Functional re-organization of hippocampal-cortical gradients during naturalistic memory processes.

The functional organization of the hippocampus mirrors that of the cortex, changing smoothly along connectivity gradients and abruptly at inter-areal boundaries. Hippocampal-dependent cognitive processes require flexible integration of these hippocampal gradients into functionally related cortical networks. To understand the cognitive relevance of this functional embedding, we acquired fMRI data while participants viewed brief news clips, either containing or lacking recently familiarized cues. Participants were 188 healthy mid-life adults and 31 adults with mild cognitive impairment (MCI) or Alzheimer's disease (AD). We employed a recently developed technique - connectivity gradientography - to study gradually changing patterns of voxel to whole brain functional connectivity and their sudden transitions. We observed that functional connectivity gradients of the anterior hippocampus map onto connectivity gradients across the default mode network during these naturalistic stimuli. The presence of familiar cues in the news clips accentuates a stepwise transition across the boundary from the anterior to the posterior hippocampus. This functional transition is shifted in the posterior direction in the left hippocampus of individuals with MCI or AD. These findings shed new light on the functional integration of hippocampal connectivity gradients into large-scale cortical networks, how these adapt with memory context and how these change in the presence of neurodegenerative disease.

The Role of Apathy in Spontaneous Verbal and Nonverbal Behaviors: A Transdiagnostic Pilot Study in Neurodegeneration.

BACKGROUND: Apathy, characterized by a quantifiable reduction in motivation or goal-directed behavior, is a multidimensional syndrome that has been observed across many neurodegenerative diseases. OBJECTIVE: To develop a novel task measuring spontaneous action initiation (ie, a nonverbal equivalent to spontaneous speech tasks) and to investigate the association between apathy and executive functions such as the voluntary initiation of speech and actions and energization (ie, ability to initiate and sustain a response). METHOD: We compared the energization and executive functioning performance of 10 individuals with neurodegenerative disease and clinically significant apathy with that of age-matched healthy controls (HC). We also investigated the association between self-reported scores on the Apathy Evaluation Scale (AES) and performance on energization tasks. RESULTS: The individuals with apathy made significantly fewer task-related actions than the HC on the novel spontaneous action task, and their scores on the AES were negatively correlated with spontaneous task-related actions, providing preliminary evidence for the task's construct validity. In addition, the individuals with apathy performed more poorly than the HC on all of the energization tasks, regardless of task type or stimulus modality, suggesting difficulty in sustaining voluntary responding over time. Most of the tasks also correlated negatively with the AES score. However, the individuals with apathy also performed more poorly on some of the executive function tasks, particularly those involving self-monitoring. CONCLUSION: Our work presents a novel experimental task for measuring spontaneous action initiation-a key symptom of apathy-and suggests a possible contribution of apathy to neuropsychological deficits such as poor energization.

Age of Onset and Length of Survival of Queensland Patients with Amyotrophic Lateral Sclerosis: Details of Subjects with Early Onset and Subjects with Long Survival.

INTRODUCTION: The aims of the study were to document the characteristics of amyotrophic lateral sclerosis (ALS) patients in Queensland, to examine factors influencing age of onset, and survival, and to study those with early-onset (<45 years) disease and those with long (>5 years) survival. METHODS: We studied subjects seen at the ALS Clinic at the Royal Brisbane and Women's Hospital. We recorded sex, age of onset, region of onset, length of survival, presence of family history, type of disease, and evidence of cognitive involvement. We analysed the influence of these features on age of onset and survival. We analysed the features of patients with early onset of disease and patients with long survival. RESULTS: There were 855 ALS patients (505 males) in the cohort. The age of onset was lower in males than females, in patients with a family history of ALS compared to those without, and in patients with spinal onset compared to bulbar onset. Early-onset disease was seen in 10% of patients, and had a greater proportion of males, spinal onset, and classical ALS phenotype compared to late-onset disease. Survival was shorter in females, in patients with bulbar onset, and in patients with classical ALS. Long survival was seen in 18% of patients. Patients with long survival had younger age of onset, greater proportion of males, spinal onset, and fewer patients with classical ALS. CONCLUSION: Our study confirms that ALS is more prevalent in males and that spinal onset is more common than bulbar onset. Males have earlier onset but longer survival. We found that overall, patients with classical ALS have worse survival than ALS variants, but some patients who were considered to have classical ALS had long survival. This study confirms the similarity of ALS in our region to ALS in other geographical regions.

Verbal Adynamia and Conceptualization in Partial Rhombencephalosynapsis and Corpus Callosum Dysgenesis.

Verbal adynamia is characterized by markedly reduced spontaneous speech that is not attributable to a core language deficit such as impaired naming, reading, repetition, or comprehension. In some cases, verbal adynamia is severe enough to be considered dynamic aphasia. We report the case of a 40-year-old, left-handed, male native English speaker who presented with partial rhombencephalosynapsis, corpus callosum dysgenesis, and a language profile that is consistent with verbal adynamia, or subclinical dynamic aphasia, possibly underpinned by difficulties selecting and generating ideas for expression. This case is only the second investigation of dynamic aphasia in an individual with a congenital brain malformation. It is also the first detailed neuropsychological report of an adult with partial rhombencephalosynapsis and corpus callosum dysgenesis, and the only known case of superior intellectual abilities in this context.

Subthalamic deep brain stimulation identifies frontal networks supporting initiation, inhibition and strategy use in Parkinson's disease.

Initiation and inhibition are executive functions whose disruption in Parkinson's disease impacts substantially on everyday activities. Management of Parkinson's disease with subthalamic deep brain stimulation (DBS) modifies initiation and inhibition, with prior work suggesting that these effects may be mediated via the connectivity of the subthalamic nucleus (STN) with the frontal cortex. Here, we employed high-resolution structural neuroimaging to investigate the variability in initiation, inhibition and strategy use in a cohort of twenty-five (ten females, mean age 62.5, mean Hoehn and Yahr stage 2.5) participants undertaking subthalamic DBS for Parkinson's disease. Neuropsychological assessment of initiation and inhibition was performed preoperatively and at six months postoperatively. We first reconstructed the preoperative connectivity of the STN with a frontal network of anterior and superior medial cortical regions. We then modelled the postoperative site of subthalamic stimulation and reconstructed the connectivity of the stimulation field within this same network. We found that, at both pre- and postoperative intervals, inter-individual variability in inhibition and initiation were strongly associated with structural network connectivity. Measures of subcortical atrophy and local stimulation effects did not play a significant role. Preoperatively, we replicated prior work, including a role for the right inferior frontal gyrus in inhibition and strategy use, as well as the left inferior frontal gyrus in tasks requiring selection under conditions of maintained inhibition. Postoperatively, greater connectivity of the stimulation field with right anterior cortical regions was associated with greater rule violations and suppression errors, supporting prior work implicating right-hemispheric STN stimulation in disinhibition. Our findings suggest that, in Parkinson's disease, connectivity of the frontal cortex with the STN is an important mediator of individual variability in initiation and inhibition,. Personalised information on brain network architecture could guide individualised brain circuit manipulation to minimise neuropsychological disruption after STN-DBS.

Idea Formulation for Spoken Language Production: The Interface of Cognition and Language.

BACKGROUND: Language and communication are fundamental to the human experience, and, traditionally, spoken language is studied as an isolated skill. However, before propositional language (i.e., spontaneous, voluntary, novel speech) can be produced, propositional content or 'ideas' must be formulated. OBJECTIVE: This review highlights the role of broader cognitive processes, particularly 'executive attention', in the formulation of propositional content (i.e., 'ideas') for propositional language production. CONCLUSIONS: Several key lines of evidence converge to suggest that the formulation of ideas for propositional language production draws on executive attentional processes. Larger-scale clinical research has demonstrated a link between attentional processes and language, while detailed case studies of neurological patients have elucidated specific idea formulation mechanisms relating to the generation, selection and sequencing of ideas for expression. Furthermore, executive attentional processes have been implicated in the generation of ideas for propositional language production. Finally, neuroimaging studies suggest that a widely distributed network of brain regions, including parts of the prefrontal and parietal cortices, supports propositional language production. IMPLICATIONS: Theoretically driven experimental research studies investigating mechanisms involved in the formulation of ideas are lacking. We suggest that novel experimental approaches are needed to define the contribution of executive attentional processes to idea formulation, from which comprehensive models of spoken language production can be developed. Clinically, propositional language impairments should be considered in the context of broader executive attentional deficits.

Callosal agenesis and congenital mirror movements: outcomes associated with DCC mutations.

Pathogenic variants in the gene encoding deleted in colorectal cancer (DCC) are the first genetic cause of isolated agenesis of the corpus callosum (ACC). Here we present the detailed neurological, brain magnetic resonance imaging (MRI), and neuropsychological characteristics of 12 individuals from three families with pathogenic variants in DCC (aged 8-50y), who showed ACC and mirror movements (n=5), mirror movements only (n=2), ACC only (n=3), or neither ACC nor mirror movements (n=2). There was heterogeneity in the neurological and neuroimaging features on brain MRI, and performance across neuropsychological domains ranged from extremely low (impaired) to within normal limits (average). Our findings show that ACC and/or mirror movements are associated with low functioning in select neuropsychological domains and a DCC pathogenic variant alone is not sufficient to explain the disability. WHAT THIS PAPER ADDS: Neuropsychological impairment severity is related to presence of mirror movements and/or agenesis of the corpus callosum. A DCC pathogenic variant in isolation is associated with the best prognosis.

Novel cognitive insights from the first year after bi-thalamic infarct.

Neuropsychological consequences of bi-thalamic damage are scarcely known. This case study documents cognitive (in particular memory and executive) functioning in a man with a medial bi-thalamic infarct in the first year (8 and 12 months) post injury. NG showed persistent memory (including autobiographical) impairment, but improved executive functions at one year post injury. On a response inhibition task his speed of response improved but his ability to inhibit a "prepotent" automatic response declined, corresponding to an increase in behavioral disinhibition. Despite this, he showed intact performances on several social cognition tasks. This case contributes to our understanding of the role of the thalamus in mediating retrograde memory, executive, and social cognition functions.

Executive Dysfunction After Fourth-Ventricle Epidermoid Cyst Resection.

Intracranial epidermoid cysts are rare, comprising 0.2% to 1.8% of all primary intracranial expanding lesions, of which <5% occur within the fourth ventricle. Epidermoid cysts are frequently congenital, and patients often present in the fourth decade of life. These cysts produce symptoms as a result of mass effect on surrounding structures, most commonly the cerebellum and cranial nerves. Symptoms can include hearing impairment, trigeminal neuralgia (severe facial pain), facial tics, headaches, double vision, and facial palsy. However, no research has focused on the neuropsychological effects on a patient after surgical resection of these cysts. This case report presents the cognitive profile of a woman after resection of an epidermoid cyst in the fourth ventricle. The 49-year-old patient underwent neuropsychological assessment after removal of the cyst, completing a comprehensive set of cognitive tests of estimated premorbid intelligence, attention, memory, social cognition, language, visual perception, and executive functioning. Test results indicated executive dysfunction and reduced visuospatial memory in the acute stage after surgical removal of the epidermoid cyst. These findings suggest that cognitive deficits can occur after resection of space-occupying lesions in brain regions not typically associated with cognition. To our knowledge, this is the first report of the neuropsychological consequences of surgical removal of a congenital epidermoid cyst in the fourth ventricle. An understanding of the neuropsychological sequelae of this rare cerebral cyst will allow patients, families, and health professionals to better anticipate and manage postoperative difficulties.

Verbal Initiation, Suppression, and Strategy Use and the Relationship with Clinical Symptoms in Schizophrenia.

OBJECTIVES: Individuals with schizophrenia have difficulties on measures of executive functioning such as initiation and suppression of responses and strategy development and implementation. The current study thoroughly examines performance on the Hayling Sentence Completion Test (HSCT) in individuals with schizophrenia, introducing novel analyses based on initiation errors and strategy use, and association with lifetime clinical symptoms. METHODS: The HSCT was administered to individuals with schizophrenia (N=77) and age- and sex-matched healthy controls (N=45), along with background cognitive tests. The standard HSCT clinical measures (initiation response time, suppression response time, suppression errors), composite initiation and suppression error scores, and strategy-based responses were calculated. Lifetime clinical symptoms [formal thought disorder (FTD), positive, negative] were calculated using the Lifetime Dimensions of Psychosis Scale. RESULTS: After controlling for baseline cognitive differences, individuals with schizophrenia were significantly impaired on the suppression response time and suppression error scales. For the novel analyses, individuals with schizophrenia produced a greater number of initiation errors and subtly wrong errors, and produced fewer responses indicative of developing an appropriate strategy. Strategy use was negatively correlated with FTD symptoms in individuals with schizophrenia. CONCLUSIONS: The current study provides further evidence for deficits in the initiation and suppression of verbal responses in individuals with schizophrenia. Moreover, an inability to attain a strategy at least partly contributes to increased semantically connected errors when attempting to suppress responses. The association between strategy use and FTD points to the involvement of executive deficits in disorganized speech in schizophrenia. (JINS, 2016, 22, 735-743).

Cognitive and Social Functioning Deficits after Anti-N-Methyl-D-Aspartate Receptor Encephalitis: An Exploratory Case Series.

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently described life-threatening autoimmune disorder associated with a characteristic multi-stage neuropsychiatric syndrome. Although it is known that the majority of patients experience neuropsychological disturbance post-treatment, some aspects of the cognitive profile remain unclear. METHODS: This study sought to investigate patterns of cognitive functioning in a sample of anti-NMDAR encephalitis patients. Seven (6F:1M; mean age, 26.4 years; range, 16-37 years) treated patients completed a comprehensive set of neurocognitive and social functioning measures. Performance was analyzed using normative data (where available), and comparison with matched controls (10F:4M; mean age, 25.8 years; range, 16-38 years). RESULTS: Individual cognitive profiles ranged from within normal limits to extensive dysfunction. Relative to controls, the patient group's performance was affected in the domains of verbal/ visual memory, working memory, attention, processing speed, executive functioning, and social cognition. The patient group also reported significantly higher levels of anxiety compared to controls. CONCLUSIONS: These results add to the accumulating evidence that neurocognitive deficits, consistent with the distribution and functions of the NMDAR system can persist during recovery from anti-NMDAR encephalitis. This is the first study to provide evidence of performance decrements on measures of social cognition, including some involving theory of mind. (JINS, 2016, 22, 828-838).

Verbal suppression and strategy use: a role for the right lateral prefrontal cortex?

Verbal initiation, suppression and strategy generation/use are cognitive processes widely held to be supported by the frontal cortex. The Hayling Test was designed to tap these cognitive processes within the same sentence completion task. There are few studies specifically investigating the neural correlates of the Hayling Test but it has been primarily used to detect frontal lobe damage. This study investigates the components of the Hayling Test in a large sample of patients with unselected focal frontal (n = 60) and posterior (n = 30) lesions. Patients and controls (n = 40) matched for education, age and sex were administered the Hayling Test as well as background cognitive tests. The standard Hayling Test clinical measures (initiation response time, suppression response time, suppression errors and overall score), composite errors scores and strategy-based responses were calculated. Lesions were analysed by classical frontal/posterior subdivisions as well as a finer-grained frontal localization method and a specific contrast method that is somewhat analogous to voxel-based lesion mapping methods. Thus, patients with right lateral, left lateral and superior medial lesions were compared to controls and patients with right lateral lesions were compared to all other patients. The results show that all four standard Hayling Test clinical measures are sensitive to frontal lobe damage although only the suppression error and overall scores were specific to the frontal region. Although all frontal patients produced blatant suppression errors, a specific right lateral frontal effect was revealed for producing errors that were subtly wrong. In addition, frontal patients overall produced fewer correct responses indicative of developing an appropriate strategy but only the right lateral group showed a significant deficit. This problem in strategy attainment and implementation could explain, at least in part, the suppression error impairment. Contrary to previous studies there was no specific frontal effect for verbal initiation. Overall, our results support a role for the right lateral frontal region in verbal suppression and, for the first time, in strategy generation/use.

"My Mind Is Doing It All": No "Brake" to Stop Speech Generation in Jargon Aphasia.

OBJECTIVE: To study whether pressure of speech in jargon aphasia arises out of disturbances to core language or executive processes, or at the intersection of conceptual preparation. BACKGROUND: Conceptual preparation mechanisms for speech have not been well studied. Several mechanisms have been proposed for jargon aphasia, a fluent, well-articulated, logorrheic propositional speech that is almost incomprehensible. METHODS: We studied the vast quantity of jargon speech produced by patient J.A., who had suffered an infarct after the clipping of a middle cerebral artery aneurysm. We gave J.A. baseline cognitive tests and experimental word- and sentence-generation tasks that we had designed for patients with dynamic aphasia, a severely reduced but otherwise fairly normal propositional speech thought to result from deficits in conceptual preparation. RESULTS: J.A. had cognitive dysfunction, including executive difficulties, and a language profile characterized by poor repetition and naming in the context of relatively intact single-word comprehension. J.A.'s spontaneous speech was fluent but jargon. He had no difficulty generating sentences; in contrast to dynamic aphasia, his sentences were largely meaningless and not significantly affected by stimulus constraint level. CONCLUSIONS: This patient with jargon aphasia highlights that voluminous speech output can arise from disturbances of both language and executive functions. Our previous studies have identified three conceptual preparation mechanisms for speech: generation of novel thoughts, their sequencing, and selection. This study raises the possibility that a "brake" to stop message generation may be a fourth conceptual preparation mechanism behind the pressure of speech characteristic of jargon aphasia.

Propositional speech in unselected stroke: The effect of genre and external support.

Distinguished from nominal language, propositional language generation refers to the spontaneous and voluntary aspect of language that introduces novel concepts to a specific context. Propositional language can be impaired in a range of neurological disorders, including stroke, despite well-preserved nominal language. Although external support can increase speech rate in patients with reduced propositional speech, no specific investigation of propositional speech has been carried out in unselected stroke patients. The current study investigated propositional language in an unselected post-acute stroke group (N = 18) with mild cognitive impairment and prominent executive dysfunction, but without significant aphasia. Specifically, we investigated whether genre or external support affected the number of words, sentences, and novel ideas produced, compared to healthy controls (N = 27). Results showed that discourse genre was not associated with differential performances. By contrast, speech quantity increased without external support although, for stroke patients, speech novelty decreased. Overall, the novelty deficit in unselected stroke patients highlights the importance of assessing cognition and propositional speech. Our findings suggest that for stroke patients with mild cognitive deficits, including executive dysfunction, introducing external support improved speech quality but not quantity. Implications for both assessment and rehabilitation of social communication are discussed.

Interference and attentional switching in aging.

OBJECTIVE: Diffusion decision modeling (DDM) is a validated cognitive modeling method that has been used to provide insights into why older adults are slower than younger adults on a wide variety of cognitive tasks. DDM results have shown that increased processing time, caution, and sensorimotor factors have explained most of this slowing. Enhanced attentional processing of irrelevant information by older adults has also been reported in DDM studies but not explicitly studied. This enhanced processing of interference has been attributed to a motivational goal-directed decision to minimize errors by increasing accumulation of information (i.e., caution) rather than neurocognitive changes associated with aging. No DDM study has explicitly investigated interference and aging by comparing single task and dual performance within the framework of attentional control to explore more fully what and how attentional processes are involved. Our study attempts to fill these gaps. METHOD: We used a choice response time (RT) task of attentional switching with and without interference and applied the EZ-diffusion model on the data of 117 healthy younger and older adults aged 18-87. RESULTS: Repeated mixed-measures analyses of variance of DDM parameters found that longer nondecision time was the main driver for longer RTs for older adults on both attentional switch tasks, but more prominently on the attentional switch trials of the dual task. CONCLUSIONS: Processing interference before the decision to switch attention was the main driver of increased RTs for older adults. Rather than motivational goal-directed factors for error minimization (i.e., caution), findings supported neurocognitive and inhibition deficit explanations. Future DDM studies into cognition and aging could consider how difficulties inhibiting interference impacts on the cognitive processes under investigation and whether the concept of caution is applicable. Findings raise functional considerations for older adults on visually oriented tasks that require attentional switching (e.g., work vs. driving). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Hayling and stroop tests tap dissociable deficits and network-level neural correlates.

Although many executive function screens have been developed, it is not yet clear whether these assessments are equally effective in detecting post-stroke deficits of initiation and inhibition. This study presents a comparative analysis of the Stroop and Hayling tests aiming to evaluate whether these tests measure the same underlying cognitive functions and to identify the neural correlates of the deficits detected by both tasks. Sixty six stroke survivors and 70 healthy ageing controls completed the Hayling and Stroop tests. Stroke patients were found to exhibit qualitative performance differences across analogous Stroop and Hayling Test metrics intended to tap initiation and inhibition. The Stroop test was found to have high specificity to abnormal performance, but low sensitivity relative to the Hayling Test. Minimal overlap was present between the network-level correlates of analogous Stroop and Hayling Test metrics. Hayling Task strategy use metrics were significantly associated with distinct patterns of disconnection in stroke survivors, providing novel insight into the neural correlates of fine-grained behavioural patterns. Overall, these findings strongly suggest that the functions tapped by the Stroop and Hayling Test are both behaviourally and anatomically dissociable. The Hayling Test was found to offer improved sensitivity and detail relative to the Stroop test. This novel demonstration of the Hayling Test within the stroke population suggests that this task represents an effective measure for quantifying post-stroke initiation and inhibition deficits.

The brief executive language screen: sensitivity and specificity in acute to early sub-acute stroke.

INTRODUCTION: Propositional language and underlying executive functions can be impaired post-stroke and affect communication and quality of life. Current stroke screening tools are largely tailored to patients with aphasia, being either non-verbal or focussed on core language skills such as naming and repetition. The Brief Executive Language Screening Test (BELS) is a newly developed cognitive screening tool that assesses memory, oral apraxia, core language, as well as propositional language and associated executive functions that can be impacted and overlooked in stroke patients without aphasia. This study examines BELS sensitivity and specificity, and performance in acute to early sub-acute stroke relative to controls. METHOD: Cross-sectional BELS data from 88 acute left and right hemisphere stroke patients (within 7 weeks of stroke) and 116 age-matched healthy controls were compared using independent samples t-tests. ROC Curve Analysis was performed to determine a cutoff score for the BELS. RESULTS: Left and right stroke patients were reduced on all propositional language subtests, and executive function subtests of inhibition, strategy, and selection. Differences were also observed for Oral Apraxia, Naming, and Memory. By contrast, Word Comprehension and Repetition, and Sentence Completion Initiation (after corrections applied) did not differ between groups. A total BELS score of 79.25/100 was highly sensitive (.89) and specific (.89) when classifying stroke patients and healthy controls. CONCLUSION: The BELS is brief, sensitive, suitable for bedside administration, and can aid in detection and rehabilitation of subtle executive language impairments. This in turn will help improve relationships and quality of life post-stroke.

Sensitivity and specificity of the ECAS in identifying executive function and social cognition deficits in MND.

Objective: Motor neurone disease [MND] encompasses broad cognitive impairments, which are not fully captured by most screening tools. This study evaluated the specificity and sensitivity of the Edinburgh Cognitive and Behavioral ALS Screen [ECAS] in detecting impairments in executive function and social cognition. Methods: Participants (MND = 64; Healthy Controls = 45) completed the ECAS and standard neuropsychology tests of executive function and social cognition. Sensitivity and specificity of the ECAS were assessed at three levels (ALS-Specific score, executive function domain score, individual subtests: social cognition, inhibition, working memory, alternation). Results: MND patients were impaired on standard social cognition, initiation, visuomotor alternation, and verbal learning tests but not on inhibition or working memory tests, relative to controls. ECAS results revealed that the ALS-Specific score was high in specificity but low-to-moderately sensitive in identifying social cognition, inhibition, and working memory deficits, and that both sensitivity and specificity were high for identifying alternation deficits. The ECAS executive function domain score was high in specificity but poor in sensitivity for all four executive function domain subtests. The individual ECAS subtests were highly specific with good sensitivity, but the social cognition subtest lacked sensitivity. Conclusions: Impairments in social cognition may go undetected when using the ECAS as a screening tool. Thus, social cognition may need to be considered as a standalone component, distinct from the other executive functions. In addition, the test itself may need to be adjusted to encompass other aspects of social cognition that are affected in MND.Key messagesCognitive screening tools are key to detect cognitive changes in MND, with the domains most affected being executive functions, language, and social cognition.The ECAS measure, developed for MND, has good specificity but lacks sensitivity to impairments in social cognition.Clinical implications are that cognitive impairments in social cognition may not be identified in MND patients by the ECAS.Adjustment to the ECAS cognitive screening tool widely-used in MND is suggested.

Verbal and nonverbal fluency in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a multi-system disorder that commonly affects cognition and behaviour. Verbal fluency impairments are consistently reported in ALS patients, and we aimed to investigate whether this deficit extends beyond the verbal domain. We further aimed to determine whether deficits are underpinned by a primary intrinsic response generation impairment (i.e., a global reduction across tasks), potentially related to apathy, or an inability to maintain responding over time (i.e., a 'drop off' pattern). Twenty-two ALS patients and 21 demographically-matched controls completed verbal and nonverbal fluency tasks (phonemic/semantic word fluency, design fluency, gesture fluency and ideational fluency), requiring the generation of responses over a specified time period. Fluency performance was analysed in terms of the overall number of novel items produced, as well as the number of items produced in the first 'initiation' and the remaining 'maintenance' time periods. ALS patients' overall performance was not globally reduced across tasks. Patients were impaired only on meaningful gesture fluency, which requires the generation of gestures that communicate meaning (e.g., waving). On phonemic fluency, ALS patients showed a 'drop off' pattern of performance, where they had difficulty maintaining responding over time, but this pattern was not evident on the other fluency tasks. Apathy did not appear to be related to fluency performance. The selective meaningful gesture fluency deficit, in the context of preserved meaningless gesture fluency, highlights that the retrieval of action knowledge may be weakened in early ALS.