RESUMO
The purpose of this study was to examine the effects on prefrontal cortex (PFC) activity of listening to pleasant sounds (PS) while walking, gum chewing (GCh), or performing the dual task of walking and gum chewing at the same time (walking + GCh). A total of 11 healthy adult male volunteers participated in the study (mean age: 29.54 ± 3.37). The block design of the trial consisted of a 30-sec rest, a 60-sec task (target task or control task), and a 30-sec rest. There were three target task conditions: walking, GCh, and the dual task. All of these were performed while listening to PS. The control condition was rest (no exercise) while listening to PS. The outcomes measured and measurements used were PFC activity using two-channel near-infrared spectroscopy and participant self-evaluation of the pleasantness of the experience using the visual analogue scale (VAS). Compared to the control condition, there was significantly greater PFC activation during the GCh and the walking + GCh tasks. Compared to the control condition, GCh and walking + GCh showed significantly greater activation on the VAS measure. In conclusion, listening to PS while GCh or walking + GCh increases PFC activity in the lower central region and induces positive emotional change.
Assuntos
Goma de Mascar , Mastigação , Córtex Pré-Frontal , Humanos , Córtex Pré-Frontal/fisiologia , Masculino , Adulto , Mastigação/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Caminhada/fisiologia , Estimulação Acústica/métodosRESUMO
BACKGROUNDS: Gait disorder is associated with cognitive functional impairment, and this disturbance is more pronouncedly when performing additional cognitive tasks. Our study aimed to characterize gait disorders in mild cognitive impairment (MCI) under three dual tasks and determine the association between gait performance and cognitive function. METHODS: A total of 260 participants were enrolled in this cross-sectional study and divided into MCI and cognitively normal control. Spatiotemporal and kinematic gait parameters (31 items) in single task and three dual tasks (serial 100-7, naming animals and words recall) were measured using a wearable sensor. Baseline characteristics of the two groups were balanced using propensity score matching. Important gait features were filtered using random forest method and LASSO regression and further described using logistic analysis. RESULTS: After matching, 106 participants with MCI and 106 normal controls were recruited. Top 5 gait features in random forest and 4 ~ 6 important features in LASSO regression were selected. Robust variables associating with cognitive function were temporal gait parameters. Participants with MCI exhibited decreased swing time and terminal swing, increased mid stance and variability of stride length compared with normal control. Subjects walked slower when performing an extra dual cognitive task. In the three dual tasks, words recall test exhibited more pronounced impact on gait regularity, velocity, and dual task cost than the other two cognitive tests. CONCLUSION: Gait assessment under dual task conditions, particularly in words recall test, using portable sensors could be useful as a complementary strategy for early detection of MCI.
Assuntos
Disfunção Cognitiva , Humanos , Idoso , Estudos Transversais , Disfunção Cognitiva/psicologia , Marcha , Caminhada , Cognição , Testes NeuropsicológicosRESUMO
OBJECTIVES: This study aimed to identify how different dual tasks influence speech performance among young Malay speakers by manipulating the complexity of sentences. Fifteen female speakers (20-30 years old) were audio recorded while executing a series of simple and complex sentence repetition tasks. METHODS: Hierarchical linear modeling was conducted to examine the effects of task (speech task only, speech + cognitive tasks, speech + linguistic tasks, and speech + manual tasks) and sentence complexity (simple vs. complex), as well as their interaction on 3 outcome measures (word accuracy rate [WAR], response reaction time [RRT], and duration of sentence [DoS]). RESULTS: Significantly higher WAR were found when participants read the sentences only compared to when they completed another task simultaneously. The pairwise comparison further revealed that the conditions of speech + manual tasks produced the lowest WAR. For RRT, participants responded significantly faster when they only read the sentences (mean = 1.36, SE = 0.17) than when they read the sentences and conducted another task at the same time (mean = 1.66, SE = 0.14; p < 0.0001). A pairwise comparison showed that the conditions of speech + manual tasks produced the longest DoS. Neither the effect of sentence complexity nor the interaction between task and sentence complexity was statistically significant across WAR, RRT, and DoS. CONCLUSIONS: The results augment what is known about interference between speech and other concurrent tasks and provides evidence that divided attention affects manual task performance more than other tasks. In addition, sentence complexity did not affect speech performance in healthy adults. This paradigm could be used in future studies to serve as a clinical marker that can potentially distinguish mild cognitive impairment from normal aging.
Assuntos
Percepção da Fala , Fala , Adulto , Feminino , Humanos , Idioma , Linguística , Malásia , Fala/fisiologia , Adulto JovemRESUMO
Recent dual-task studies observed worse performance in task-pair switches than in task-pair repetitions and interpreted these task-pair switch costs as evidence that the identity of the two individual tasks performed within a dual task is jointly represented in a single mental representation, termed "task-pair set." In the present study, we conducted two experiments to examine (a) whether task-pair switch costs are due to switching cues or/and task pairs and (b) at which time task-pair sets are activated during dual-task processing. In Experiment 1, we used two cues per task-pair and found typical dual-task interference, indicating that performance in the individual tasks performed within the dual task deteriorates as a function of increased temporal task overlap. Moreover, we observed cue switch costs, possibly reflecting perceptual cue priming. Importantly, there were also task-pair switch costs that occur even when controlling for cue switching. This suggests that task-pair switching per se produces a performance cost that cannot be reduced to costs of cue switching. In Experiment 2, we employed a go/no-go-like manipulation and observed task-pair switch costs after no-go trials where subjects prepared for a task-pair, but did not perform it. This indicates that task-pair sets are activated before performing a dual task. Together, the findings of the present study provide further evidence for a multicomponent hierarchical representation consisting of a task-pair set organized at a hierarchically higher level than the task sets of the individual tasks performed within a dual task.
Assuntos
Atividade Motora , Sinais (Psicologia) , Humanos , Desempenho Psicomotor , Tempo de ReaçãoRESUMO
OBJECTIVE: The aim of this pilot study was to investigate differences on dual- and triple-task performance in institutionalized prefrail and frail older adults. Performance on these tasks is relevant since many activities of daily living involve simultaneous motor and cognitive tasks. METHODS: We used a phenotypic description of frailty based on the presence or absence of five criteria related to physical fitness and metabolism (unintentional weight loss, self-reported exhaustion, muscle weakness, low gait speed, and low physical activity). Thirty-three institutionalized older adults (≥ 65 years, 78.8% females) were divided according to their frailty status. Participants completed cognitive tasks (a phonemic verbal fluency task and a visuospatial tracking task) while cycling on a stationary cycle (upper- and lower-extremity function was assessed). Cycling (number of arm and foot cycles) and cognitive (number of correct answers) performances were measured during single-, dual-, and triple-task conditions. Performances and costs of dual -and triple- tasking on cycling and cognitive performances were compared between prefrail and frail groups. RESULTS: Prefrail and frail older adults did not differ in their performance in dual-tasks; however, frail older adults showed a poorer performance in the triple-task. CONCLUSIONS: Although future studies need to confirm our observations in larger samples, this pilot study suggests that developing new tools based on triple tasking could be useful for the comprehensive assessment of frailty.
Assuntos
Idoso Fragilizado , Análise e Desempenho de Tarefas , Atividades Cotidianas , Idoso , Feminino , Avaliação Geriátrica , Humanos , Masculino , Projetos PilotoRESUMO
This study examines dual-task performance in the tactile modality and tests whether dual-task cost depends on task type. Experiment 1 involved competing tasks of the same type, using a primary localisation task on the left hand and a secondary localisation task on the right hand. In Experiment 2, the primary task on the left hand remained the same, while an intensity discrimination task was used as the secondary task on the right hand. Subjects in both experiments completed three conditions: the primary task alone, a dual-task condition, and the primary task with the secondary stimulus present but no response required. Across both experiments, performance on the primary task was best when it was presented alone, and there was a performance decrement when the secondary stimulus was present but not responded to. Performance on the primary task was further decreased when participants had to respond to the secondary stimulus, and the decrease was larger when the secondary task was localisation rather than discrimination. This result indicates that task type in the tactile modality may modulate the attentional cost of dual-task performance and implies partially shared resources underlie localisation and intensity discrimination.
Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Percepção do Tato/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
OBJECTIVE: To examine the role of cue utilization in the management of interruptions during a high workload, rail control simulation. BACKGROUND: High-risk, high-consequence environments are characterized by cognitively demanding, time-critical activities, in which operators are required to manage frequent interruptions under conditions of high workload. Interruptions are deleterious to performance as they impose excessive cognitive demand on limited working memory resources, thereby depleting residual resources for the primary task. Cue utilization may enable superior performance in managing interruptions through efficiencies gained by the application of implicit patterns stored in long-term memory. METHOD: Two experiments were conducted. In Experiment 1, 46 university students undertook an assessment of cue utilization and subsequently engaged in a high workload, simulated rail control task while managing multiple interruptive tasks. Experiment 2 replicated and extended Experiment 1, wherein 52 university students completed a measure of cue utilization and engaged in a high workload, simulated rail control task while managing multiple interruptions and breaks. RESULTS: The analyses revealed that participants who demonstrated a greater capacity for cue utilization also demonstrated a reduced loss of performance following interruptions. CONCLUSION: The outcomes suggest a relationship between a greater capacity for cue utilization and superior performance in the management of interruptions in high workload conditions. APPLICATION: Assessments of cue utilization may assist in the selection and training of operators in high-consequence, high-risk environments, to ensure efficient and accurate performance during the management of interruptions.
Assuntos
Atenção , Sinais (Psicologia) , Memória de Curto Prazo , Análise e Desempenho de Tarefas , Carga de Trabalho , Adolescente , Feminino , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: Suicide is a major public health problem, and it remains unclear which processes link suicidal ideation and plans to the act of suicide. Growing evidence shows that the majority of suicidal patients diagnosed with major depression or bipolar disorder report repetitive suicide-related images and thoughts (suicidal intrusions). Various studies showed that vividness of negative as well as positive intrusive images may be reduced by dual task (e.g. eye movements) interventions taxing the working memory. We propose that a dual task intervention may also reduce frequency and intensity of suicidal imagery and may be crucial in preventing the transition from suicidal ideation and planning to actual suicidal behaviour. This study aims a) to evaluate the effectiveness of an Eye Movement Dual Task (EMDT) add-on intervention targeting suicidal imagery in depressed patients, b) to explore the role of potential moderators and mediators in explaining the effect of EMDT, and c) to evaluate the cost-effectiveness of EMDT. METHODS: We will conduct a multi-center randomized clinical trial (RCT) evaluating the effects of EMDT in combination with usual care (n = 45) compared to usual care alone (n = 45). Participants will fill in multiple online batteries of self-report questionnaires as well as complete a semi-structured interview (Intrusion Interview), and online computer tasks. The primary outcome is the frequency and intrusiveness of suicidal imagery. Furthermore, the vividness, emotionality, and content of the suicidal intrusions are evaluated; secondary outcomes include: suicidal behaviour and suicidal ideation, severity of depression, psychological symptoms, rumination, and hopelessness. Finally, potential moderators and mediators are assessed. DISCUSSION: If proven effective, EMDT can be added to regular treatment to reduce the frequency and vividness of suicidal imagery. TRIAL REGISTRATION: The study has been registered on October 17th, 2018 at the Netherlands Trial Register, part of the Dutch Cochrane Centre ( NTR7563 ).
Assuntos
Análise Custo-Benefício/métodos , Dessensibilização e Reprocessamento através dos Movimentos Oculares/economia , Dessensibilização e Reprocessamento através dos Movimentos Oculares/métodos , Movimentos Oculares/fisiologia , Ideação Suicida , Adulto , Transtorno Depressivo/economia , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Suicídio/psicologia , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Dynamic balance keeps the vertical projection of the center of mass within the base of support while walking. Dynamic balance tests are used to predict the risks of falls and eventual falls. The psychometric properties of most dynamic balance tests are unsatisfactory and do not comprise an actual loss of balance while walking. OBJECTIVES: Using beam walking distance as a measure of dynamic balance, the BEAM consortium will determine the psychometric properties, lifespan and patient reference values, the relationship with selected "dynamic balance tests," and the accuracy of beam walking distance to predict falls. METHODS: This cross-sectional observational study will examine healthy adults in 7 decades (n = 432) at 4 centers. Center 5 will examine patients (n = 100) diagnosed with Parkinson's disease, multiple sclerosis, stroke, and balance disorders. In test 1, all participants will be measured for demographics, medical history, muscle strength, gait, static balance, dynamic balance using beam walking under single (beam walking only) and dual task conditions (beam walking while concurrently performing an arithmetic task), and several cognitive functions. Patients and healthy participants age 50 years or older will be additionally measured for fear of falling, history of falls, miniBESTest, functional reach on a force platform, timed up and go, and reactive balance. All participants age 50 years or older will be recalled to report fear of falling and fall history 6 and 12 months after test 1. In test 2, seven to ten days after test 1, healthy young adults and age 50 years or older (n = 40) will be retested for reliability of beam walking performance. CONCLUSION: We expect to find that beam walking performance vis-à-vis the traditionally used balance outcomes predicts more accurately fall risks and falls. CLINICAL TRIAL REGISTRATION NUMBER: NCT03532984.
Assuntos
Acidentes por Quedas/estatística & dados numéricos , Esclerose Múltipla/fisiopatologia , Doença de Parkinson/fisiopatologia , Equilíbrio Postural/fisiologia , Transtornos de Sensação/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Caminhada , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Adulto JovemRESUMO
Executive functioning of two simultaneous component tasks in dual-task situations is primarily associated with activation of the lateral prefrontal cortex (PFC), as demonstrated in functional imaging studies. However, the precise role of the lateral PFC and the causal relation between this area's activity and executive functioning in dual tasks has exclusively been demonstrated for the left lateral PFC so far. To investigate this relation for the right lateral PFC, we used anodal transcranial direct current stimulation (atDCS; 1 mA, 20 min) in contrast to sham stimulation (1 mA, 30 s) in Experiment 1 (N = 30) as well as cathodal transcranial direct current stimulation (ctDCS; 1 mA, 20 min) in contrast to sham stimulation (1 mA, 30 s) in Experiment 2 (N = 25) over the right inferior frontal junction under conditions of random task order in dual tasks; random dual tasks require decisions on task order and thus high demands on executive functioning. Across these experiments, our results showed different tDCS-related effects: while atDCS improved performance evident from reduced error rates (Experiment 1), ctDCS impaired dual-task performance and increased these rates (Experiment 2). Moreover, baseline performance correlated with tDCS-induced performance changes, indicating that baseline performance was associated with atDCS-induced improvement. Our findings suggest that dual-task performance is causally related to right lateral PFC activation under conditions that require executive functioning as well as cognitive control of task sets and task order.
Assuntos
Função Executiva/fisiologia , Lateralidade Funcional/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
To examine whether hierarchical higher level task representations comprising the task sets of Task 1 (T1) and Task 2 (T2) are activated within each trial in dual-task situations, we combined the psychological refractory period (PRP) paradigm with the task-pair switching logic (Hirsch et al. 2017). In Experiment 1, in which subjects switched between task-pairs including a varying T1 and a constant T2, we found a PRP effect (i.e., worse performance with short stimulus onset asynchrony [SOA] than with long SOA) and task-pair switch costs in T1 and T2 (impaired performance in task-pair switches compared to task-pair repetitions). However, since in Experiment 1 there were no forward and backward response-response compatibility effects that indicated interference between T1 and T2, we could not exclude that the activation of T1 persisted into the next trial despite the intervening T2, and hence, that task-pair switch costs are due to repetition-priming effects of T1 across task-pairs rather than due to persisting activation of task-pair representations. In Experiment 2, we used a modified task-pair switching logic with a constant T1 and a varying T2, and replicated task-pair switch costs under conditions that not only rule out repetition-priming effects of T1 across task-pairs as the source of task-pair switch costs but also disentangle the effects of switching task-pairs from those of switching T1. These effects were associated in previous studies using the original task-pair switching logic. Thus, the findings of the present study strongly suggest that hierarchical higher level task representations are activated during dual-task processing.
Assuntos
Comportamento Multitarefa , Período Refratário Psicológico , Atenção , Feminino , Humanos , Masculino , Tempo de Reação , Priming de Repetição , Adulto JovemRESUMO
[Purpose] The purpose of this study was to evaluate the effect of dual-task gait training on foot pressure in elderly women. [Subjects and Methods] Twenty elderly people in local communities performed dual-task gait training for 20 minutes three times per week for 8 weeks. Foot pressure was measured using an F-scan System (Tekscan, South Boston, MA, USA) before the intervention and in the 4th and 8th weeks of the intervention. [Results] Foot pressure increased significantly between the 4th and 8th weeks of the intervention in the CFF (central forefoot); between before the intervention and the 4th week, between the 4th and 8th weeks, and between before the intervention and the 8th week in the MF (midfoot); and between before the intervention and the 4th and 8th weeks in the HL (heel). [Conclusion] The results of this study indicate that dual-task gait training may improve the gait ability of elderly persons residing in the community.
RESUMO
In this study, we examined whether experience level and various dual motor and cognitive or single tasks influenced young soccer players' physical performance during small-sided games. Participants were 72 players from U-13 (n = 36) and U-17 (n = 36) groups who participated in 3-to-a-side small-sided games under four experimental conditions: control, a secondary motor task, an additional related secondary cognitive task, and an additional secondary non-specific task. We used GPS devices to measure physical performance in terms of distances covered and accelerations at different thresholds. We found no significant interaction effect between player experience and task condition (p = .540), meaning that dual tasks had comparable effects on players of different experience levels. There were significant main effects of both experience level (p < .001) and condition (p < .001) on most physically related variables. Older players outperformed younger ones, particularly in high-intensity actions. While secondary motor tasks decreased physical performance, secondary cognitive tasks, irrespective of specificity, did not impair players' performances. In conclusion, experience level did not influence the players' physical response to dual tasks, and a secondary motor task was more disruptive to physical performance than either of two types of secondary cognitive tasks. Cognitive tasks can be incorporated into soccer training without compromising physical performance.
Assuntos
Desempenho Atlético , Futebol , Humanos , Futebol/fisiologia , Futebol/psicologia , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Masculino , Adolescente , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Fatores EtáriosRESUMO
BACKGROUND: Beam walking is a new test to estimate dynamic balance. We characterized dynamic balance measured by the distance walked on beams of different widths in five age groups of healthy adults (20, 30, 40, 50, 60 years) and individuals with neurological conditions (i.e., Parkinson, multiple sclerosis, stroke, age: 66.9 years) and determined if beam walking distance predicted prospective falls over 12 months. METHODS: Individuals with (n = 97) and without neurological conditions (n = 99, healthy adults, age 20-60) participated in this prospective longitudinal study. Falls analyses over 12 months were conducted. The summed distance walked under single (walking only) and dual-task conditions (walking and serial subtraction by 7 between 300 to 900) on three beams (4, 8, and 12-cm wide) was used in the analyses. Additional functional tests comprised grip strength and the Short Physical Performance Battery. RESULTS: Beam walking distance was unaffected on the 12-cm-wide beam in the healthy adult groups. The distance walked on the 8-cm-wide beam decreased by 0.34 m in the 20-year-old group. This reduction was ~ 3 × greater, 1.1 m, in the 60-year-old group. In patients, beam walking distances decreased sharply by 0.8 m on the 8 versus 12 cm beam and by additional 1.6 m on the 4 versus 8 cm beam. Beam walking distance under single and dual-task conditions was linearly but weakly associated with age (R2 = 0.21 for single task, R2 = 0.27 for dual-task). Age, disease, and beam width affected distance walked on the beam. Beam walking distance predicted future falls in the combined population of healthy adults and patients with neurological conditions. Based on receiver operating characteristic curve analyses using data from the entire study population, walking ~ 8.0 of the 12 m maximum on low-lying beams predicted future fallers with reasonable accuracy. CONCLUSION: Balance beam walking is a new but worthwhile measure of dynamic balance to predict falls in the combined population of healthy adults and patients with neurological conditions. Future studies are needed to evaluate the predictive capability of beam walking separately in more homogenous populations. Clinical Trial Registration Number NCT03532984.
RESUMO
Words judged for relevance in a survival situation are remembered better than words judged for relevance in a nonsurvival context. This survival processing effect has been explained by selective tuning of human memory during evolution to process and retain information specifically relevant for survival. According to the richness-of-encoding hypothesis the survival processing effect arises from a domain-general mechanism-namely, a particularly rich and distinct form of encoding. This form of information processing is effortful and requires limited cognitive capacities. In our experiment, we used the well-established psychological refractory period framework in conjunction with the effect propagation logic to assess the role of central cognitive resources for the survival processing effect. Our data demonstrate that the survival memory advantage indeed relies on the capacity-limited central stage of cognitive processing. Thus, rating words in the context of a survival scenario involves central processing resources to a greater amount than rating words in a nonsurvival control condition. We discuss implications for theories of the survival processing effect.
Assuntos
Rememoração Mental , Período Refratário Psicológico , Humanos , Cognição , LógicaRESUMO
Background: Chronic obstructive pulmonary disease (COPD) is characterized by important extrapulmonary alterations that could affect the performance in dual task (DT) (motor and cognitive tasks executed simultaneously), which is defined as DT interference (DTI). Objective: To compare the performance of DT between individuals with COPD and healthy control subjects (HCSs). Methods: The literature search was conducted in seven databases (Medline, Scopus, Web of Science, PEDro, SciELO, LILACS, and Google Scholar) up to December 2023, including studies published in English, Spanish, or Portuguese. Studies with individuals diagnosed with COPD older than 60 years, who were evaluated with any DT assessment, and compared with HCS were included. The quality of the studies was evaluated using the risk of bias in nonrandomized studies of interventions (ROBINS-I). The meta-analysis was performed with JAMOVI software 5.4. The study protocol was registered on PROSPERO (CRD42023435212). Results: From a total of 128 articles, 5 observational studies were selected in this review, involving 252 individuals aged between 60 and 80 years, from France, Italy, Canada, Turkey, and Belgium. Notable DTI was observed in individuals with COPD compared to HCS (standard mean difference [SMD] = 0.91; 95% confidence interval (CI) 0.06-1.75, p = 0.04). Individuals with COPD had impaired gait speed, balance control, muscle strength, and cognitive interference during DT compared to HCS. DT assessment protocols included different combination of motor and cognitive tasks, using functional test, gait analysis, and muscle strength paired with countdown and verbal fluency tasks. Studies presented low (n = 2), moderate (n = 1), and serious (n = 2) overall risk of bias. Conclusion: Older adults diagnosed with COPD exhibited a significant DTI compared to HCSs, which is characterized by poorer physical and cognitive performance during DT execution. These findings highlight the importance of incorporating DT assessments into clinical practice for individuals with COPD.
Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Cognição/fisiologia , Análise e Desempenho de Tarefas , Idoso , Pessoa de Meia-IdadeRESUMO
Dual tasks are a common phenomenon in everyday life. In dual-task contexts, we perform two component tasks in temporal overlap, which usually results in impaired performance in one or both of these component tasks relative to single-task contexts. Numerous studies have examined dual-task interference at the level of response selection, but only few studies addressed the cognitive representation of a dual task and the cognitive mechanisms controlling these representations. The present review outlines recent empirical findings and theoretical developments concerning these two issues. In detail, the review focuses on different components of a cognitive dual-task representation, including the representation of component-task specific information (i.e., information about the goal and stimulus-response mapping of a component task), the representation of component-task order information (i.e., information about the order in which the component tasks have to executed), and the representation of dual-task identity information (i.e., information about which two component tasks have to be performed). A particular emphasis is placed on the cognitive representation of dual-task identity information, which is examined in a recent research line employing the task-pair switching logic as an empirical approach. By conceptualizing a dual-task representation as a hierarchical multi-component representation, the review integrates the research line on the cognitive representation of dual-task identity information with those on the representation of component-task specific information and of component-task order information. Based on this conceptualization, the review provides a new theoretical contribution to dual-task research and highlights an integrative perspective on the different components of cognitive dual-task representations.
RESUMO
When the performance of two tasks overlaps in time, performance impairments in one or both tasks are common. Various theoretical explanations for how component tasks are controlled in dual-task situations have been advanced. However, less attention has been paid to the issue of how two temporally overlapping tasks are appropriately coordinated in terms of their order. The current study focuses on two specific aspects of this task-order coordination: (1) the potential effects of practice on task-order coordination performance and (2) its relationships with cognitive meta-control mechanisms that adjust this coordination. These aspects were investigated in a visual-auditory dual-task combination with randomly changing task orders across trials after four sessions of dual-task practice (N = 24) and single-task practice (N = 24). The results demonstrated that task-order coordination improves during dual-task practice, and in contrast to the effects of single-task practice. Practice, on the other hand, did not show substantial evidence of an effect on the adjustment of task-order coordination. This practice-related dissociation is consistent with the assumption that (1) task-order coordination and (2) its sequential adjustment are separable sets of processes.
RESUMO
Extensive practice can significantly reduce dual-task costs (i.e., impaired performance under dual-task conditions compared with single-task conditions) and, thus, improve dual-task performance. Among others, these practice effects are attributed to an optimization of executive function skills that are necessary for coordinating tasks that overlap in time. In detail, this optimization of dual-task coordination skills is associated with the efficient instantiation of component task information in working memory at the onset of a dual-task trial. In the present paper, we review empirical findings on three critical predictions of this memory hypothesis. These predictions concern (1) the preconditions for the acquisition and transfer of coordination skills due to practice, (2) the role of task complexity and difficulty, and (3) the impact of age-related decline in working memory capacity on dual-task optimization.
RESUMO
Cognitive-motor interactions in speech production have a strong theoretical basis. However, majority of the existing literature has primarily focused on subjective and objective measures related to speech and not voice. This systematic review gathered evidence on the potential relationship between cognitive load and voice production. A search of five databases, website, citation review, and author search were completed in a sequential order to find published and unpublished literature from 1992 to 2022 using a combination of search terms including voice, cognitive load/demand/effort/flexibility, dual task, and speech production/motor. Studies for which the primary dependent variables were linguistic, or speech measures were included if voice acoustics was also measured and described. A final sample of nine articles were identified as meeting inclusion criteria: completed between 1992 and 2022, healthy adults (18+), and American English speakers. The review indicated that existing literature on the influence of cognitive load on voice production is limited. Acoustic measures, such as fundamental frequency, sound pressure level, and cepstral peak prominence, do not show consistent patterns of change with an increase in cognitive load. It is likely that the inconsistencies in the speech or cognitive task type and measurement of individual reaction to cognitive load changes may have led to these varied results. Further research using a range/continuum of cognitive tasks varying in load/difficulty level and physiological measurements is warranted to understand the underlying mechanisms of behavioral performance with implications for clinical voice assessment and rehabilitation.