NCT02363504

The Locus Coeruleus and Memory

Focus on the Locus Coeruleus Network With 7 T MRI: Link to Memory (Dys)Function

• Status: Unknown
• Phase: —
• Study type: Observational
• Enrollment: 70 (estimated)
• Sponsor: Maastricht University Medical Center · Academic / Other
• Sex: All
• Age: 60 Years – 85 Years
• Healthy volunteers: Accepted

Summary

The cause of Alzheimer's disease, the most common form of dementia, remains unknown. Neuropathological studies suggest that a small area in the brainstem, the locus coeruleus, might be the site of the onset of the disease. This area is the sole source of noradrenalin to the brain, a neurotransmitter involved in arousal, but also cognitive functions. Animal and pharmacological studies have hinted towards an important role of this area in memory functioning. However, these studies were hampered by the limited spatial resolution, making it hard to clearly localize the locus coeruleus in the brain. New developments in brain imaging allow now to visualize the brain with stunning precision. Furthermore, a non-invasive new stimulation method, transcutaneous vagus nerve stimulation, is believed to excite the locus coeruleus and thereby influencing neuronal networks and memory functioning. There are three aims in this project: 1. To investigate how the functional interaction between the locus coeruleus and other brain areas, in particular the medial temporal lobe areas, during memory processes (encoding, consolidation and retrieval) change with development of Alzheimer's disease. 2. To investigate associations between noradrenaline, memory performance and brain functioning. The investigators aim to investigate how acute noradrenalin levels change during the different memory processes and whether or not this is beneficial for performance. Furthermore, the investigators will investigate whether this interaction between noradrenalin, memory performance and brain functioning is different healthy older individuals (n =35) or patients with prodromal Alzheimer's disease (n =35). 3. To investigate the underlying neural network changes during transcutaneous vagus nerve stimulation. The investigators will focus on differences in functional connectivity between the locus coeruleus and the medial temporal lobe areas in healthy older individuals and prodromal Alzheimer's disease patients. An experimental condition will be compared with a sham condition in a pseudo-randomized cross-over design.

Conditions

• Alzheimer's Disease

Interventions

Type	Name	Description
OTHER	7 Tesla MRI with memory task and non-invasive neurostimulation	This is not an intervention, we investigate the neural mechanisms

Timeline

• Start date: 2017-02-01
• Primary completion: 2020-12-01
• Completion: 2020-12-01
• First posted: 2015-02-16
• Last updated: 2020-02-28

Locations

1 site across 1 country: Netherlands