the programme. Self-report of prospective memory failure fluctuated and may reflect increased self-awareness. Conclusion: A compensatory approach may be useful in improving prospective memory performance following TBI.

Deficient inhibition of return in subclinical OCD only when attention is directed to the threatening aspects of a stimulus

Background - Inhibition of return (IOR) is thought to reflect inhibition of previously attended but irrelevant stimuli. Deficient IOR would increase the likelihood of revisiting previously searched locations or objects, thus leading to unproductive perseverations. Method - Therefore, using a novel IOR task, we investigated whether high scoring checkers attentional biases to threat would result in dysfunctional inhibitory functioning compared to low checkers. In two tasks, we compared 53 subclinical high and 49 low checkers regarding IOR effects for stimuli that were concordant with the concerns of high but not of low checkers (electrical kitchen appliances: e.g., toaster, kettle). The difference between the two tasks was the cueing procedure. In one task, an appliance was switched “ON” and “OFF” as an unpredictive cue, drawing attention to the functionality of the stimulus. Results - In this task, IOR was specifically attenuated in high checkers. In the other task, however, the cue was more abstract in form of a yellow outline that appeared around one of two appliances. Although the appliance was either “ON” or “OFF,” this did not seem to matter and high checkers revealed a typical IOR pattern similar to low checkers. Conclusions - We conclude that IOR mechanisms might not be generally deficient in high checkers; rather only when attention is drawn to the threatening aspects of ecologically valid stimuli, then disengagement of attention is deficient in high checkers. We make suggestions on how our task-specific findings may inform cognitive interventions that target attentional control in the treatment of checking/obsessive–compulsive disorder.

Observation of a finger or an object movement primes imitative responses differentially

Behavioural advantages for imitation of human movements over movements instructed by other visual stimuli are attributed to an ‘action observation-execution matching’ (AOEM) mechanism. Here, we demonstrate that priming/exogenous cueing with a videotaped finger movement stimulus (S1) produces specific congruency effects in reaction times (RTs) of imitative responses to a target movement (S2) at defined stimulus onset asynchronies (SOAs). When contrasted with a moving object at an SOA of 533 ms, only a human movement is capable of inducing an effect reminiscent of ‘inhibition of return’ (IOR), i.e. a significant advantage for imitation of a subsequent incongruent as compared to a congruent movement. When responses are primed by a finger movement at SOAs of 533 and 1,200 ms, inhibition of congruent or facilitation of incongruent responses, respectively, is stronger as compared to priming by a moving object. This pattern does not depend on whether S2 presents a finger movement or a moving object, thus effects cannot be attributed to visual similarity between S1 and S2. We propose that, whereas both priming by a finger movement and a moving object induces processes of spatial orienting, solely observation of a human movement activates AOEM. Thus, S1 immediately elicits an imitative response tendency. As an overt imitation of S1 is inadequate in the present setting, the response is inhibited which, in turn, modulates congruency effects.

Retrieval of implicit inhibitory processes:the impact of visual field, object-identity, and memory dynamics

After exogenously cueing attention to a peripheral location, the return of attention and response to the location can be inhibited. We demonstrate that these inhibitory mechanisms of attention can be associated with objects and can be automatically and implicitly retrieved over relatively long periods. Furthermore, we also show that when face stimuli are associated with inhibition, the effect is more robust for faces presented in the left visual field. This effect can be even more spatially specific, where most robust inhibition is obtained for faces presented in the upper as compared to the lower visual field. Finally, it is revealed that the inhibition is associated with an object’s identity, as inhibition moves with an object to a new location; and that the retrieved inhibition is only transiently present after retrieval.

Adults with dyslexia can use cues to orient and constrain attention but have a smaller and weaker attention spotlight

We report results from two experiments assessing distribution of attention and cue use in adults with dyslexia (AwD) and in a group of typically reading controls. Experiment 1 showed normal effects of cueing in AwD, with faster responses when probes were presented within a cued area and normal effects of eccentricity and stimulus onset asynchrony (SOA). In addition, AwD showed stronger benefits of a longer SOA when they had to move attention farther, and stronger effects of inclusion on the left, suggesting that cueing is particularly important in more difficult conditions. Experiment 2 tested the use of cues in a texture detection task involving a wider range of eccentricities and a shorter SOA. In this paradigm, focused attention at the central location is actually detrimental and cueing further reduces performance. Thus, if AwD have a more distributed attention, they should show a reduced performance drop at central locations and, if they do not use cues, they should show less negative effects of cueing. In contrast, AwD showed a larger drop and a positive effect of cueing. These results are better accounted for by a smaller and weaker spotlight of attention. Performance does not decrease at central locations because the attentional spotlight is already deployed with maximum intensity, which cannot be further enhanced at central locations. Instead, use of cueing helps to focus limited resources. Cues orient attention to the right area without enhancing it to the point where this is detrimental for texture detection. Implications for reading are discussed.

The effect of basketball sport aerobics on basketball skill development for fifth-grade students

The purpose of this study was to investigate the effectiveness of an experimental teaching method, Sport Aerobics, on the basketball skill acquisition of fifth grade students. This study investigated the differences in the shooting, dribbling, and passing scores of students taught with Sport Aerobics instruction compared to those taught with a traditional method, Practice Style. Sport Aerobics is an instructional method based on a theoretical framework developed by the researcher to enhance skill acquisition. This framework leads to teaching strategies such as using immediate feedback and specific cueing; arranging for students to engage in object free movement; arranging lessons, according to the framework's concept of movement progression, into lessons staged according to skill and sub-skill complexity; and instructing based on whole group organization. Sport Aerobic instructional strategies were designed to facilitate process learning that is recognized as important in today's development learning approach for age related curriculums. In contrast, the traditional Practice Style uses product-oriented strategies. ^ Four classrooms, consisting of seventy-nine fifth grade students from two physical education programs, at different locations, were randomly assigned to two treatments; Sport Aerobics and Practice Style for instruction over a 15 period curriculum. Using the American Alliance Physical Education Recreation & Dance tests, both groups were pretested and posttested for skill achievement of shooting, dribbling, and passing. Pretest and posttest skill score samples were collected and evaluated. ANCOVAs were performed on the posttests adjusted for the pretests to determine whether or not there would be greater achievement of skills with the Sport Aerobics method. Results failed to establish significant scoring differences between the two methods. Based on the literature and study findings a recommendation is made that longer lesson units will assist in the investigation of the effectiveness of both the instructional model and the individual elements that facilitate skill acquisition. ^