There are early signs, and being genetically predisposed for Alzheimer’s affects spatial navigation in a way that might be more easily tested for intervention against the disease.
- Researchers studied 75 young adults, half of whom carried the APOE4 gene
- The APOE4 gene is said to occur in 1 in 6 adults, and increases the chance of Alzheimer’s 3 times over
- The participants were asked to navigate a maze
- The APOE4 gene carriers showed a different approach, and different activity in the brain
Alzheimer’s is an incurable and untreatable condition that presents with severe loss of memory and disorientation. It cripples the lives of the patients and their family, and it’s difficult to tell when it will begin. The problem often roots in the fact that drugs and medication only come into play by the time the brain has been irreversibly damaged.
Early on detection could be the ultimate key to help future patients with the crippling condition.
Researchers studied a number of 75 young adults, half of whom carried a variant of the Apolipoprotein E (APOE). The APOE4 gene is said to be found in 1 in 6 people, which increases the chance of developing Alzheimer’s three fold. By studying its effects, the scientists hoped they could find clues to unlock early on detection.
They observed how the participants handled spatial navigation. All the young adults were placed in a virtual maze. It tested their abilities to both navigate the labyrinth and their memory by asking them to take certain objects, and place them in designated places.
In order to keep track of their brain activity, the researchers kept an eye on the entorhinal cortex, which contains grid cells. They are responsible for spatial navigation, and earlier studies have found that they can be tracked using magnetic resonance imaging (MRI). The researchers analyzed the grid patterns while the participants navigated through the maze.
According to lead author of the study, Dr. Nikolai Axmacher, APOE4 carriers applied a different strategy than those with lower risk of developing Alzheimer’s. The ‘risk carriers’ mostly navigated the borders of the maze, while the others were not afraid to work more in the center. The grid cells of those with the gene variant showed less activity.
As observed by Dr. Axmacher and his team, while risk carriers were less active in their entorhinal cortex, they compensated through the hippocampus, an adjacent area in the brain. It appeared that those with high predisposed genetic risk of developing Alzheimer’s showed signs early on.
It’s in the hopes of the researchers that this will provide with a better understanding of how the crippling condition affects the brain at a younger age. And more importantly, if that particular area of the brain could be enhanced and improved through medication.
Image source: rodmartin.org