University Hospital of Old Age Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland.
Graduate School for Health Sciences, University of Bern, Bern, Switzerland.
Sci Rep. 2024 Oct 3;14(1):22985. doi: 10.1038/s41598-024-74029-9.
Frontal and parietal brain regions are involved in attentional control and prospective memory. It is debated, however, whether increased or decreased activity in those regions is beneficial for older adults' task performance. We therefore aimed to systematically modulate activity in those regions using high-definition transcranial direct current stimulation. We included n = 106 healthy adults (60-75 years old, 58% female) in a randomized, double-blind, and sham-controlled study. We evaluated task performance twice in the laboratory and at home and additionally assessed heart rates. Participants received cathodal, anodal, or sham stimulation of the left or right inferior frontal lobe, or the right superior parietal lobe (1 mA for 20 min). Performance improved at visit two in laboratory tasks but declined in at-home tasks. Stimulation did not modulate performance change in laboratory tasks but prevented decline in at home-tasks. Heart rates increased at visit two but only when right inferior frontal lobe activity was inhibited. Repeating a task seems more beneficial than stimulation for laboratory tasks. This might be different for at-home tasks. Inhibiting right frontal brain function increases heart rates, possibly due to a modulation of the frontal-vagal brain-heart axis.
额顶叶脑区参与注意力控制和前瞻性记忆。然而，这些区域的活动增加或减少是否对老年人的任务表现有益仍存在争议。因此，我们旨在使用高清晰度经颅直流电刺激系统地调节这些区域的活动。我们在一项随机、双盲、假刺激对照研究中纳入了 106 名健康成年人（60-75 岁，58%为女性）。我们在实验室和家中两次评估了任务表现，此外还评估了心率。参与者接受了左侧或右侧下额叶或右侧顶叶上区的阴极、阳极或假刺激（1 mA 持续 20 分钟）。在实验室任务中，第二次就诊时表现有所提高，但在家中任务中表现下降。刺激并未调节实验室任务中的表现变化，但可防止在家中任务中下降。心率在第二次就诊时升高，但仅当右侧下额叶活动受到抑制时才会升高。重复任务似乎对实验室任务更有益，而对家庭任务则不然。抑制右额叶脑功能会增加心率，这可能是由于对额-迷走神经脑-心轴的调节。
