Cell death causes loss of human orientation

Cell death in the brain system may be the reason elderly people are inclined to lose orientation, researchers say.

A new study compared brain activity patterns to a group of young and old adults after they completed a number of orientation tasks to shed light on why the feeling of orientation fades over age.

They found that an area of the brain that is central to orientation becomes increasingly unstable with age among healthy adults and similarly among people with degenerative diseases such as Alzheimer's.

The findings can be used not only to slow down the navigational capacity but also to diagnose and treat diseases that cause a decline in cognitive abilities and give the elderly less independence.

Space navigation and navigation are considered to be some of the most complex capabilities of the human mind, since they require processing a flood of information, including sensitive incentives and muscle balance signals.

These skills have been found to deteriorate with age, which can compromise a person's independence later in life.

When you move around an unknown environment, it's perfectly normal to lose. However, this tends to happen more often in older people. So far, we know very little about the neuroal mechanisms of these navigational problems”, said the chief author of the study, Mattias Stinger.

The study was drafted about a hypothesis that the deterioration was linked to network cells, which are important for the processing of orientation.

Researchers conducted a series of experiments using virtual reality and drawing brain activity through functional brain image ( FMRI). They divided 41 healthy adults into two groups: a group of reï with 20 participants between the ages of 19 and 30 and a group of older ones with participants aged 63 and 81.

For the first experiment participants had to be guided through a virtually realised virtual environment, while their brain activity was monitored.

In the second experiment, participants moved along the predetermined trails into a real space and environment of virtual reality with random stoppages where they had to assess their distance and orientation regarding the starting point without being able to see or identify its location.

“All the things considered, the new participants did best in navigation, which is in line with previous studies. However, we have found a link between reduced navigation performance and deficits in cell network activity, “said Thomas Wolbers, research supervisor and a senior DZNE scientist.

The results showed that the extenuating “patterns in network cells were less stable in the oldest group, which explains why older people are more often faced with space orientation.

Besides their role in navigation, network cells are used for other cognitive functions.

Wolbers said the findings give knowledge of early neurophysiological changes that can be used in drawing treatments for diseases such as Alzheimer's that cause a loss of cognitive skills.

The assessment of orientation performance and the function of network cells may facilitate the early diagnosis of Alzheimer's and other neurodegenerative disorders,” he said.

The study of the German Center for Neuroderative Disease was published in the magazine Current Biology.