Factors which influence the difficulty of the spatial path in Corsi's block-tapping test

Path Configuration Complexity Affects Spatial Memory Span on the eCorsi Task but Does Not Influence Performance of a Concurrent Auditory Discrimination Task

Visuospatial working memory is often assessed using the Corsi block-tapping task where set size is used to estimate capacity. It is well established that characteristics of the Corsi task path configuration such as length, crossings, and angles influence recall accuracy suggesting that more complex path configurations increase the load on working memory. However, the interaction between set size and path configuration is not well understood. Here we used a secondary auditory task to probe if set size and path configuration impose a similar type of load on the system. Nineteen participants (age = 25.3 ± 3.9 years) performed a computerized version of the Corsi test either alone (single) or simultaneously with an auditory tone discrimination task (dual). The eCorsi task involved a set of simple (no crosses, shorter lengths, larger angles) or complex (>2 crosses, longer lengths, smaller angles) paths at set sizes of five to eight blocks. Results showed significantly lower recall accuracy for the complex compared to the simple paths (63.32% vs. 86.38%, p < 0.001) at all set sizes, regardless of task condition (single, dual). Auditory performance (accuracy and response time) was significantly lower in the dual compared to single task (85.34% vs. 99.67%, p < 0.001), but performance was not affected by the complexity of the eCorsi path configuration. These findings suggest that set size and path complexity impose a different type of load on the working memory system and may rely on different resources.

On-item fixations during serial encoding do not affect spatial working memory

Ample evidence suggests that there is overlap between the eye-movement system and spatial working memory. Such overlapping structures or capacities may result in interference on the one hand and beneficial support on the other. We investigated eye-movement control during encoding of verbal or spatial information, keeping the display the same between tasks. Saccades to to-be-encoded items were scarce during spatial encoding in comparison with verbal encoding. However, despite replicating this difference across different tasks (serial, free recall) and presentation modalities (simultaneous, sequential presentation), we found no relation between item fixations and memory performance-that is, no costs or benefits. Inducing a change from covert to overt encoding did not affect spatial memory performance as well. In contrast, regressive fixations on prior items, that were no longer on the screen, were associated with increased spatial memory performance. Regressions occurred mainly at the end of the encoding period and were targeted at the first presented item. Our results suggest a dissociation between two types of fixations that accompany serial spatial memory: On-item fixations are epiphenomenal; regressions indicate rehearsal or output preparation.

On the Right Track? Investigating the Effect of Path Characteristics on Visuospatial Bootstrapping in Verbal Serial Recall

Visuospatial bootstrapping (VSB) occurs when memory for verbal material is enhanced via association with meaningful visuospatial information. Sequences of digits are visually presented either in the center of the screen or within a keypad layout in which the digits may be arranged identically to familiar pin pad and mobile phone layouts, or randomly. Recall is consistently higher when digits are presented in the familiar layout. This “bootstrapping” could involve primarily long-term knowledge of the layout, primarily short-term memory of the unique spatial path, or may depend on both. We manipulated the path complexity of sequences to test whether the VSB effect depends on the quality of spatial representations in conjunction with the familiarity of the spatial layout in two experiments. We consistently observed both VSB effects and path complexity effects on verbal serial recall, but never observed any interaction between these factors, even when articulatory suppression was imposed. Analysis of recall by serial position revealed that the VSB effect was focused on the end-of-list items. Our finding of pervasive path complexity effects on verbal serial recall suggests incidental encoding of spatial path occurs during visually-presented verbal tasks regardless of layout familiarity, confirming that spatial factors can affect verbal recall, but ruling out the notion that incidental spatial paths are uniquely and voluntarily encoded with familiar layouts.

Did I see your hand moving? The effect of movement-related information on the Corsi block tapping task

The Corsi Block Tapping Task is a widespread test used to assess spatial working memory. Previous research hypothesized that the discrepancy found in some cases between the traditional and the digital (touchscreen) version of the Corsi block tapping task may be due to a direct motor resonance between the experimenter's and the participant's hand movements. However, we hypothesize that this discrepancy might be due to extra movement-related information included in the traditional version, lacking in the digital one. We investigated the effects of such task-irrelevant information using eCorsi, a touchscreen version of the task. In Experiment 1, we manipulate timing in sequence presentation, creating three conditions. In the Congruent condition, the inter-stimulus intervals reflected the physical distance in which the stimuli were spatially placed: The longer the spatial distance, the longer the temporal interval. In the Incongruent condition the timing changed randomly. Finally, in the Isochronous condition every stimulus appeared after a fixed interval, independently from its spatial position. The results showed a performance enhancement in the Congruent condition, suggesting an incidental spatio-temporal binding. In Experiment 2, we added straight lines between each location in the sequences: In the Trajectories condition participants saw trajectories from one spatial position to the other during sequence presentation, while a condition without such trajectories served as control. Results showed better performances in the Trajectories condition. We suggest that the timing and trajectories information play a significant role in the discrepancies found between the traditional and the touchscreen version of the Corsi Block Tapping Task, without the necessity of explanations involving direct motor resonance (e.g. seeing an actual hand moving) as a causal factor.

Spatio-Temporal Structure, Path Characteristics, and Perceptual Grouping in Immediate Serial Spatial Recall

Immediate serial spatial recall measures the ability to retain sequences of locations in short-term memory and is considered the spatial equivalent of digit span. It is tested by requiring participants to reproduce sequences of movements performed by an experimenter or displayed on a monitor. Different organizational factors dramatically affect serial spatial recall but they are often confounded or underspecified. Untangling them is crucial for the characterization of working-memory models and for establishing the contribution of structure and memory capacity to spatial span. We report five experiments assessing the relative role and independence of factors that have been reported in the literature. Experiment 1 disentangled the effects of spatial clustering and path-length by manipulating the distance of items displayed on a touchscreen monitor. Long-path sequences segregated by spatial clusters were compared with short-path sequences not segregated by clusters. Recall was more accurate for sequences segregated by clusters independently from path-length. Experiment 2 featured conditions where temporal pauses were introduced between or within cluster boundaries during the presentation of sequences with the same paths. Thus, the temporal structure of the sequences was either consistent or inconsistent with a hierarchical representation based on segmentation by spatial clusters but the effect of structure could not be confounded with effects of path-characteristics. Pauses at cluster boundaries yielded more accurate recall, as predicted by a hierarchical model. In Experiment 3, the systematic manipulation of sequence structure, path-length, and presence of path-crossings of sequences showed that structure explained most of the variance, followed by the presence/absence of path-crossings, and path-length. Experiments 4 and 5 replicated the results of the previous experiments in immersive virtual reality navigation tasks where the viewpoint of the observer changed dynamically during encoding and recall. This suggested that the effects of structure in spatial span are not dependent on perceptual grouping processes induced by the aerial view of the stimulus array typically afforded by spatial recall tasks. These results demonstrate the independence of coding strategies based on structure from effects of path characteristics and perceptual grouping in immediate serial spatial recall.

Corsi's Block-Tapping Test: Some Characteristics of the Spatial Path Which Influence Memory

By using a sequence of digits it is possible to indicate the path of Corsi's block-tapping test by drawing a line to join the central points of the cubes which make up the sequence. By doing this one can analyze the sequence of digits according to quantitative parameters. There were three characteristics of the spatial path taken into consideration in this research: the number of cubes which constitute a series of digits, the number of times the path intersected itself, and the length of the path measured in millimeters. The experiment, carried out with 70 university students, showed that all three factors were significant on analysis of variance, and also that there were differences between the sexes, the men performing better. No interactions were significant. Despite this, additional significant differences were found among the series with the same number of cubes, intersections, and length, meaning that other variables influence the difficulty of the spatial path.

Computerization of the standard corsi block-tapping task affects its underlying cognitive concepts: a pilot study

The tablet computer initiates an important step toward computerized administration of neuropsychological tests. Because of its lack of standardization, the Corsi Block-Tapping Task could benefit from advantages inherent to computerization. This task, which requires reproduction of a sequence of movements by tapping blocks as demonstrated by an examiner, is widely used as a representative of visuospatial attention and working memory. The aim was to validate a computerized version of the Corsi Task (e-Corsi) by comparing recall accuracy to that on the standard task. Forty university students (Mage = 22.9 years, SD = 2.7 years; 20 female) performed the standard Corsi Task and the e-Corsi on an iPad 3. Results showed higher accuracy in forward reproduction on the standard Corsi compared with the e-Corsi, whereas backward performance was comparable. These divergent performance patterns on the 2 versions (small-to-medium effect sizes) are explained as a result of motor priming and interference effects. This finding implies that computerization has serious consequences for the cognitive concepts that the Corsi Task is assumed to assess. Hence, whereas the e-Corsi was shown to be useful with respect to administration and registration, these findings also stress the need for reconsideration of the underlying theoretical concepts of this task.

Memória visuoespacial e cinestésica de curto prazo em crianças de 7 a 10 anos

Nós investigamos a memória visuoespacial e cinestésica de curto prazo em crianças entre 7 e 10 anos utilizando a tarefa de Blocos de Corsi. O desempenho melhora com a idade, é afetado pela extensão das séries e pelo número de cruzamentos. O desempenho é melhor na modalidade visual do que na cinestésica; ambas as modalidades são afetadas da mesma forma pela extensão e pelo número de cruzamentos. As curvas de posição serial apresentam forte efeito de primazia; o efeito de recência está presente apenas na modalidade visual. Nas séries com seis e sete blocos, quando considerado o número de cruzamentos, o desempenho tende a melhorar numa taxa mais elevada para a modalidade visual do que para cinestésica. Os resultados não permitem supor um sistema de memória cinestésico independente do espacial, mas sugere que ambos contribuem para o desempenho na tarefa de Corsi.

Corsi Block-Tapping task performance as a function of path configuration

The Corsi Block-Tapping (CB) task has been used as a measure of spatial memory since its development in 1971. However, a standard set of items has been developed for this task, and inconsistencies in performances within levels have been demonstrated in association with different path configuration. This study investigated item consistency by analyzing the performances of 94 young adult participants on a block-tapping task that involved five quasi-randomly determined sequences at each of nice levels of difficulty. In general, performance declined with increasing path length. Cochran Q-test comparisons were conducted on the items within each level, and differential performance were identified at levels 7 and 8 only. Pairwise comparisons determined the specific items for which performance was discrepant, and further analysis indicated that performance decrement were related to more complicated block-tapping paths. The findings suggest that this version of the CB task is relatively consistent overall, and the observed effect of path configuration indirectly corroborated the spatial nature of this task. Performance heterogeneity at higher levels reflected more complicated path configuration and, presumably, greater span capacity load. Differential intra-level item consistency should be considered in clinical applications of spatial (configural) memory tasks in order to avoid erroneous interpretations concerning sustained attention ability based on failures within levels.