Examining the Spatiotemporal Disruption to Gaze When Using a Myoelectric Prosthetic Hand

The aim of this study was to provide a detailed account of the spatial and temporal disruptions to eye-hand coordination when using a prosthetic hand during a sequential fine motor skill. Twenty-one able-bodied participants performed 15 trials of the picking up coins task derived from the Southampton Hand Assessment Procedure with their anatomic hand and with a prosthesis simulator while wearing eye-tracking equipment. Gaze behavior results revealed that when using the prosthesis, performance detriments were accompanied by significantly greater hand-focused gaze and a significantly longer time to disengage gaze from manipulations to plan upcoming movements. The study findings highlight key metrics that distinguish disruptions to eye-hand coordination that may have implications for the training of prosthesis use.     

Memory rehabilitation for older adults: preserving independent living / Rehabilitación de la memoria para adultos mayores: preservación de la autonomía de vida

Abstract

Episodic memory problems are the hallmark of cognitive ageing in normal elderly people. Learning of new material is worse in pathological cognitive ageing, such as dementia and its preliminary states (mild cognitive impairment). Because episodic learning is crucial to preserve independent living in the elderly, rehabilitation programmes for everyday memory problems are welcomed. The scope of scientific interest has switched from treatment to prevention. We claim that lifestyle interventions are the most direct way to preserve cognition. We summarize evidence for changes in nutrition and exercise. In addition, psychological interventions for elderly people with normal or pathological cognitive ageing are available. Recent meta-analyses found lacking evidence of transfer to everyday life and long-term effects. We critically assess these meta-analyses. We propose theoretically derived experimental interventions relying on spared learning mechanisms. As an example we report visual-imagery training showing positive effects in a randomized control trial, using individual memory diaries on memory improvement.     

Is the centralization of potentially traumatic events always negative? An expansion of the Centrality of Events Scale

The autobiographical memory model of posttraumatic stress disorder (PTSD) argues that centralizing a traumatic event into one's life story is a maladaptive process associated with increased PTSD symptoms. Current measures of event centralization make no reference to whether individuals centralize the event in a positive or negative way. This study examined 400 undergraduate participants using a modified version of the Centrality of Events Scale composed of 2 factors measuring both positive and negative event centralization. Exploratory factor analysis confirmed the 2‐factor structure. Negative event centralization was associated with PTSD symptoms to a greater degree than was positive event centralization, and negative event centralization mediated the relationship between neuroticism and PTSD symptoms. Combined, these results suggest that the effect of event centralization is dependent on the valence with which the individual centralizes the event. The relationship shown between negative event centralization and PTSD symptoms supports the autobiographical memory model of PTSD.     

The effect of different distractions on remembering delayed intentions

In safety-critical domains, frequently intentions need to be delayed until an ongoing task is completed. Research using the delay-execute paradigm showed that interruptions during the delay cause forgetting. However, staff members often handle an initial distraction not by interrupting the ongoing task but by acknowledging the distraction or multitasking. In Experiments 1a and 1b, we observed that, compared to a no distraction condition, multitasking significantly decreased remembering of intentions and interrupting decreased remembering even further. In Experiment 2, interruptions with context change reduced remembering of intentions compared to uninterrupted delays, and at the same time, interruptions without context change improved memory performance compared to uninterrupted delays. However, improved memory performance resulted in decreased interrupting task performance. Theoretically, the results support the contextual cueing mechanism of delay-execute tasks. Considering safety-critical domains, multitasking, interruptions and context changes can contribute to forgetting of tasks.     

The animacy advantage for free-recall performance is not attributable to greater mental arousal

People often demonstrate better memory for animate concepts (e.g., lion and sailor) than for inanimate concepts (e.g., hammer and mountain). Researchers have attributed this effect to an adaptive memory mechanism that favours information relevant for survival, including information about living things. In the present experiment, we examined the hypothesis that people demonstrate better free-recall performance for animate than inanimate words because animate words tend to be associated with greater mental arousal than inanimate words, a factor that was not controlled for in previous experiments on this topic. To this end, we matched animate and inanimate word lists on mental arousal (and several other factors), and compared participants’ free-recall performance for the two word types. We were able to replicate past findings that participants’ free-recall of animate words exceeds their free-recall of inanimate words, but we found no support for the possibility that the effect stems from differences in mental arousal between animate and inanimate concepts, as this effect maintained even when the word lists were matched on mental arousal. The present results therefore indicate that mental arousal cannot explain the effects of animacy on free-recall performance.     

Temporal grouping effects in musical short-term memory

Recent theoretical accounts of verbal and visuo-spatial short-term memory (STM) have proposed the existence of domain-general mechanisms for the maintenance of serial order information. These accounts are based on the observation of similar behavioural effects across several modalities, such as temporal grouping effects. Across two experiments, the present study aimed at extending these findings, by exploring a STM modality that has received little interest so far, STM for musical information. Given its inherent rhythmic, temporal and serial organisation, the musical domain is of interest for investigating serial order STM processes such as temporal grouping. In Experiment 1, the data did not allow to determine the presence or the absence of temporal grouping effects. In Experiment 2, we observed that temporal grouping of tone sequences during encoding improves short-term recognition for serially presented probe tones. Furthermore, the serial position curves included micro-primacy and micro-recency effects, which are the hallmark characteristic of temporal grouping. Our results suggest that the encoding of serial order information in musical STM may be supported by temporal positional coding mechanisms similar to those reported in the verbal domain.     

Emotional distress and positive and negative memories from military deployment: the influence of PTSD symptoms and time

During military deployment, soldiers are confronted with both negative and positive events. What is remembered and how it affects an individual is influenced by not only the perceived emotion of the event, but also the emotional state of the individual. Here we examined the most negative and most positive deployment memories from a company of 337 soldiers who were deployed together to Afghanistan. We examined how the level of emotional distress of the soldiers and the valence of the memory were related to the emotional intensity, experience of reliving, rehearsal and coherence of the memories, and how the perceived impact of these memories changed over time. We found that soldiers with higher levels of post-traumatic stress disorder (PTSD) symptoms were more affected by both their negative and positive memories, compared with soldiers with lower levels of PTSD symptoms. Emotional intensity of the most negative memory increased over time in the group with highest levels of PTSD symptoms, but dropped in the other groups. The present study adds to the literature on emotion and autobiographical memory and how this relationship interacts with an individual’s present level of emotional distress and the passage of time.     

Who was that masked man? Conjoint representations of intrinsic motions with actor appearance

Motion plays an important role in recognising animate creatures. This research supports a distinction between intrinsic and extrinsic motions in their relationship to identifying information about the characters performing the motions. Participants viewed events involving costumed human characters. Intrinsic motions involved relative movements of a character’s body parts, whereas extrinsic motions involved movements with respect to external landmarks. Participants were later tested for recognition of the motions and who had performed them. The critical test items involved familiar characters performing motions that had previously been performed by other characters. Participants falsely recognised extrinsic conjunction items, in which characters followed the paths of other characters, more often than intrinsic conjunction items, in which characters moved in the manner of other characters. In contrast, participants falsely recognised new extrinsic motions less often than new intrinsic motions, suggesting that they remembered extrinsic motions but had difficulty remembering who had performed them. Modelling of receiver operating characteristics indicated that participants discriminated old items from intrinsic conjunction items via familiarity, consistent with conjoint representations of intrinsic motion and identity information. In contrast, participants used recollection to distinguish old items from extrinsic conjunction items, consistent with separate but associated representations of extrinsic motion and identity information.     

Do young adults show conceptual knowledge of previous distractors?

Using implicit tests, older adults have been found to retain conceptual knowledge of previously seen task-irrelevant information. While younger adults typically do not show the same effect, evidence from one study [Gopie, N., Craik, F. I. M., & Hasher, L. (2011). A double dissociation of implicit and explicit memory in younger and older adults. Psychological Science, 22, 634–640. doi:10.1177/0956797611403321] suggests otherwise. In that study, young adults showed greater explicit than implicit memory for previous distractors on a word fragment completion task. This was interpreted as evidence for maintaining access to previous conceptual knowledge of the distractors. Here, we report two failures to replicate that original finding, followed by a third study designed to test directly whether young adults use conceptual-level information that was previously irrelevant. Our findings agree with others that young adults show weak to no evidence of conceptual knowledge of previously irrelevant information.     

Activating attachment representations impact how we retrieve autobiographical memories

Although much research indicates that proximity to attachment figures confers many psychological benefits, there is little evidence pertaining to how attachment activation may impact autobiographical memory retrieval. Following a negative mood induction to elicit overgeneral autobiographical retrieval, participants (N?=?70) were administered an induction in which they imagined a person who is a strong attachment figure or an acquaintance. Participants then completed an autobiographical memory task to retrieve memories in response to neutral and negative cue words. Attachment priming resulted in less distress, increased retrieval of specific memories, and reduced retrieval of categoric memories. These findings indicate that activation of mental representations of attachment figures can impact on the specificity of autobiographical memory retrieval, and extends prevailing models of autobiographical memory by integrating them with attachment theory.