Relating numeric cognition and language processing: Do numbers and words share a common representational platform?

Numerical processing and language processing are both grounded in space. In the present study we investigated whether these are fully independent phenomena, or whether they share a common basis. If number processing activates spatial dimensions that are also relevant for understanding words, then we can expect that processing numbers may influence subsequent lexical access to words. Specifically, if high numbers relate to upper space, then they can be expected to facilitate understanding of words such as bird that are having referents typically found in the upper vertical space. The opposite should hold for low numbers. These should facilitate the understanding of words such as ground referring to entities with referents in the lower vertical space. Indeed, in two experiments we found evidence for such an interaction between number and word processing. By eliminating a contribution of linguistic factors gained from additional investigations on large text corpora, this strongly suggests that understanding numbers and language is based on similar modal representations in the brain. The implications of these findings for a broader perspective on grounded cognition will be discussed.     

To think or not to think,that is the question: Individual differences in suppression and rebound effects in autobiographical memory

Two studies explored the effects of forget instructions on autobiographical memory at immediate test and following delays of either 12–13 months, or 3–4 months. Using the Autobiographical Think/No-Think procedure (cf., Noreen & MacLeod, 2013), 24 never-depressed participants (Study 1) first generated 12 positive and 12 negative autobiographical memories and associated cues. Participants were then asked to recall the memory associated with some of the cues (i.e., ‘think’ condition), or to avoid saying or thinking about the memory associated with other cues (i.e., ‘no-think’ condition). Participants were then asked to recall the memories associated with all the cues at immediate test and following a delay of 12–13 months. Participants were found to be successful at forgetting both positive and negative autobiographical memories following ‘no-think’ instructions at immediate test but this forgetting effect did not persist following a 12–13 month delay. This pattern of remembering and forgetting was replicated in a second study (using 27 never-depressed participants) following a 3–4 month delay. Participants who had been less successful at forgetting ‘no-think’ memories at immediate test, were more likely to show rebound effects for those memories following a delay compared to memories which received neither ‘think’ nor ‘no-think’ instructions. Individual differences in inhibitory control and the efficacy of potential therapeutic interventions of ‘no-think’ instructions are considered.     

Discrimination of two neighboring intra- and intermodal empty time intervals marked by three successive stimuli

We investigated the discrimination of two neighboring intra- or inter-modal empty time intervals marked by three successive stimuli. Each of the three markers was a flash (visual—V) or a sound (auditory—A). The first and last markers were of the same modality, while the second one was either A or V, resulting in four conditions: VVV, VAV, AVA and AAA. Participants judged whether the second interval, whose duration was systematically varied, was shorter or longer than the 500-ms first interval. Compared with VVV and AAA, discrimination was impaired with VAV, but not so much with AVA (in Experiment 1). Whereas VAV and AVA consisted of the same set of single intermodal intervals (VA and AV), discrimination was impaired in the VAV compared to the AVA condition. This difference between VAV and AVA could not be attributed to the participants' strategy to perform the discrimination task, e.g., ignoring the standard interval or replacing the visual stimuli with sounds in their mind (in Experiment 2). These results are discussed in terms of sequential grouping according to sensory similarity.     

Sequential aiming with one and two limbs: Effects of target size

It is well reported that movement times to the first target in a two-target sequence are slower than when a single target response is required. This one-target advantage has been shown to emerge when the two-target sequence is performed with the same limb and when the first and second segments within the sequence are performed with different limbs (i.e., when there is a switch between limbs at the first target). The present study examined the functional dependency between response segments in both single and two limb sequential aiming by varying the accuracy demands at the first and second target. Results revealed that, for both one and two limb conditions, the one-target advantage was present with large first targets but not with small first targets. Additionally, when the first target was large and the second target was small, spatial variability at the first target was significantly less (or constrained more) in both one and two limb conditions compared to conditions requiring only a single target response. These findings suggest that similar principles underlie the one-target advantage in both single and two limb sequential movements.     

Intentional Binding is independent of the validity of the action effect's identity

When an action produces an effect, both events are perceived to be shifted in time toward each other. This shift is called Intentional Binding (IB) effect. First evidence shows that this shift does not depend on the statistical predictability of the produced effect's identity (Desantis, Hughes, & Waszak, 2012). We confirm this result by comparing the perceived duration of action–effect intervals before valid and invalid action effects using the method of constant stimuli. The perceived duration of action–effect intervals did not differ for valid and invalid effects. This result was true for different durations of the action–effect interval (Experiments 1–4: 250 ms, Experiments 1 & 2: 400 ms), different effect modalities (Experiments 1 & 3: visual, Experiments 2–4: auditive), and two types of validity variations (Experiments 1 & 2: 80% valid, Experiments 3 & 4: 100% valid vs. random). We validated our results by using a clock paradigm and a numerical duration estimation task (Experiment 4). We conclude that the IB effect is not the result of internal prediction due to action–effect bindings, but might rely on higher-order processes.     

The influences of tropical climate on imagined walking time

This study investigated the effects of a Tropical Climate (TC) on actual and imagined walking times. Participants had to execute and imagine walking 3 distances with or without a 10-kg weight in either a TC or an Air Conditioning (AC) condition. The motor imagery quality was evaluated by computing the isochrony index. The results revealed that movement times were shorter for imagined walking than for actual walking and increased with the distance of the paths in both cases. By contrast, the effect of the load increased actual walking times for the 10- and 15-meter distances without affecting imagined walking times. Importantly, the isochrony index was negatively affected by the increase in load and distance and the effects of distance were amplified in a TC. These findings showed that the environmental climate in which motor imagery arises can modulate the subject’s ability to build up the temporal characteristics of simulated actions.     

An analysis of factors affecting wrong-way driving at a highway entrance using a driving simulator among older drivers with cognitive decline

About 200 highway wrong-way driving cases occur annually in Japan, of which about 70% are caused by older drivers. The number of these cases has remained consistent despite adoption of full-fledged measures against wrong-way driving, thus demonstrating the need for further measures. Reports indicate that older drivers include those with cognitive decline. Moreover, it has been revealed that drivers over 75 years of age who caused wrong-way driving had lower test scores in the usual cognitive function tests performed at the time of licence renewal. However, there is no clear evidence on the relationship between cognitive decline and driving behaviour that stimulates wrong-way driving. In this paper, we reproduced a wrong-way driving approaching a right turn to an expressway exit in a virtual environment using a driving simulator for older drivers, including those with mild cognitive impairment (MCI). In addition to the measurement of driving behaviour and eye-tracking during simulator driving, we conducted a cognitive function test to investigate the relationship between driving behaviour and visual behaviour factors that initiate reverse running and cognitive decline. The results revealed that the reason for the start of a highway wrong-way driving may be a human error at the recognition stage of overlooking a visual wrong-way driving countermeasure, or a human error at the judgement stage of failing to suppress action despite noticing the visual countermeasure. Additionally, attentional and executive functions were related to the wrong-way initiative, although MCI did not affect it. This suggests that those who could not control their wrong-way driving behaviour despite observing the signs had specific executive function deficits.     

Necessary condition for forward progression in ballistic walking

Ballistic walking requires an appropriate configuration of posture and velocity at toe-off to avoid backward falling. In this study, we investigated a determinant of the state of the body center of mass (COM) at the toe-off with regard to ballistic walking. We used an inverted pendulum model to represent ballistic trajectories and the necessary condition for forward progression by a simple relationship between the COM states (position and velocity) at toe-off. This condition was validated through a computer simulation of a 7-link musculoskeletal model and measurement experiments of human movements involving stepping and walking. The results of the model simulation were in good agreement with some of the results predicted by the inverted pendulum model. The measurement experiments of walking and stepping movements showed that most COM states at toe-off satisfied the condition for forward progression and the measured trajectories during single support phase were similar to the ballistic trajectories although humans are capable of walking in non-ballistic ways. These results suggested that the necessary condition for forward progression can predict the COM states at toe-off for efficient movement and for avoiding backward falling during single support phase.     

Building Opportunity: Developing City Systems to Expand and Improve After School Programs

A growing body of research is examining the strengths and weaknesses of specific after school programs and their effect on youth outcomes. Few reviews, however, have sought to examine the components of citywide system-building—to understand intentional efforts to develop, support and sustain high quality after school programming across a community. Beginning in the mid-1990s and continuing through the present, private funders, public officials and program practitioners in cities across America have joined together to build systems to support the expansion and improvement of after school programs at the city-level. This paper presents the community context and underlying principles that drove the development of Baltimore’s After-School Strategy; articulates a set of system components derived from this experience and the available literature; and lays out future work to expand high quality after-school opportunities for youth in Baltimore and in other distressed urban environments.     

Learning the form of causal relationships using hierarchical bayesian models

People learn quickly when reasoning about causal relationships, making inferences from limited data and avoiding spurious inferences. Efficient learning depends on abstract knowledge, which is often domain or context specific, and much of it must be learned. While such knowledge effects are well documented, little is known about exactly how we acquire knowledge that constrains learning. This work focuses on knowledge of the functional form of causal relationships; there are many kinds of relationships that can apply between causes and their effects, and knowledge of the form such a relationship takes is important in order to quickly identify the real causes of an observed effect. We developed a hierarchical Bayesian model of the acquisition of knowledge of the functional form of causal relationships and tested it in five experimental studies, considering disjunctive and conjunctive relationships, failure rates, and cross-domain effects. The Bayesian model accurately predicted human judgments and outperformed several alternative models.