Delineating the neural substrates of autobiographical memory impairment in Huntington's disease.

Emerging evidence suggests that autobiographical memory (ABM) is altered in Huntington's disease (HD). While these impairments are typically attributed to frontostriatal dysfunction, the neural substrates of ABM impairment in HD remain unexplored. To this end, we assessed ABM in 30 participants with genetically confirmed HD (18 premanifest, 12 manifest) and 24 age-matched healthy controls.

Development of the Flexibility in Daily Life scale to measure multidimensional cognitive and behavioural flexibility in health and disease.

Objectives: Inflexibility of thought and behaviour is a transdiagnostic feature of many neuropsychiatric disorders and presents several empirical measurement challenges. Here, we developed and validated the Flexibility in Daily Life scale (FIDL); a novel, self-report questionnaire, which captures expressions of cognitive and behavioural flexibility in daily life and is sensitive to natural shifts in these processes across the adult lifespan.

Methods: The FIDL was developed using a deductive scale development approach, which aimed to capture common themes within the flexibility literature and across diagnoses (e.

Profiles of motivational impairment and their relationship to functional decline in frontotemporal dementia.

Motivational disturbances are pervasive in frontotemporal dementia (FTD) and impact negatively on everyday functioning. Despite mounting evidence of anhedonia in FTD, it remains unclear how such changes fit within the broader motivational symptom profile of FTD, or how anhedonia relates to functional outcomes. Here we sought to comprehensively characterize motivational disturbances in FTD and their respective relationships with functional impairment.

Establishing the link between motivational disturbances and behavioural rigidity in frontotemporal dementia.

Background: Rigid and inflexible behaviours are common in frontotemporal dementia (FTD), manifesting in compulsive pursuit of specific interests, routines, and rituals. Paradoxically, these changes occur alongside profound motivational disturbances including apathy and anhedonia. While posited to be related, no study to date has explored the link between motivational changes and behavioural rigidity in FTD.

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).

Reconciling profiles of reward-seeking versus reward-restricted behaviours in frontotemporal dementia.

This scientific commentary refers to 'The architecture of abnormal reward behaviour in dementia: multimodal hedonic phenotypes and brain substrate', by Chokesuwattanaskul (https://doi.org/10.1093/braincomms/fcad027).

Post-stroke apathy: A case series investigation of neuropsychological and lesion characteristics.

Apathy is a multi-dimensional syndrome associated with reduced initiation, executive function and emotion toward goal-directed behaviour. Affecting ∼30% of stroke patients, apathy can negatively impact rehabilitation outcomes and increase caregiver burden. However, relatively little is known about the multi-dimensional nature of post-stroke apathy and whether these dimensions map onto neuropsychological and neuroanatomical correlates.

Evidence against benefits from cognitive training and transcranial direct current stimulation in healthy older adults.

Cognitive training and brain stimulation show promise for ameliorating age-related neurocognitive decline. However, evidence for this is controversial. In a Registered Report, we investigated the effects of these interventions, where 133 older adults were allocated to four groups (left prefrontal cortex anodal transcranial direct current stimulation (tDCS) with decision-making training, and three control groups) and trained over 5 days.

Structural and functional brain correlates of theory of mind impairment post-stroke.

The ability to understand the mental states of others - also known as Theory of Mind (ToM) - is critical for normal social interactions. We combine behavioural probes with structural and functional brain imaging to provide the first comprehensive analysis of ToM deficits following stroke using the Reading the Mind in the Eyes Test (RMET). First, fMRI was used to identify the functional brain network involved in a non-clinical cohort.

Do implicit and explicit belief processing share neural substrates?

Humans rely on their ability to infer another person's mental state to understand and predict others' behavior ("theory of mind," ToM). Multiple lines of research suggest that not only are humans able to consciously process another person's belief state, but also are able to do so implicitly. Here we explored how general implicit belief states are represented in the brain, compared to those substrates involved in explicit ToM processes.