Animal models play a central role in investigation of behavioural and cognitive processes and the underlying biological mechanisms, understanding diseases and development of translational therapies. Although there is no perfect animal model that replicates the outcomes of cognitive decline in humans, several research paradigms could inspire development of new instruments to study everyday performance and changes thereof associated with cognitive decline in human.
Spatial navigation tasks provide a notable example of such translation. Such paradigms are widely used by neuroscientists in animal behavioural procedures as powerful tools of studying memory, learning, spatial navigation and behavioural responses to various interventions such as drugs and brain lesions. Spatial navigation tasks tend to fall into one of two categories: goal-directed way finding and free exploration. Examples of the former are the traditional behavioural procedures such as the Morris water maze task, or the radial arm maze, where exploration is motivated by the presence a reward; thus it is useful to assess the animals’ learning and memory capacity. In contrast, free exploration paradigms such as the Open-Field test provide quantitative as well as qualitative measures of general locomotion.
Example of a free exploration paradigm with automated activity tracking tracking (source: Hong C.J., http://psylab.idv.tw/Animal%20models%20of%20depression-detail.htm, Oct 15, 2006)
While traditionally the analysis of animal behaviour relied on the researchers’ observation and notation only, in the recent years, we have seen a development in technology specifically designed for the purpose of activity tracking. Modern tracking technology enables activity recording and frame-by-frame event analysis and reporting behavioural parameters.
The Spatial Mapping study at the RNG aims to built upon what we know about animal models of free exploration and automated means of long-term data acquisition for quantitative and qualitative analysis. While GPS-based tracking of activity has been implemented in studies of people of people with moderate and advanced dementia, this tends to reflect severe symptoms of cognitive decline such as outdoor wandering, which does not manifest in the early stages. Instead, this projects aims to use unobtrusive indoor tracking approach to track and map the activity of at-risk elderly in their own homes, akin to the data generated on spatial navigation tasks in animals. Hence, spatial mapping data could potentially provide spatio-temporal parameters that mark early cognitive decline.
Where are we now?
We have teamed up with a US-based global navigation company Navizon™ to generate a indoor triangular positioning (ITS) solution based on WiFi transmission for accurate real-time indoor localisation of a WiFi wristband tag which is worn by our study volunteers. Below are the images from two pilot trials, where the colourful trail represents a activity within a 24 hour window within the house.
Ultimately, this study aims to:
- Evaluate the feasibility of a WiFi-based tracking system as a potential diagnostic tool, with regards to spatial and temporal accuracy and participant comfort;
- Determine differences in at-home spatiotemporal activity patterns differences between elderly of various cognitive states;
- Validate the reliability, sensitivity and feasibility of short-term home-based spatial tracking as an ecologically valid marker of early cognitive and functional impairment, by statistical comparison with traditional validated assessment tools.