Biology subjects

Gausterer, C.

Publications and source records attributed to Gausterer, C..

3 recordsLinked to original sources

bioRxiv2026

No effects of APOE ε4 on spatial navigation and broader cognition in young adults genetically at risk for Alzheimer's disease

Alzheimers disease (AD) causes progressive memory loss and disorientation. It is preceded by a prolonged preclinical phase marked by pathological changes in medial temporal lobe regions involved in spatial navigation. Spatial navigation tasks have been proposed for early AD detection, and altered navigation performance was reported in older carriers of the apolipoprotein E (APOE) {varepsilon}4 allele, the major genetic risk factor for sporadic AD. However, whether spatial navigation or other cognitive abilities are affected in younger {varepsilon}4 carriers remains unclear. Here, we genotyped 1000 healthy young adults (18-35 years) who completed the app-based navigation game "Sea Hero Quest" and several tasks assessing working memory, processing speed, executive functioning, and face recognition. {varepsilon}4 carriers ({varepsilon}3{varepsilon}4, N = 88) showed no significant differences from non-carriers ({varepsilon}3{varepsilon}3, N = 327) in spatial navigation or other cognitive abilities, supported by equivalence testing and Bayesian analyses. Exploratory findings suggested altered spatial navigation in {varepsilon}2 carriers ({varepsilon}2{varepsilon}2/{varepsilon}2{varepsilon}3/{varepsilon}2{varepsilon}4, Ns = 7/51/7) versus {varepsilon}3{varepsilon}3 controls, who stayed closer to environmental borders and showed better memory updating, face recognition, and processing speed. Therefore, APOE-related behavioural differences in young adults appear small at best, highlighting the need for paradigms sensitive to very subtle changes decades before potential dementia onset.

neuroscience↗

bioRxiv2022

Effects of dopamine D2 and opioid receptor antagonism on the trade-off between model-based and model-free behavior in healthy volunteers

Our daily behaviour requires a flexible arbitration between actions we do out of habit and actions that are directed towards a specific goal. Drugs that target opioid and dopamine receptors are notorious for inducing maladaptive habitual drug consumption, yet how the opioidergic and dopaminergic neurotransmitter systems contribute to the arbitration between habitual and goal-directed behaviour is poorly understood. By combining pharmacological challenges with a well-established decision-making task and a novel computational model, we show that the administration of the D2 dopamine receptor antagonist amisulpride led to an increase in goal-directed or model-based relative to habitual or model-free behaviour, whereas the non-selective opioid receptor antagonist naltrexone had no appreciable effect. These findings highlight the distinct functional contributions of dopamine and opioid receptors to goal-directed and habitual behaviour and support the notion that D2 receptor antagonists promote stabilisation of goal-relevant information.

neuroscience↗

bioRxiv2020

A causal role for estradiol in human reinforcement learning

The sex hormone estrogen is hypothesized to play a key role in human cognition via its interactions with the dopaminergic system. Work in rodents has shown that estrogens most potent form, estradiol, impacts striatal dopamine functioning predominately via increased D1-receptor signalling, while human work has suggested that high estradiol levels are associated with altered reward sensitivity. Here, we addressed two fundamental questions: 1) whether estradiol causally alters reward sensitivity in men, and 2) whether this effect of estradiol is moderated by individual variation in polymorphisms of dopaminergic genes. To test this, we performed a double-blind placebo-controlled administration study in which hundred men received either a single dose of estradiol (2 mg) or placebo. We found that estradiol administration increased reward sensitivity, which was moderated by baseline dopamine. This was observed in choice behaviour and increased learning rates. These results confirm a causal role of estradiol in reinforcement learning in men that is moderated by the striatal dopaminergic pathway.

neuroscience↗