Motor and visual codes interact to facilitate visuospatial memory performance

Negative Effects of Embodiment in a Visuo-Spatial Working Memory Task in Children, Young Adults, and Older Adults

Studies examining the effect of embodied cognition have shown that linking one's body movements to a cognitive task can enhance performance. The current study investigated whether concurrent walking while encoding or recalling spatial information improves working memory performance, and whether 10-year-old children, young adults, or older adults (M age = 72 years) are affected differently by embodiment. The goal of the Spatial Memory Task was to encode and recall sequences of increasing length by reproducing positions of target fields in the correct order. The nine targets were positioned in a random configuration on a large square carpet (2.5 m × 2.5 m). During encoding and recall, participants either did not move, or they walked into the target fields. In a within-subjects design, all possible combinations of encoding and recall conditions were tested in counterbalanced order. Contrary to our predictions, moving particularly impaired encoding, but also recall. These negative effects were present in all age groups, but older adults' memory was hampered even more strongly by walking during encoding and recall. Our results indicate that embodiment may not help people to memorize spatial information, but can create a dual-task situation instead.

Effects of pointing movements on visuospatial working memory in a joint-action condition: Evidence from eye movements

Previous studies showed that (a) performing pointing movements towards to-be-remembered locations enhanced their later recognition, and (b) in a joint-action condition, experimenter-performed pointing movements benefited memory to the same extent as self-performed movements. The present study replicated these findings and additionally recorded participants’ fixations towards studied arrays. Each trial involved the presentation of two consecutive spatial arrays, where each item occupied a different spatial location. The item locations of one array were encoded by mere visual observation (the no-move array), whereas the locations of the other array were encoded by observation plus pointing movements (the move array). Critically, in Experiment 1, participants took turns with the experimenter in pointing towards the move arrays (joint-action condition), while in Experiment 2 pointing was performed only by the experimenter (passive condition). The results showed that the locations of move arrays were recognized better than the locations of no-move arrays in Experiment 1, but not in Experiment 2. The pattern of eye-fixations was in line with behavioral findings, indicating that in Experiment 1, fixations to the locations of move arrays were higher in number and longer in duration than fixations to the locations of no-move arrays, irrespective of the agent who performed the movements. In contrast, no differences emerged in Experiment 2. We propose that, in the joint-action condition, self- and other-performed pointing movements are coded at the same representational level and their functional equivalency is reflected in a similar pattern of eye-fixations.

It's a matter of (executive) load: Separation as a load-dependent resetting procedure

Lee and Schwarz made considerable theoretical advances in the psychology of cleansing by proposing that cleaning actions might serve as separation procedures between two psychological entities. Here, we propose that the effectiveness of the separation process may be modulated by the available amount of executive resources, and that separation may operate as a load-dependent resetting procedure.

Integration of Eye-Centered and Landmark-Centered Codes in Frontal Eye Field Gaze Responses

The visual system is thought to separate egocentric and allocentric representations, but behavioral experiments show that these codes are optimally integrated to influence goal-directed movements. To test if frontal cortex participates in this integration, we recorded primate frontal eye field activity during a cue-conflict memory delay saccade task. To dissociate egocentric and allocentric coordinates, we surreptitiously shifted a visual landmark during the delay period, causing saccades to deviate by 37% in the same direction. To assess the cellular mechanisms, we fit neural response fields against an egocentric (eye-centered target-to-gaze) continuum, and an allocentric shift (eye-to-landmark-centered) continuum. Initial visual responses best-fit target position. Motor responses (after the landmark shift) predicted future gaze position but embedded within the motor code was a 29% shift toward allocentric coordinates. This shift appeared transiently in memory-related visuomotor activity, and then reappeared in motor activity before saccades. Notably, fits along the egocentric and allocentric shift continua were initially independent, but became correlated across neurons just before the motor burst. Overall, these results implicate frontal cortex in the integration of egocentric and allocentric visual information for goal-directed action, and demonstrate the cell-specific, temporal progression of signal multiplexing for this process in the gaze system.

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.

Pointing movements and visuo-spatial working memory in a joint setting: the role of motor inhibition

Previous studies have shown that, under specific conditions, arrays that have been pointed at encoding are recognized better than passively viewed ones. According to one interpretation, the superior recognition of pointed-to arrays can be explained by the motor inhibition of passively viewed arrays. The present study sought to determine whether a similar motor inhibition can be induced also when the participants observed a co-actor perform the pointing movements. Participants were presented with two spatial arrays, one of which was encoded via observation only (the no-move array), while the other was encoded with pointing movements (the move array); movements were performed either by the participant or by the experimenter. Experiment 1 replicated the advantage of self-pointed arrays over passively viewed arrays. Experiment 2 showed that, when participants passively observed the pointing movements performed by the experimenter, move arrays were recognized no better than no-move arrays. Finally, Experiment 3 demonstrated that, in a joint-action condition in which participants alternated with the experimenter in making pointing movements, the advantage of experimenter-pointed arrays over passively viewed arrays was significant and similar in size to the advantage produced by self-performed movements. Importantly, a series of cross-experiment comparisons indicated that the higher recognition of both self- and experimenter-pointed arrays in Experiment 3 could be explained by the motor inhibition of no-move arrays. We propose that, in a joint condition, the pointing movements performed by the experimenter were represented in the same functional way as self-performed movements and that this produced the motor inhibition of passively viewed arrays.

Motivated Cognition: Effects of Reward, Emotion, and Other Motivational Factors Across a Variety of Cognitive Domains

A growing body of literature has demonstrated that motivation influences cognitive processing. The breadth of these effects is extensive and span influences of reward, emotion, and other motivational processes across all cognitive domains. As examples, this scope includes studies of emotional memory, value-based attentional capture, emotion effects on semantic processing, reward-related biases in decision making, and the role of approach/avoidance motivation on cognitive scope. Additionally, other less common forms of motivation–cognition interactions, such as self-referential and motoric processing can also be considered instances of motivated cognition. Here I outline some of the evidence indicating the generality and pervasiveness of these motivation influences on cognition, and introduce the associated ‘research nexus’ at Collabra: Psychology.

Pointing movements both impair and improve visuospatial working memory depending on serial position

Two experiments investigated the effects of pointing movements on the item and order recall of random, horizontal, and vertical arrays consisting of 6 and 7 squares (Experiment 1) or 8 and 9 squares (Experiment 2). In the encoding phase, participants either viewed the items passively (passive-view condition) or pointed towards them (pointing condition). Then, after a brief interval, they were requested to recall the locations of the studied squares in the correct order of presentation. The critical result was that, for all types of arrays, the effects of the encoding condition varied as a function of serial position: for the initial and central positions accuracy was higher in the passive-view than in the pointing condition (confirming the standard inhibitory effect of pointing movements on visuospatial working memory), whereas the reverse pattern occurred in the final positions-showing a significant advantage of the pointing condition over the passive-view condition. Findings are interpreted as showing that pointing can have two simultaneous effects on the recall of spatial locations, a positive one due to the addition of a motor code and a negative one due to the attentional requirements of hand movements, with the net impact on serial recall depending on the amount of attention resources needed for the encoding of each position. Implications for the item-order hypothesis and the perceptual-gestural account of working memory are also discussed.

The effects of task-relevant saccadic eye movements performed during the encoding of a serial sequence on visuospatial memory performance

Visuospatial working memory (VSWM) is a set of cognitive processes used to encode, maintain and manipulate spatial information. One important feature of VSWM is that it has a limited capacity such that only few items can be actively stored and manipulated simultaneously. Given the limited capacity, it is important to determine the conditions that affect memory performance as this will improve our understanding of the architecture and function of VSWM. Previous studies have shown that VSWM is disrupted when task-irrelevant eye movements are performed during the maintenance phase; however, relatively fewer studies examined the role of eye movements performed during the encoding phase. On one hand, performing eye movements during the encoding phase could result in a stronger memory trace because the memory formation is reinforced by the activation of the motor system. On the other hand, performing eye movements to each target could disrupt the configural processing of the spatial array because the spatial representation has to be updated with each movement to maintain perceptual stability. Therefore, this work was conducted to examine whether task-relevant saccadic eye movements performed during the encoding phase of a visuospatial working memory task affect the recall of serially presented targets. Results from two experiments showed that average recall accuracy was significantly higher when the spatial array (set size ≥ 7) was encoded using a covert strategy-that is, while participants fixated on a central target, in comparison to an overt strategy-that is, while participants moved their eyes to fixate on each target. Furthermore, the improvement in accuracy was evident only for targets presented in the first half of the sequence, suggesting that the primacy effect is modulated by the presence of eye movements. We propose that executing saccades during encoding could interfere with the ability to use a chunking strategy or disrupt active visualization of the configuration. In conclusion, this is the first study to show that task-relevant saccadic eye movements performed during encoding may actually reduce the spatial span of VSWM. These results extend the current knowledge about the role of eye movements in VSWM, and have implications for future studies investigating the VSWM.

Compensatory effects of pointing and predictive cueing on age-related declines in visuospatial working memory

In this study, we investigated whether the visuospatial working memory performance of young and older adults would improve if they used a multimodal as compared with a unimodal encoding strategy, and whether or not visual cues would add to this effect. In Experiment 1, participants were presented with trials consisting of an array of squares and an array of circles. They were instructed to point at one type of figure (multimodal encoding strategy) and only to observe the other (unimodal encoding strategy). After each trial, an immediate location recognition test of one of the two arrays followed. In Experiment 2, the same task was used, but a cue was provided, either before or after the encoding phase, indicating which of the two arrays would be tested. Our results showed that a multimodal, as compared with a unimodal, encoding strategy improved visuospatial working memory performance in both young and older adults (Exp. 1), and that adding visual cues to the multimodal but not to the unimodal encoding strategy improved older adults' performance up to the level of young adults (Exp. 2). In both age groups, cueing after encoding led to higher performance in the multimodal than in the unimodal condition when the second array was tested. However, cueing before encoding led to higher performance in the multimodal than in the unimodal condition when the first array of the figure sequence was tested. These results suggest that pointing together with predictive cueing can have beneficial effects on visuospatial working memory, which is especially important for older adults.

Effects of pointing compared with naming and observing during encoding on item and source memory in young and older adults

Research showed that source memory functioning declines with ageing. Evidence suggests that encoding visual stimuli with manual pointing in addition to visual observation can have a positive effect on spatial memory compared with visual observation only. The present study investigated whether pointing at picture locations during encoding would lead to better spatial source memory than naming (Experiment 1) and visual observation only (Experiment 2) in young and older adults. Experiment 3 investigated whether response modality during the test phase would influence spatial source memory performance. Experiments 1 and 2 supported the hypothesis that pointing during encoding led to better source memory for picture locations than naming or observation only. Young adults outperformed older adults on the source memory but not the item memory task in both Experiments 1 and 2. In Experiments 1 and 2, participants manually responded in the test phase. Experiment 3 showed that if participants had to verbally respond in the test phase, the positive effect of pointing compared with naming during encoding disappeared. The results suggest that pointing at picture locations during encoding can enhance spatial source memory in both young and older adults, but only if the response modality is congruent in the test phase.

Examining the influence of action on spatial working memory: the importance of selection

We report three experiments that examine the influence of pointing-to relative to passively viewing an array of objects that participants are attempting to memorize. Recently, Chum, Bekkering, Dodd, and Pratt (2007) provided evidence that pointing to objects enhanced memory relative to passively viewing objects when pointing instruction was manipulated within trial (e.g., point to one array but passively view the other). We replicate this result but also demonstrate that when pointing instruction is blocked (e.g., participants point to or passively view all items in an array as opposed to pointing to some while passively viewing others), pointing to an array of objects actually decreases memory relative to passively viewing that array. Moreover, when pointing is manipulated within trial, the influence of action on working-memory performance appears to be attributable to an enhancement of processing of the pointed-to items as well as a subsequent inhibition of the passively viewed array. These results demonstrate that while action can enhance working memory under conditions where a subset of items is actively selected for additional processing, when selection is not a requirement (e.g., either point to everything or passively view everything), action decreases working-memory performance. Thus, the relationship between action and spatial working memory is complex and context dependent. These results are also discussed as they relate to other similar phenomena (e.g., retrieval-induced forgetting, Corsi Blocks test) in which selection during processing may be critical, and collectively these results provide important insight into spatial working memory and the factors that influence it.