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Background: Verbal fluency tasks are routinely used in clinical assessment and research studies of aphasia. People with aphasia produce fewer items in verbal fluency tasks. It remains unclear if their output is limited solely by their lexical difficulties and/or has a basis in their executive control abilities. Recent research has illustrated that detailed characterization of verbal fluency performance using temporal characteristics of words retrieved, clustering and switching, and pause durations, along with separate measures of executive control stands to inform our understanding of the lexical and cognitive underpinnings of verbal fluency in aphasia. Aims: To determine the locus of the verbal fluency difficulties in aphasia, we compared semantic and letter fluency trials between people with aphasia and healthy control participants using a wide range of variables to capture the performance between the two groups. The groups were also tested on separate measures of executive control to determine the relationship amongst these tasks and fluency performance. Methods & Procedures: Semantic (animal) and letter (F, A, S) fluency data for 60s trials were collected from 14 people with aphasia (PWA) and 24 healthy adult controls (HC). Variables, such as number of correct responses, clustering and switching analyses, were performed along with temporal measures of the retrieved words (response latencies) and pause durations. Participants performed executive control tasks to measure inhibitory control, mental‐set shifting and memory span. Outcomes & Results: Compared with HC, PWA produced fewer correct responses, showed greater difficulty with the letter fluency condition, were slower in getting started with the trials, showed slower retrieval times as noted in within‐ and between‐cluster pause durations, and switched less often. Despite these retrieval difficulties, PWA showed a similar decline in the rate of recall to HC, and had similar cluster size. Executive control measures correlated primarily with the letter fluency variables: mostly for PWA and in one instance for HC. Conclusions & Implications: Poorer performance for PWA is a combination of difficulties in both the lexical and executive components of the verbal fluency task. Our findings highlight the importance of detailed characterization of fluency performance in deciphering the underlying mechanism of retrieval difficulties in aphasia, and illustrate the importance of using letter fluency trials to tap into executive control processes. WHAT THIS PAPER ADDS: What is already known on the subject: PWA typically show impaired performance in verbal fluency tasks. It is debated whether this impaired performance is a result of their lexical difficulties or executive control difficulties, or a combination of both. This debate continues because previous studies have mostly used semantic fluency condition without including letter fluency condition; used a limited range of variables (e.g., number of correct responses); and not included separate executive control measures to explain the performance pattern in aphasia. This research addresses these outstanding issues to determine the specific contribution of lexical and executive control processes in verbal fluency in aphasia by including: both semantic and letter fluency conditions; a wide range of variables to identify the relative contribution of lexical and executive control mechanisms; and independent measures of executive control. What this paper adds to existing knowledge: Using the multidimensional analysis approach for verbal fluency performance from both semantic and letter fluency conditions, this is the first study to systematically demonstrate that PWA had difficulties in both lexical and executive control components of the task. At the individual level, PWA had greater difficulty on the letter fluency condition compared with semantic fluency. We observed significant correlations between the executive control measures and verbal fluency measures primarily for the letter fluency condition. This research makes a significant contribution to our understanding of lexical and executive control aspects in word production in aphasia. What are the potential or actual clinical implications of this work?: From a clinical perspective, this research highlights the importance of using a full range of verbal fluency and executive control measures to tap into the lexical as well as executive control abilities of PWA, and also the utility of using letter fluency to tap into the executive control processes in PWA. [ABSTRACT FROM AUTHOR]

Young children spend a lot of time at home, yet there is little empirical research on how they spend that time and how it relates to developmental outcomes. Prior research suggests less‐structured time—where children practice making choices and setting goals—may develop self‐directed executive function in 6‐year‐olds. But less‐structured time may be related to executive function for other reasons—for example, because it provides opportunities to acquire conceptual knowledge relevant to using executive function on tasks. We thus tested the possibility that less‐structured time is also related to younger children's externally cued executive function. In this remote online study, caregivers of 93 3‐ to 5‐year‐olds indicated the amount of time their child was typically spending in various activities while at home during the early phase of the COVID‐19 pandemic. Activities were categorized as structured (primarily lessons with specific goals defined by adults or an app), less‐structured (wide range of activities permitting choice and interaction with caregiver), passive (e.g., watching TV or videos), and primarily physical (e.g., bike riding). Children's externally cued executive function was assessed via the Dimensional Change Card Sort (DCCS). Time and variety in less‐structured activities were related to successful switching on the DCCS, controlling for age, family income, caregiver education, and verbal knowledge. Caregivers were more involved in less‐structured versus structured activities. Caregiver ratings of children's temperament were related to how children's time was spent. These findings suggest several new avenues for studying young children's activities at home and their relations with developmental outcomes. A video abstract of this article can be viewed at https://youtu.be/3aGmpSnjuCs [ABSTRACT FROM AUTHOR]