Short-term retention of proprioceptive information

The Joint Position Reproduction test (JPR), one of the most widely used measurements to estimate proprioceptive accuracy, requires the short term storage of proprioceptive information. It has been suggested that visuospatial sketchpad plays a fundamental role in the memorization of proprioceptive information. The current study aimed to investigate this assumption. To do so, we developed and used a novel JPR protocol to measure the retention capacity with respect to sequences of different positions. Our goal was to develop the original task further to make it comparable with other widely used short-term memory measurements, in which the memory capacity was determined by the number of the items participants retain (memory span). We compared participants’ (N=39) performance in this task to that of results of Corsi block-tapping task (capacity of the visuospatial sketchpad) and Digit span task (capacity of the phonological loop). Proprioceptive memory capacity did not correlate either with spatial or verbal memory capacity. The exploratory analysis revealed that proprioceptive span correlated positively with the performance if 5 joint positions had to be retained. Further associations with verbal span for 6 or 7 positions, and spatial span for 5 positions were found. Our findings do not support the idea that visuospatial sketchpad plays a fundamental role in the storage of proprioceptive information. The independence of span measures indicates that proprioceptive information might be stored in a subsystem independent of the visuospatial sketchpad or phonological loop.

Auditory and Visual Durations Load a Unitary Working-Memory Resource

Items in working memory are typically defined by various attributes, such as colour (for visual objects) and pitch (for auditory objects). The attribute of duration can be signalled by multiple modalities, but has received relatively little attention from a working-memory perspective. While the existence of specialist stores (e.g., the phonological loop and visuospatial sketchpad) is often asserted in the wider working-memory literature, the interval-timing literature has more often implied a unitary (amodal) store. Here we combine two modelling frameworks to probe the basis of working memory for duration; a Bayesian-observer framework, previously used to explain behaviour in duration-reproduction tasks, and mixture models, describing distributions of continuous reports about items in working memory. We modelled different storage mechanisms, such as a limited number of fixed-resolution slots or a resource spread between items at a cost to resolution, in order to ask whether items from different sensory modalities are maintained in separate, independent stores. We initially analysed data from 32 participants, who memorised between one and eight items before reproducing the duration of a randomly selected target. In separate blocks, items could be all visual, all auditory, or an alternating mixture of both. A small control experiment included a further condition with precuing of target modality. Certain kinds of slot models, resource models, and combination models incorporating both mechanisms could account for the data. However, looking across all plausible models, the decline in performance with increasing memory load was most consistent with a single store for event durations, regardless of stimulus modality.

The effects of information relevancy on driving behavior

Bus driving is a complex and cognitively challenging task that places high demands on bus drivers’ working memory. Increasing use of “In-Vehicle Information Systems” leads to driver distraction and is a contributing factor to many road accidents globally, and with systems for tickets, navigation, and timetables, bus drivers are more exposed to this additional workload than other actors in the traffic. This study provides insights into how bus drivers’ driving behavior is affected by auditory traffic information through a driving simulator study at the Swedish National Road and Transport Research Institute. A pre-study showed that many bus drivers in Gothenburg experience that a majority of the messages they receive are irrelevant to them. Difference in driving behavior was identified for conditions in which the drivers received messages irrelevant to their route, which might indicate that irrelevancy is an important factor for the workload imposed to the drivers. We hypothesize that irrelevant messages require processing in the visuospatial sketchpad, which might increase workload more than just auditory information processing. The results of this study implies that the routines for traffic communication between traffic controllers and bus drivers should be considerate, as to reduce the number of irrelevant messages that are cognitively loading the bus drivers.

Origami folding: Memory load effects on acquisition of sequential skills.

Cognitive and motor memory loads can affect sequential skills. Differentiating the execution and the acquisition of sequential skills, we studied the impact of cognitive or motoric dual-task loads on performance in Origami folding and changes with practice. Participants (N = 53) folded five Origami figures for four times each, which were randomly paired with five types of secondary tasks to cause either cognitive (verbal vs. visuospatial) or motoric (isochronous vs. nonisochronous tapping) memory load or none (control condition). Origami performance showed a typical learning curve from Repetition 1 to Repetition 4. We observed a dissociation between variants of dual-task load influencing Origami folding performance vs. the variants influencing learning (i.e. change in performance across the four repetitions). In particular, the learning of Origami folding was only interfered by the memory load of the cognitive visuospatial secondary task as well as by the isochronous tapping secondary task. This might be due to the use of visuospatial sketchpad and absolute timing mechanism during the acquisition of Origami folding. The performance of Origami folding was moderated by the isochronous tapping secondary task.

The Association Between Negative Attributional Style and Working Memory Performance

Introduction:It has been proposed that negative attributions contribute to impairment in cognitive task processing. However, it is still unknown whether negative attributions influence task processing in all cognitive tasks.Methods:To investigate this, 91 healthy participants completed attributional style questionnaire and performed three Working Memory (WM) tasks, which associated with different functions of WM (i.e. Central Executive System (CES) and visuospatial sketchpad).Results:The results demonstrated that negative attributions contribute to the impairment in cognitive tasks which is associated with spatial working memory rather than main central executive functions (i.e. switching and inhibition).Conclusions:It is concluded that negative attributions may selectively disrupt spatial working memory functions, thus a detrimental effect of negative attributions may be task specific.

Working Memory in Aphasia: Considering Discourse Processing and Treatment Implications

Evidence suggests that persons with aphasia (PWAs) present with working memory impairments that affect a variety of language tasks. Most of these studies have focused on the phonological loop component of working memory and little attention has been paid to the episodic buffer component. The episodic buffer, as a limited capacity, multimodal system that binds and integrates information from the phonological loop, visuospatial sketchpad, and long-term memory would likely be involved in discourse processing. The purposes of this article were to (1) review discourse level deficits associated with aphasia, (2) describe how a deficit at the level of the episodic buffer could cause such deficits, (3) to review discourse treatment approaches for PWAs, and (4) present preliminary results from a novel discourse treatment study for PWAs.