5 Signs Your Mental Acuity Is Low and How to Improve It

In an age of constant multitasking, long hours, and information overload, maintaining sharp mental acuity isn't just a luxury - it's a necessity. Whether you're an executive making high-stakes decisions, a student preparing for exams, or simply someone who wants to stay mentally agile as you age, cognitive clarity and focus are crucial. And now, a growing body of research suggests that photobiomodulation (PBM) - a non-invasive, light-based therapy - may help enhance brain performance at the cellular level.

What Is Mental Acuity?

Mental acuity refers to the sharpness of the mind in areas such as focus, memory, processing speed, and decision-making. This is often categorized under the broader label of ‘cognitive health’. It’s the clarity that helps you recall names, follow complex ideas, and think quickly on your feet. While many factors affect mental acuity - sleep, stress, nutrition, and age - new tools are emerging to support brain function more directly.

5 Signs of Low Mental Acuity

Poor mental acuity can look different on everyone, but common characteristics include:

• Difficulties concentrating - Many people with reduced mental acuity find it challenging to sustain attention on tasks that normally would not be difficult. This can show up as trouble focusing during conversations, difficulty following through with multi-step instructions, or being easily distracted by irrelevant details.
• Feeling like you are thinking slower than usual - A hallmark of poor cognitive sharpness is a sense of slowed processing speed. Tasks such as making decisions, solving problems, or even responding in conversations may take longer than before.
• Having a hard time recalling a particular word - Someone knows what they want to say but can’t retrieve the exact word, leading to pauses or using substitute words instead. This “tip-of-the-tongue” phenomenon is common for people with low mental acuity.
• Impaired memory - This can show up as forgetting appointments, misplacing items, or needing repeated reminders. Impaired memory may affect both short-term recall and long-term memory.
• Becoming quickly fatigued from typical tasks - Cognitive fatigue often sets in when the brain is working harder than usual just to complete routine activities. Tasks like reading, writing emails, or attending meetings can feel draining, leaving the person exhausted after short periods of effort.

Luckily, more and more neurotechnologies are emerging to address this issue, and transcranial photobiomodulation (tPBM) is one of them.

💡How does tPBM Promote Mental Acuity?

Transcranial photobiomodulation (tPBM) uses red or near-infrared (NIR) light to stimulate cellular activity in the brain. By delivering specific wavelengths of light (often in the range of 600–1100 nm), PBM penetrates tissue and activates the mitochondria - the cell’s powerhouses - to produce more adenosine triphosphate (ATP) (Hamblin, 2017). More ATP means more energy for neurons to fire efficiently, communicate better, and repair themselves when needed. On a cellular level, tPBM can help enhance mental acuity by…

• Promoting neuroplasticity - Supporting neuroplasticity is essential for learning and adapting - processes that become significantly harder when cognitive health is compromised (Wade et al., 2023).
• Enhancing ATP production - ATP is the cell’s primary energy source, so optimal cellular function depends on efficient ATP production (Hamblin, 2017).
• Increasing Brain Derived Neurotrophic Factors (BDNF) - BDNF plays a crucial role in the growth, maintenance, and activity of neurons in the brain, which is essential for promoting mental acuity (Kazemi et al., 2025)

The Science Behind PBM for Cognitive Enhancement

Research on transcranial PBM - the application of NIR light to the head - has shown promising results in enhancing brain function:

• Improved working memory: Working memory is the ability to hold and manage information in your mind while carrying out tasks. Studies have shown that PBM not only improves working memory through various cognitive testing, but that these results can last up to three weeks since the last tPBM session (Qu et al., 2022).
• Enhanced attention and decision-making: A study using a mouse model found that exposure to infrared light not only enhanced working memory but also led to more deliberate decision-making behavior, resulting in overall improvements in cognitive function (Michalikova et al., 2008). These effects weren’t limited to animals. In a separate study, Barrett and Gonzalez-Lima (2013) demonstrated that humans treated with a 1064 nm laser showed improved performance on tasks involving sustained attention and reaction time—both of which are key components of sound decision-making.
• Optimized Sleep: Poor sleep often results in poor executive functioning, which contributes to overall mental acuity. A recent 2025 study found that just one 10-minute session of PBM led to significant reductions in sleepiness, anxiety, stress, and depression scores (Zhang et al., 2025). Participants also demonstrated better regulation of alpha and gamma brain waves, which may help explain the observed improvements in mood and cognitive function.

‍

Light that Fuels Clarity and Focus

Whether you’re trying to hit your peak professionally or reduce age-related cognitive decline, PBM may offer support. Unlike stimulants or quick fixes, PBM works with the body’s own cellular machinery to promote long-term brain health. It’s safe, non-invasive, and supported by a growing base of peer-reviewed evidence.

‍

Learn More:

‍

References:

Barrett, D. W., & González‑Lima, F. (2013). Transcranial infrared laser stimulation produces beneficial cognitive and emotional effects in humans. Journal of Neuropsychology, Neuropsychobiology, and Behavior, 23(4), 301–307. Retrieved from https://www.gwern.net/doc/nootropic/2013-barrett.pdf

Hamblin, M. R. (2018). Mechanisms and mitochondrial redox signaling in photobiomodulation. Photochemistry and Photobiology, 94(2), 199–212. https://doi.org/10.1111/php.12864

Kazemi, M., Motamed Nezhad, A., Hajisoltan, R., Ramezani, F., Taherkhani, S., Moayer, F., Moayer, F., Janzadeh, A., Dadseresht, A., Ahadi, R., Mojarad, N., Eftekharzadeh, M., & Gorjipour, F. (2025, May 30). Photobiomodulation therapy: Location‑dependent effects on memory and recovery in male adult rats with spinal cord injury. Journal of Neuropathology & Experimental Neurology. https://doi.org/10.1093/jnen/nlaf051

Michalikova, S., Ennaceur, A., van Rensburg, R., & Chazot, P. L. (2008). Emotional responses and memory performance of middle-aged CD-1 mice in a 3D maze: Effects of low infrared light. Neurobiology of Learning and Memory, 89(4), 480–488. https://doi.org/10.1016/j.nlm.2007.07.014

Qu, X., Li, L., Zhou, X., Dong, Q., Liu, H., Liu, H., Yang, Q., Han, Y., & Niu, H. (2022). Repeated transcranial photobiomodulation improves working memory of healthy older adults: Behavioral outcomes of poststimulation including a three‑week follow‑up. Neurophotonics, 9(3), 035005. https://doi.org/10.1117/1.NPh.9.3.035005

Wade, Z. S., Barrett, D. W., Davis, R. E., Nguyen, A., Venkat, S., & Gonzalez‑Lima, F. (2023). Histochemical mapping of the duration of action of photobiomodulation on cytochrome c oxidase in the rat brain. Frontiers in Neuroscience, 17, 1243527. https://doi.org/10.3389/fnins.2023.1243527

Zhang, X., Miao, X., Jiang, H., Ren, Y., Huo, L., Liu, M., & Chen, H. (2025). Advanced intervention effects of pulsed and steady transcranial photobiomodulation on sleep, mood, and EEG signal regulation. Journal of Biophotonics, 18(1), e70004. https://doi.org/10.1002/jbio.70004

‍