Humor comprehension in primary-school-aged children with epilepsy

The present research aimed to compare humor comprehension in primary-school-aged healthy children and children suffering from epilepsy, and to examine whether the peculiarities in humor perception of preschool children with epilepsy that were found in Suits’s (2007) research (e.g. dichotomous response style and the tendency to regard aggressive and verbal jokes as less funny), remain unchanged as the child grows older. Participants were 131 Estonian children aged 7–10 (M = 8,40, SD = 0,93), of whom 100 made up the control and 31 the test group. A previously developed test (Suits, 2004) for evaluating preschool children’s humor comprehension was used. Results show that children with epilepsy assessed jokes as funnier and used different explanations than healthy children (especially in verbal humor), indicating a possibility that children with epilepsy reached the same developmental stage in humor perception in primary school that healthy children reached already before starting to attend school. Keywords: verbal and visual humor, epilepsy, primary-school-aged childrenhttp://tartu.ester.ee/record=b2596697~S1*es

Characterization of reward and effort mechanisms in apathy

AbstractApathy is a common but poorly understood condition with a wide societal impact observed in several brain disorders as well as, to some extent, in the normal population. Hence the need for better characterization of the underlying mechanisms. The processes by which individuals decide to attribute physical effort to obtain rewards might be particularly relevant to relate to apathy traits. Here, we designed two paradigms to assess individual differences in physical effort production and effort-based decision-making and their relation to apathy in healthy people. Apathy scores were measured using a modified version of the Lille Apathy Rating Scale, suitable for use in a non-clinical population.In the first study, apathy scores were correlated with the degree to which stake (reward on offer) and difficulty level impacts on physical effort production. Individuals with relatively high apathy traits showed an increased modulation of effort while more motivated individuals generally exerted greater force across different levels of stake. To clarify the underlying mechanisms for this behavior, we designed a second task that allows independent titration of stake and effort levels for which subjects are willing to engage in an effortful response to obtain a reward. Our results suggest that apathy traits in the normal population are related to the way reward subjectively affects the estimation of effort costs, and more particularly manifest as decreased willingness to exert effort when rewards are small, or below threshold. The tasks we introduce here may provide useful tools to further investigate apathy in clinical populations

Dissociation of reward and effort sensitivity in methcathinone-induced Parkinsonism

Methcathinone-induced Parkinsonism is a recently described extrapyramidal syndrome characterized by globus pallidus and substantia nigra lesions, which provides a unique model of basal ganglia dysfunction. We assessed motivated behaviour in this condition using a novel cost-benefit decision-making task, in which participants decided whether it was worth investing effort for reward. Patients showed a dissociation between reward and effort sensitivity, such that pallidonigral complex dysfunction caused them to become less sensitive to rewards, while normal sensitivity to effort costs was maintained

Dopamine enhances willingness to exert effort for reward in Parkinson's disease

Parkinson's disease (PD) is traditionally conceptualised as a disorder of movement, but recent data suggest that motivational deficits may be more pervasive than previously thought. Here, we ask whether subclinical deficits in incentivised decision-making are present in PD and, if so, whether dopaminergic therapy ameliorates such deficits. We devised a novel paradigm in which participants decided whether they were willing to squeeze a hand-held dynamometer at varying levels of force for different magnitudes of reward. For each participant, we estimated the effort level at which the probability of accepting a reward was 50% - the effort 'indifference point'. Patients with PD (N=26) were tested ON and OFF their usual dopaminergic medication, and their performance compared to those of age-matched controls (N=26). No participant was clinically apathetic as defined by the Lille Apathy Rating Scale (LARS). Our data show that, regardless of medication status, patients with PD chose to engage less effort than controls for the lowest reward. Overall, however, dopamine had a motivating effect on participants' choice behaviour - patients with PD chose to invest more effort for a given reward when they were in the ON relative to OFF dopamine state. Importantly, this effect could not be attributed to motor facilitation. We conclude that deficits in incentivised decision-making are present in PD even in the absence of a clinical syndrome of apathy when rewards are low, but that dopamine acts to eliminate motivational deficits by promoting the allocation of effort.7 page(s