Following Instructions in Patients With Schizophrenia: The Benefits of Actions at Encoding and Recall

Exploring techniques for encoding spoken instructions in working memory: a comparison of verbal rehearsal, motor imagery, self-enactment and action observation

Encoding and recalling spoken instructions is subject to working memory capacity limits. Previous research suggests action-based encoding facilitates instruction recall, but has not directly compared benefits across different types of action-based techniques. The current study addressed this in two experiments with young adults. In Experiment 1, participants listened to instructional sequences containing four action-object pairs, and encoded these instructions using either a motor imagery or verbal rehearsal technique, followed by recall via oral repetition or enactment. Memory for instructions was better when participants used a motor imagery technique during encoding, and when recalling the instructions by enactment. The advantage of using a motor imagery technique was present in both verbal and enacted recall. In Experiment 2, participants encoded spoken instructions whilst implementing one of four techniques (verbal rehearsal, motor imagery, observation of others' actions or self-enactment), and then recalled the instructions by oral repetition or enactment. For both verbal and enacted recall, memory for instructions was least accurate in the rehearsal condition, while the other encoding conditions did not differ from each other. These novel findings indicate similar benefits of imagining, observation and execution of actions in encoding spoken instructions, and enrich current understanding of action-based benefits in working memory.

Emotional interference and attentional control in schizophrenia-spectrum disorders: The special case of neutral faces

BACKGROUND AND OBJECTIVES

Schizophrenia-spectrum disorders (SSD) are characterized by impaired emotion processing and attention. SSD patients are more sensitive to the presence of emotional distractors. But despite growing interest on the emotion-attention interplay, emotional interference in SSD is far from fully understood. Moreover, research to date has not established the link between emotional interference and attentional control in SSD. This study thus aimed to investigate the effects of facial expression and attentional control in SSD, by manipulating perceptual load.

METHODS

Twenty-two SSD patients and 22 healthy controls performed a target-letter discrimination task with task-irrelevant angry, happy, and neutral faces. Target-letter was presented among homogenous (low load) or heterogenous (high load) distractor-letters. Accuracy and RT were analysed using (generalized) linear mixed-effect models.

RESULTS

Accuracy was significantly lower in SSD patients than controls, regardless of perceptual load and facial expression. Concerning RT, SSD patients were significantly slower than controls in the presence of neutral faces, but only at high load. No group differences were observed for angry and happy faces.

LIMITATIONS

Heterogeneity of SSD, small sample size, lack of clinical control group, medication.

CONCLUSIONS

One possible explanation is that neutral faces captured exogenous attention to a greater extent in SSD, thus challenging attentional control in perceptually demanding conditions. This may reflect abnormal processing of neutral faces in SSD. If replicated, these findings will help to understand the interplay between exogenous attention, attentional control, and emotion processing in SSD, which may unravel the mechanism underlying socioemotional dysfunction in SSD.

EXPRESS: Encoding Arm and Leg Movements in the Same or Opposite Direction

This study examined whether working memory performance for arm and leg movements differed when encoding in the same or opposite direction (relative to the observed direction) and which direction was better for encoding these two kinds of movements. The results showed that encoding direction regulated the comparison between arm and leg movements in working memory performance. In the same-direction encoding condition, arm movements performed better than leg movements, whereas in the opposite-direction encoding condition, arm movements performed worse. Additionally, arm movements performed better when they were encoded in the same direction, while encoding leg movements in the same direction did not differ from encoding them in the opposite direction. Therefore, we should move appropriate body parts for the same and opposite learning directions. The same direction is suitable for learning arm movements but not leg movements; the opposite direction is suitable for learning leg movements but not arm movements. We should also consider the appropriate learning direction for arm movements rather than leg movements. Arm movements are encoded more effectively in the same direction than in the opposite direction.

Subject-performed task effect on working memory performance in children with autism spectrum disorder

A previous study found that children with autism spectrum disorder (ASD) have better recall when they perform instructions (subject-performed task [SPT]) than when they passively hear instructions (verbal task [VT]) in a working memory task for instructions, an effect that is called the SPT effect. This study explored whether the SPT effect exhibited by ASD children is caused by the movement component or by processing materials twice. More importantly, this study explored whether intelligence influences the SPT effect exhibited by ASD children. ASD children with three levels of intelligence (N = 56) and a control group, children with intellectual disability (ID) who had low intelligence but did not have ASD (N = 21), were asked to perform working memory tasks for instructions under VT, SPT and repeated (hearing the instruction twice) conditions. No significant difference in performance was observed between the VT and repeated conditions, regardless of the child's level of intelligence. ASD children with lower-middle intelligence exhibited a smaller SPT effect than ASD children with upper-middle intelligence. Critically, while ASD children with low intelligence did not exhibit the SPT effect, an ID group with equivalent low intelligence did show this effect. Therefore, these results show that the SPT effect for ASD children is caused by the movement component and is uniquely associated with a certain level of intelligence, namely, lower middle and higher levels of intelligence. LAY SUMMARY: In ASD children, the benefit of physically performing instructions for working memory performance is uniquely associated with a certain level of intelligence. Only ASD children with lower-middle intelligence (and higher) benefit from physically performing instructions, and higher intelligence increases this benefit; ASD children with low intelligence do not show this benefit. This benefit in ASD children is attributed to the additional motoric code generated by physical performance.

Improving older adults' ability to follow instructions: benefits of actions at encoding and retrieval in working memory

The ability to follow instructions is critical for learning new skills and may support successful aging. Recent evidence indicates a close link between following instructions and working memory, and that action-based processing at encoding and retrieval can improve this ability. In this study, we examined the ability to follow instructions and the benefits of action-based processing in young and older adults. In Experiment 1, participants were presented with spoken or silent demonstrated instructions, then recalled them by oral repetition or physical enactment. Older adults produced fewer correct responses in all conditions. Both age groups were better at recalling demonstrated than spoken instructions in the verbal but not the enacted recall condition. Older adults also benefited from enacted recall relative to verbal recall, but to a smaller extent than younger adults. In Experiment 2, the additional benefit of dual modalities (spoken instructions with simultaneous demonstration) relative to single modality presentation (spoken instructions, or silent demonstration) was examined. Both age groups showed superior performance in dual modality conditions relative to spoken instructions when using verbal recall. These findings suggest that although following instruction ability appears to decline with age, older adults can still benefit from action at encoding and retrieval.

EXPRESS: Translating words into actions in working memory: the role of spatial-motoric coding

Research from a working memory perspective on the encoding and temporary maintenance of sequential instructions has established a consistent advantage for enacted over verbal recall. This is thought to reflect action planning for anticipated movements at the response phase. We describe five experiments investigating this, comparing verbal and enacted recall of a series of action–object pairings under different potentially disruptive concurrent task conditions, all requiring repetitive movements. A general advantage for enacted recall was observed across experiments, together with a tendency for concurrent action to impair sequence memory performance. The enacted recall advantage was reduced by concurrent action for both fine and gross concurrent movement with the degree of disruption influenced by both the complexity and the familiarity of the movement. The results are discussed in terms of an output buffer store of limited capacity capable of holding motoric plans for anticipated action.

Comparing motor imagery and verbal rehearsal strategies in children's ability to follow spoken instructions

The ability to follow spoken instructions is critical for children's learning in school and relies on the storage and processing of information in working memory. This study compared the effects of two encoding strategies (motor imagery and verbal rehearsal) on children's ability to follow spoken instructions in a working memory paradigm. A total of 146 children aged 7-12 years completed an instruction span task. In this task, children listened to a series of action-object commands and encoded them by either motor imagery or verbal rehearsal. They then attempted to recall the sequence in serial order by either enacted recall or verbal recall. Overall, children's ability to follow spoken instructions increased with age. In all age groups, children showed superior recall of instructions when they imagined the actions compared with verbal rehearsal of the actions during encoding, and this benefit of motor imagery was similar for verbal recall and enacted recall. Younger children reported motor imagery as more helpful than verbal rehearsal for remembering instructions, whereas older children considered verbal rehearsal as more useful. The study provides novel evidence for motor imagery as a superior strategy (relative to verbal rehearsal) for remembering spoken instructions in school-age children.

Forward and backward recall of serial actions: Exploring the temporal dynamics of working memory for instruction

The ability to flexibly retrieve and implement sequences of actions is essential to motor learning and planning. Recent research has indicated that serial memory for instructions is influenced by presentation modality (spoken vs. visual demonstration) and recall modality (verbal vs. enacted recall). The present study extended this work by investigating the impact of recall direction (forward vs. backward), in addition to that of presentation and recall modality, on working memory for instruction sequences in healthy young adults. Experiment 1 (N = 24) showed that adults were more accurate in backward than forward verbal recall following spoken instructions. In contrast, enacted recall was not influenced by recall direction. Experiment 2 (N = 24) used visual demonstration of instruction sequences and found similar performance levels in forward and backward recall. Experiment 3 (N = 24) replicated the findings from Experiment 1 and 2, along with the previous observation of an advantage for demonstrated over spoken presentation. In addition, the beneficial effects of enacted recall and visual demonstration also emerged in an analysis of response times, specifically in reduced preparation and recall duration. Demonstrated instructions improved maintenance of all items while backward recall enhanced memory of later items in the sequence. These findings provide new insights into the cognitive processes and temporal dynamics of working memory for serial actions and instructions.