A team of scientists from Nanyang Technological University, Singapore (NTU Singapore) has demonstrated that communication among memory-coding neurons(神经元)—nerve cells in the brain responsible for maintaining working memory—is disrupted with ageing and that this can begin in middle age.
Findings from the study provide new insights into the ageing process of the human mind. and pave the way for therapies(治疗方法) to maintain the mental well-being of an ageing individual.
Scientists have long studied the impact of ageing on the brain's executive functions, such as poorer self-control and working memory. While it is well established that memory can worsen as people age, it has not been clear what changes occur at the individual brain neuron level to cause this—until now.
In lab experiments, the NTU scientists investigated how neurons in mice of three different age groups—young, middle age and old age—responded to tasks that required memory.
The researchers showed that compared to young mice, middle—aged and old mice required more training sessions to learn new tasks, indicating some decline in memory and learning abilities from middle age. But beyond that, they also found changes in the nerve cells of older mice.
Using advanced optical techniques that allow researchers to observe multiple individual neurons and control their activity, the NTU team discovered that neurons in one part of the brain, the prefrontal cortex, showed strong memory coding ability in young mice. However this ability to hold memory diminishes in middle—aged and old mice due to weakening connections among the neurons, which causes the mice to take longer to recall and perform tasks.
Dr Jun Nishiyama, Assistant Professor in the Neuroscience and Behavioural Disorders programme at Duke-NUS Medical School said. "This research emphasises the importance of early, strategic interventions (干预) to cope with cognitive decline, providing a vital framework for future ageing research and brain health maintenance.
