Pascal Sockeel

The Lille apathy rating scale (LARS), a new instrument for detecting and quantifying apathy: validation in Parkinson’s disease

Background: Apathy is usually defined as reduced interest and participation in various activities. It is a frequent consequence of neurological and psychiatric disorders. Although various scoring methods have been proposed, there is a lack of validated, standardised instruments for detecting apathy and assessing its severity. Objective: To develop an apathy rating scale using a structured standardised interview capable of distinguishing between the condition’s various features. Methods: The Lille Apathy Rating Scale (LARS) is based on a structured interview. It includes 33 items, divided into nine domains. Responses are scored on a dichotomous scale. The participants used to validate the scale consisted of 159 patients with probable Parkinson’s disease and 58 healthy control subjects. The Marin Apathy Scale, the Montgomery and Asberg Depression Rating Scale, and the Mattis Dementia Rating Scale were also administered. Results: Principal component analysis showed that the LARS probed a single construct which forms the root of an oblique factor structure reflecting four dimensions: intellectual curiosity, self awareness, emotion, and action initiation. The main psychometric properties of the LARS (internal consistency, inter-rater and test-retest reliability) were satisfactory. Concurrent validity was evaluated by reference to the Marin scale and to judgements provided by expert clinicians. Conclusions: Standard validity indices showed that the LARS is sensitive and capable of distinguishing between apathy and depression. As a screening tool, the scale is able to support dichotomous judgements accurately and, when greater measurement sensitivity is required, also determine the severity of apathy within a four category classification.

Characteristics of apathy in Parkinson's disease

The objective of this study was to use the Lille Apathy Rating Scale to assess apathy in a large population of Parkinsons disease (PD) patients and identify several different apathy profiles. One hundred fifty‐nine patients with probable PD and 58 healthy controls participated in the study. Apathy was assessed using the Lille Apathy Rating Scale. Motor, cognitive, and depressive symptoms were rated on standardized scales. Data were analyzed using linear regression and multivariate analyses of variance. Thirty‐two percent of the PD patients were classified as apathetic. Apathy was more frequent in patients with dementia. The four apathy dimensions contributed differently to the overall severity of the apathetic condition. Action initiation and intellectual curiosity had a marked influence. Linear regression analysis revealed that the apathy level was mainly determined by cognitive impairment, not associated with the severity of motor symptoms, and only associated with the apathy subcomponent of the Montgomery and Asberg Depression Rating Scale. Apathy is highly prevalent in PD patients. Apathy profiles vary according to the clinical presentation of PD. The high prevalence of apathy in PD suggests the involvement of frontal–subcortical circuits. Although the neurochemical substrate of apathy remains poorly characterized, the strong link between apathy and cognitive impairment observed in several studies suggests the participation of nondopaminergic circuits.

The Lille Apathy Rating Scale: Validation of a caregiver-based version

Apathy is reported in 16.5% to 70% of Parkinsons disease (PD) patients. Our recently developed Lille Apathy Rating Scale (LARS) has been specifically validated for patient‐based assessment of apathy in PD. The aim of the present study was to validate a caregiver‐based version of the LARS. Sixty consecutive PD patients and their respective caregivers participated in the study. An informant‐based version of the LARS (LARS‐i) was developed to rate apathy via a caregiver‐based structured interview. Apathy was also assessed in a patient‐based interview using the LARS and the informant‐ and clinician‐rated versions of the Apathy Evaluation Scale (AES). Cronbachs alpha and standardized alpha coefficients were 0.872 and 0.877, respectively, and the split‐half reliability was 0.901 (revealing good internal consistency). The test‐retest and inter‐rater reliability values were 0.960 and 0.996, respectively. Criterion‐related validity (according to an independent, expert diagnosis) was good. Scores on the LARS and the LARS‐i were highly correlated. However, apathy was rated significantly more severely by the caregiver than by the patient. This difference was significantly higher for demented than nondemented PD patients. The LARS‐i was seen to have excellent psychometric properties and appears to be valid for use in PD with respect to the patient‐based LARS and the informant‐ and clinician‐rated versions of the AES.

Route Learning and Shortcut Performance in Adults with Intellectual Disability: A Study with Virtual Environments

The ability to learn routes though a virtual environment (VE) and to make a novel shortcut between two locations was assessed in 18 adults with intellectual disability and 18 adults without intellectual disability matched on chronological age. Participants explored two routes (A ⇔ B and A ⇔ C) until they reached a learning criterion. Then, they were placed at B and were asked to find the shortest way to C (B ⇔ C, five trials). Participants in both groups could learn the routes, but most of the participants with intellectual disability could not find the shortest route between B and C. However, the results also revealed important individual differences within the intellectual disability group, with some participants exhibiting more efficient wayfinding behaviour than others. Individuals with intellectual disability may differ in the kind of spatial knowledge they extract from the environment and/or in the strategy they use to learn routes.

Wayfinding Behaviour in Down Syndrome: A Study with Virtual Environments.

The aim of this study was to assess wayfinding abilities in individuals with Down syndrome (DS). The ability to learn routes though a virtual environment (VE) and to make a novel shortcut between two locations was assessed in individuals with DS (N=10) and control participants individually matched on mental age (MA) or chronological age (CA). The results showed that most of the participants with DS were able to learn routes through the VE, even though they needed more trials than the CA controls to reach the learning criterion. However, they did not show flexible wayfinding behaviour because they were unable to find a shortcut between two known locations (unlike the CA controls). The results suggest that most individuals with DS can acquire knowledge about specific routes, but are unable to integrate that knowledge into a configurational understanding of the environment.

The development of route learning in Down syndrome, Williams syndrome and typical development: investigations with virtual environments

The ability to navigate new environments has a significant impact on the daily life and independence of people with learning difficulties. The aims of this study were to investigate the development of route learning in Down syndrome (N = 50), Williams syndrome (N = 19), and typically developing children between 5 and 11 years old (N = 108); to investigate use of landmarks; and to relate cognitive functions to route-learning ability in these groups. Overall, measures of attention and long-term memory were strongly associated with route learning, even once non-verbal ability was controlled for. All of the groups, including 5- to 6-year-old TD children, demonstrated the ability to make use of all landmark types to aid route learning; those near junctions, those further from junctions, and also distant landmarks (e.g. church spire, radio mast). Individuals with WS performed better than a matched subset of TD children on more difficult routes; we suggest that this is supported by relatively strong visual feature recognition in the disorder. Participants with DS who had relatively high levels of non-verbal ability performed at a similar level to TD participants.

Short-term memory, executive control, and children’s route learning

The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11years and to relate route-learning performance to the components of Baddeleys model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and visuospatial long-term memory; the route-learning task was conducted using a maze in a virtual environment. In contrast to previous research, correlations were found between both visuospatial and verbal memory tasks-the Corsi task, short-term pattern span, digit span, and visuospatial long-term memory-and route-learning performance. However, further analyses indicated that these relationships were mediated by executive control demands that were common to the tasks, with long-term memory explaining additional unique variance in route learning.

Assessing apathy in everyday clinical practice with the short-form Lille Apathy Rating Scale

Apathy is an invalidating behavioral disorder that must always be screened for and assessed in patients with Parkinsons disease (PD). The Lille Apathy Rating Scale (LARS) has been validated in several different contexts, but the lengthy administration time means that it is mostly recommended for research use. The aim of the present study was to validate a short form of the LARS for use in everyday practice.

Do individuals with intellectual disability select appropriate objects as landmarks when learning a new route

BACKGROUND The present study was aimed at investigating the selection of landmarks by individuals with intellectual disability (ID). The hypothesis was that they would be less efficient than individuals without IDs in the selection of landmarks when learning a new route. METHODS The experiment took place in a natural setting with a group of participants with ID and a group of control participants matched by chronological age. The participants were first guided along a route situated in an unfamiliar district. Then, they had to guide the experimenter along the route while pointing to all the objects and features they found useful for wayfinding. RESULTS The designated objects were categorised as a function of their landmarks properties. There were significant differences between the two groups for non-permanent landmarks, distant landmarks and non-unique landmarks. The two groups selected landmarks near intersections in the same proportions. However, the individuals with ID selected more non-unique landmarks and less textual signage than the control group at these decision points. CONCLUSION Individuals with ID seem to be less efficient than individuals without disability in landmark selection. This may limit their wayfinding abilities in their day-to-day travelling. This may also account for their difficulties in obtaining the kind of spatial knowledge which relates to the configural structure of their environment.