Letter Rotation Task Research Articles

The benefit of choice on task performance: Reduced difficulty effects in free-choice versus forced-choice tasks.

We investigated how self-determined (free) versus imposed (forced) choices influence task performance. To this end, we examined how changes in perceptual and central decision-processing difficulties affect task performance in an environment where free-choice and forced-choice tasks were intermixed. In Experiments 1 (N = 43) and 2 (N = 42), perceptual processing difficulty was varied by altering colored dot proportions (easy vs. hard color discrimination task). In Experiment 3 (N = 58), decision-processing difficulty was adjusted by changing the rotation degree of letters (easy vs. hard letter rotation task). Across all experiments, both free-choice and forced-choice performance were more impaired with harder stimuli, but this effect was generally less pronounced in freely chosen tasks. Specifically, this was evident from significant interactions between processing mode (free vs. forced) and difficulty (easy vs. hard) in the mean reaction times (RTs) for the tasks with the difficulty manipulation. Thus, processing in free-choice tasks is generally less affected by environmental changes (i.e., variation in information difficulties). We discuss how the benefit of self-determined choices over imposed choices can be explained by motivational and performance-optimization accounts, while also considering the finding that participants adjusted their task choices toward tasks with easier stimuli (i.e., significant main effect of task difficulty on choosing the task with the difficulty manipulation). Specifically, we discuss how having control over task choices might lead to more stable information processing and allow people to choose more difficult tasks when this increased difficulty has a relatively small impact on their performance.

The time course of planar and non-planar rotations in a letter rotation task

Mental rotation (MR) of character letters requires participants to mentally rotate the letter in their minds’ eyes through a process akin to the physical rotation of the stimulus. It has been suggested that different cognitive processes are engaged during such MR of both canonical and mirror-reversed letters. In addition to the planar rotation of the canonical letters, an additional “flip-over” process (non-planar rotation) has been assumed during the MR of mirror-reversed letters. However, the temporal relationship between planar and non-planar rotation has not been systematically investigated. In this study, the occurrence of both planar and non-planar rotations were examined through the analysis of the event-related brain potentials (ERPs) elicited by canonical or mirror-reversed letters presented at different rotation angles between 300 and 1000 ms post-stimulus onset over consecutive 50ms time-windows. For smaller rotation angles (30° and 60°), non-planar rotation preceded planar rotation. For letters rotated by 90°, planar and non-planar rotation occurred at the same time. For larger angles (120° and 150°), the letter was first rotated within the plane (planar rotation) and afterwards it was also rotated out-of-the-plane (non-planar rotation) until it was fully canonicalized. Thus, the temporal relationship between planar and non-planar rotation differed for each rotation angle, with the non-planar rotation occurring at increasingly later intervals for different points in time for progressively larger rotation angles. These findings have relevant methodological implications for studies investigating the psychophysiological correlates of the mental rotation of mirror letters.

Semantic interference is not modality specific: Evidence from sound naming with distractor pictures.

In three experiments, participants named environmental sounds (e.g., the bleating of a sheep by producing the word "sheep") in the presence of distractor pictures. In Experiment 1, we observed faster responses in sound naming with congruent pictures (e.g., sheep; congruency facilitation) and slower responses with semantically related pictures (e.g., donkey; semantic interference), each compared with unrelated pictures (e.g., violin). In Experiments 2 and 3, we replicated these effects and used a psychological refractory period approach (combining an arrow decision or letter rotation task as Task 1 with sound naming as Task 2) to investigate the locus of the effects. Congruency facilitation was underadditive with dual-task interference suggesting that it arises, in part, during pre-central processing stages in sound naming (i.e., sound identification). In contrast, semantic interference was additive with dual-task interference suggesting that it arises during central (or post-central) processing stages in sound naming (i.e., response selection or later processes). These results demonstrate the feasibility of sound naming tasks for chronometric investigations of word production. Furthermore, they highlight that semantic interference is not restricted to the use of target pictures and distractor words but can be observed with quite different target-distractor configurations. The experiments support the view that congruency facilitation and semantic interference reflect some general cognitive mechanism involved in word production. These results are discussed in the context of the debate about semantic-lexical selection mechanisms in word production.

Spatial and egocentric mental rotation in patients with cervical dystonia.

Mental rotation has attracted the interest of cognitive research on dystonia, but at the moment, contrasting data are available on whether this complex cognitive ability is impaired in the disorder. Here, we assessed spatial and egocentric mental rotation in patients with cervical dystonia (CD). Patients with CD and healthy controls were required to perform a letter rotation task (spatial mental rotation) and to judge laterality of front-facing and back-facing human images (egocentric mental rotation). CD patients were selectively impaired on letter rotation, whereas they did not differ from controls when judging laterality of both front-facing and back-facing bodies. These findings support the view according to which neural circuits involved in spatial processing are dysfunctional in CD.

Age-associated delay in mental rotation.

Age-associated slowing in mental rotation (MR) process has been documented in the literature. Particularly, the intercept of the response times function of rotation angle has been consistently found to be larger in older than in younger adults. However, the intercept represents the speed of response in 2 distinct subprocesses of MR: the initial phase of stimulus encoding and the final phase of response selection and execution. Thus, it remains unclear which of these 2 subprocesses of MR is affected by age. To investigate this, we recorded event-related potentials in younger and older individuals during a letter rotation task. The onset of the rotation-related negativity (RRN), the electrophysiological correlate of MR, was delayed in older (n = 20; mean age = 20.1) as compared to younger participants (n = 20, mean age = 73.4). Consistent with this observation, additional analyses revealed that the RRN amplitude was modulated by rotation angle between 350 and 500 ms poststimulus in younger adults (n = 26, mean age = 21.0), while this modulation only emerged in the later time window (500-650 ms) in older participants (n = 26; mean age = 73.6). These results suggest that MR occurs later in older adults and demonstrate that the initial phase before MR proper is one source of the age-related slowing observed in MR tasks. Possible accounts for this age-associated delay include a prolonged phase of stimulus encoding and/or selective difficulties in directing attention away from the external stimulus toward its internal mental representation. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

When I am (almost) 64: The effect of normal ageing on implicit motor imagery in young elderlies

Motor imagery (M.I.) is a cognitive process in which movements are mentally evoked without overt actions. Behavioral and fMRI studies show a decline of explicit M.I. ability (e.g., the mental rehearsal of finger oppositions) with normal ageing: this decline is accompanied by the recruitment of additional cortical networks.However, none of these studies investigated behavioral and the related fMRI ageing modifications in implicit M.I. tasks, like the hand laterality task (HLT).To address this issue, we performed a behavioral and fMRI study: 27 younger subjects (mean age: 31 years) and 29 older subjects (mean age: 61 years) underwent two event-related design fMRI experiments. In the HLT, participants were asked to decide whether a hand rotated at different angles was a left or right hand. To test the specificity of any age related difference in the HLT, we used a letter rotation task as a control experiment: here subjects had to decide whether rotated letters were presented in a standard or a mirror orientation.We did not find any group difference in either behavioral task; however, we found significant additional neural activation in the elderly group in occipito-temporal regions: these differences were stronger for the HLT rather than for the LRT with group by task interactions effects in right occipital cortices.We interpret these results as evidence of compensatory processes associated with ageing that permit a behavioral performance comparable to that of younger subjects. This process appears to be more marked when the task specifically involves motor representations, even when these are implicitly evoked.

Cognitive mapping deficits in schizophrenia: Evidence from clinical correlates of visuospatial transformations

The ‘cognitive mapping’ component of spatial cognition, namely – the allocentric/egocentric function and its relation to symptoms in schizophrenia is relatively unexplored. In this study, we compared schizophrenia patients (N=44) to demographically-matched healthy controls (N=43) using computer-administered visuospatial transformation tasks with egocentric and allocentric components and analyzed their correlation with symptoms. Significant diagnosis X task-type interaction effect was seen on task accuracy. Patients performed significantly worse than controls in the allocentric letter rotation task (LRT) but not in the egocentric people rotation task (PRT). Accuracy in the LRT was significantly lesser than in PRT among patients but not among controls. Patients were significantly slower as compared to controls in both tasks. Both groups took longer to perform PRT as compared to LRT. LRT accuracy showed significant negative correlation with total positive symptoms as well as negative symptoms scores. Angle of rotation, perspective (front-facing/back-facing), orientation (mirrored/normal), and stimulus type (letter/number) were found to significantly influence performance in both groups of subjects. The present data support the finding that there is a differential impairment of allocentric abilities in schizophrenia patients. Further systematic research in this area may facilitate better understanding of schizophrenia pathogenesis.

The role of embodied simulation in mental transformation of whole-body images: Evidence from Parkinson’s disease

It has been repeatedly demonstrated that mentally performing an action and mentally transforming body-parts entail simulation of one’s own body movements, consistent with predictions of embodied cognition theories. However, the involvement of embodied simulation in mental transformation of whole-body images is still disputed. Here, we assessed own body transformation in Parkinson’s disease (PD) patients with symptoms most affecting the left or the right body side. PD patients were required to perform left–right judgments on front-facing or back-facing human figures, and a letter rotation task. Results demonstrated that PD patients were selectively impaired in judging the side of back-facing human figures corresponding to their own most affected side, but performed as well as healthy subjects on mental transformation of front-facing bodies and on letter rotation. These findings demonstrate a parallel impairment between motor and mental simulation mechanisms in PD patients, thus highlighting the specific contribution of embodied cognition to mental transformation of whole-body images.

Empathy, schizotypy, and visuospatial transformations

Introduction. Adopting another person's visuospatial perspective has been associated with empathy, which involves adopting the psychological perspective of another individual. Both reduced empathy and abnormal visuospatial processing have been observed in those with schizophrenia and schizophrenia-related personality traits. In the current study, we sought to explore the relationship between empathy, schizotypy, and visuospatial transformation ability. Methods. 32 subjects (16 women) performed a visuospatial perspective-taking task and a mental letter rotation task. Response times and accuracy were analysed in relation to dimensions of self-reported empathy, indexed using the Interpersonal Reactivity Index, and schizotypy, as measured by the Schizotypal Personality Questionnaire. Results. We found that: (1) greater cognitive and affective empathy were associated with reduced negative schizotypy, and, in men, greater cognitive empathy was associated with reduced positive schizotypy; (2) improved accuracy for imagined self–other transformations in the perspective-taking task was associated with greater self-reported cognitive empathy in women and higher positive schizotypy across genders; (3) faster mental letter rotation was associated with reduced cognitive empathy and increased negative schizotypy in women. Conclusions. Together, the findings partially support the commonalities in visuospatial transformation ability, empathy, and schizotypy, and posit an interesting link between spatial manipulations of our internal representations and interactions with the physical world.

Action observation improves motor imagery: specific interactions between simulative processes

In the present study, we demonstrated that observation of hand rotation had specific facilitation effects on a classical motor imagery task, the hand-laterality judgement. In Experiment 1, we found that action observation improved subjects' performance on the hand laterality but not on the letter rotation task (stimulus specificity). In Experiment 2, we demonstrated that this facilitation was not due to mere observation of a moving hand, because it was triggered by observation of manual rotation but not of manual prehension movements (motion specificity). In Experiment 3, this stimulus- and motion-specific effect was found to be right hand-specific, compatible with left-hemispheric specialization in motor imagery but not in action observation. These data provided direct support to the idea that different simulation states, such as action observation and motor imagery, share some common mechanisms but also show specific functional differences.

Motor Imagery Development in Primary School Children

Motor imagery provides a unique window on the integrity of movement representation. How this ability unfolds during development remains unknown, however. It was the aim of this cross-sectional study to chart the development of movement imagery over childhood using validated measures, and to examine its relationship to movement skill. A sample of 58 children aged 7–12 years were recruited from Australian primary schools. Motor imagery ability was assessed using the Radial Pointing Task and a (mental) Hand Rotation Task, whereas visual (or object-related) imagery was measured on a Letter Rotation Task. Motor skill was assessed on the McCarron Assessment of Neuromuscular Development (MAND). Results showed clear age differences on all measures: motor skill, motor imagery, and visual imagery. The relationship between motor imagery and motor skill was shown to become stronger with age, whereas no relationship between visual imagery and motor skill was evident at any age. Taken together, these results show that motor imagery has a distinct developmental trajectory that is entwined with the development of movement skill in children. We argue that movement imagery reflects the unfolding of internal modeling processes providing the foundation for adaptive, goal-directed movements.

THE PROCESSING-STORAGE RELATIONSHIP IN WORKING MEMORY SPAN: FROM A PERSPECTIVE OF A REPRESENTATION-BASED INTERFERENCE VIEW

Recent studies using working memory (WM) span tests have reported that processing activities negatively affected memory performance on the one hand and storage activities adversely affected processing efficiency on the other hand. We examined this processing-storage relationship in two WM span tests that required participants to maintain spatial or verbal memory items while engaging in mental letter rotation, focusing on an interference effect derived from this visuospatial processing task. Results showed that the mental letter rotation task interfered with memory of verbal as well as spatial items, indicating the similarity of these two span tests. Furthermore, the two span tests produced a proportional slowdown in processing speed toward the end of each span list. We discussed possible mechanisms in which the processing and maintenance activities disturb each other from the perspectives of domain-specific representation-based interference and domain-general attentional switching in working memory.

Motor initiation and execution in patients with conversion paralysis

Motor initiation and motor execution in four patients with conversion paralysis were investigated in a non-affected motor modality (speech). In line with the hypothesis of dissociated control in conversion disorder [Cognit. Neuropsychiatry 8 (1) (2001) 21] motor initiation, but not response duration, was expected to be impaired. The motor initiation times (reaction time: RT) and motor execution times (response duration: RD) were compared on four RT-tasks that required the production of a verbal response: a simple choice RT-task, a mental letter rotation task, and an implicit and an explicit mental hand rotation task. Because conversion disorder is expected to primarily involve an impairment in the initiation of movement, we expected the following task characteristics to uniquely affect RT and not RD: type of instruction (implicit versus explicit instructed imagery), angle of rotation, and target arm (affected versus non-affected arm). The results indeed showed the task characteristics to significantly affect the participants' RT and not their RD. It was concluded that conversion paralysis is associated with a specific impairment in the explicit initiation of processes with a spatial and motor component.