Periodic Reporting for period 1 - NEURO-AGE (Addressing Neural Declines to Promote Healthy Ageing)
Reporting period: 2017-09-01 to 2019-08-31
The ability to quickly select the correct action to perform is essential to everyday life; for example, when driving a car, if we see a red light, it is essential that we can quickly choose the correct response of applying the brakes. This depends firstly on our ability to learn that we must respond to a red light by stopping, and secondly on our ability to make what we have learned automatic by practicing it. The ability to select responses therefore depends on an important combination of both our ability to think, and to move. Both of these abilities are affected by ageing, making it is important for us to improve our understanding of how we learn to select responses, understand how this is affected by ageing, and identify ways in which we could improve our ability to select appropriate responses.
The overall objectives of this project are to measure the problems that older adults have when attempting to select appropriate responses, to develop new approaches to improve our ability to select responses, to identify the regions of the brain that are involved in action selection tasks, and to learn whether the ability to select responses can be predicted by combining data from performing action selection tasks with data from scans of the brain.
Based on the findings of the project, we are able to conclude that older adults do not slow down to favour accuracy - the slowing of their actions is part of a general age-related reduction in performance, that we can enhance the rate of learning using novel training paradigms developed during this project, and that a cerebellar-cortico network underlies behavioural response selection.
We then examined a more complex response selection task (pressing buttons in response to different symbols), asking participants to try to stop themselves from performing 'bad habits' that they had made automatic through practice. We predicted that this would be simple to overcome a bad habit when people had plenty of time, but that applying time pressure would make it more difficult. After training participants for several days, we found that they could easily overcome these bad habits when given plenty of time - at first appearance, it would seem that they did not have a bad habit to overcome. However, when we applied time pressure, the participants found it much more difficult to hide their bad habits. We are in the final stages of examining how this effect changes with age.
We then developed a new approach to speed up the process of learning to select appropriate responses. We compared two groups of participants; one group who sometimes had to select the same response twice in a row, and another group who rarely had to select the same response twice in a row. We found that participants who rarely had to select the same response twice in a row learned the task faster; we believe this is because the constant switching of the required response made the task more challenging.
The final part of the project is examining how the structure of the brain affects our ability to select and perform appropriate responses. Using data from over 300 participants, we separate the brain into 96 different areas, and are developing computer code that can learn how the volume of these different areas relates to the ability to select responses. Using advanced (machine-learning) computing techniques, we are currently developing tools that attempt to predict how well a person is able to select appropriate movements based on the volume of different areas of their brain.
To date work from the project and related research has so far led to three publications in scientific journals, and five presentations at international research meetings.