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Current clinical trials are investigating gamma frequency sensory stimulation as a potential therapeutic strategy for Alzheimer's disease (AD); yet, we lack a comprehensive picture of the effects of this stimulation on multiple aspects of brain function. We previously showed that exposing mice to visual flickering stimulation increased mitogen activated protein kinase and nuclear factor kappa-light-chain-enhancer of activated B cells signaling in the visual cortex (VC) in a manner dependent on the duration and frequency of stimulation. Because these pathways control multiple neuronal and glial functions, here we aimed to define the transcriptional effects of different frequencies and durations of audiovisual flicker (AV flicker) stimulation on multiple brain functions. Within the VC, we found that all stimulation frequencies caused fast activation of a module of immune genes within 0.5 h and slower suppression of synaptic genes after 4 h. In the hippocampus, we found that a 20 Hz AV flicker activated a module of genes associated with mitochondrial function, metabolism, and synaptic translation, while 10 Hz rapidly suppressed a module of genes linked to neurotransmitter activity. Collectively, our data indicate that the frequency and duration of AV flicker stimulation control immune, neuronal, and metabolic genes in multiple regions of the brain affected by AD.
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Acute immune system activation exerts time-dependent effects on inhibitory control: Results of both a randomized controlled experiment of influenza vaccination and a systematic review and meta-analysis – ISPNE 2024 Dirk Hellhammer Award
Although coming down with an illness or receiving a vaccine are both common experiences, the influence of such acute immune system activations on cognitive processes, such as inhibitory control, has received relatively little attention. We addressed that issue by assessing the effects of acute immune system activation on inhibitory control in a randomized controlled experiment, and by conducting a meta-analysis of similar studies in humans. In our experiment, we found—somewhat surprisingly—that influenza vaccination improved performance on both of our inhibitory control outcomes (i.e., stop-signal reaction times and flanker interference effects). At the meta-analytic level, we found that at a short delay (1.5–4 hours post-injection) between immune activation and inhibitory control assessment, such activation impaired multiple forms of inhibitory control, whereas after a longer delay (e.g., > 18 hours post-injection), such activation improved inhibitory control—consistent with our experiment. Moreover, proinflammatory cytokine activity predicted poorer interference control but better response inhibition, even with a long delay between injection and testing. Together, these results highlight nuanced, time-dependent, and—perhaps—multiple-mechanism-driven effects of acute immune system activity on inhibitory control.
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- Award ID(s):
- 2338789
- PAR ID:
- 10589487
- Publisher / Repository:
- Elsevier/Psychoneuroendocrinology
- Date Published:
- Journal Name:
- Psychoneuroendocrinology
- Volume:
- 171
- Issue:
- C
- ISSN:
- 0306-4530
- Page Range / eLocation ID:
- 107186
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.psyneuen.2024.107186
