The 4 Things Most Likely Affecting Your Brain Function

Where did I put my keys? What was that woman’s name again? Why am I so tired lately? Did I just read the same paragraph three times?

If you find yourself asking these questions a lot lately, you’re probably also asking what’s going on with your brain. Before you Google “Alzheimers symptoms,” consider that a lot of (seemingly) unrelated factors can really mess with your brain performance, from a poor diet to that upcoming work presentation you’ve been dreading.

In fact, some of the biggest factors influencing our cognitive performance and our feelings (yes, they can affect each other) are challenges the majority of us encounter throughout their lives. In this post, we’ll outline how “the big four” are impairing your brain function -- and how to improve brain performance despite the challenges they pose.


Of the four core brain functions, stress falls under “feelings,” driven by another core brain function: emotions. According to the American Institute of Stress, 73% of people have experienced high enough bouts of negative stress that it has affected their mental health, and 48% have been under enough stress that it disturbed their sleep. Money, relationships, and work are some of the more frequently cited causes for high stress levels. While everyone experiences stressful times, there is an actual tipping point that will have much bigger effects on brain function. (To learn more about stress and how it derails our cognitive abilities, download our ebook.)

What does stress do to the brain?

How does stress affect the brain? You’d be surprised -- neuroscience research has taught us that stress depletes brain cells, shrinks brain size, and disrupts synapse regulation -- which can drastically impede our ability to focus and remember things. And emotionally, it can take away the desire to socialize with others. In children, “toxic stress” can even change the architecture of the brain as it develops.

How to combat stress’ impact on the brain

A long-term solution to better handling stress is to boost our resilience. Resilience is what allows us to adapt to, and overcome, adversity. It’s not something you’re born with but something you gain and develop over time -- by reinforcing the five factors that help us overcome adversity: positive self-belief (confidence that you can learn from adversity); flexible thinking (the ability to pivot your thinking to overcome a problem); stress recovery (utilizing strategies that help you deal with stress, life practicing self-care); a positive attitude (practicing optimism rather than dwelling on the negative); and having a social support network (family, friends, support groups, etc.). 

Leveraging these five factors through our thoughts, behaviors, and action takes time to master, and should be paired with in-the-moment handling of stress (via breathing tricks and meditation exercises). 

Ready to boost your resilience over time, and tackle stress in the moment? Download the Total Brain app to do both, and read our guide on improving resilience.


Stimulants like nicotine and caffeine -- as well as depressants like alcohol and some prescription drugs -- have different effects on the brain that can be amplified over long periods of time. We’re not talking about that morning cup of coffee, but rather abuse (excessive use of a substance) and addiction (physical and psychological reliance on substance). If you’ve noticed a change in brain performance and you’re struggling with substances, it’s likely there’s a connection between the two -- and you’re not alone: almost 21 million Americans have at least one addiction.

How can different substances affect the brain?

Stimulant use in the short term can cause anxiety and difficulty sleeping, but in the long term can yield psychiatric problems like psychosis and suicidal feelings. Regular and extended use of stimulants like cocaine can actually change how the brain makes decisions (based on a reward and punishment system). Other effects include reduced ability for sustained attention and lowered motivation. Long-term use of depressant substances affects the central nervous system in various ways, from a lack of inhibition to difficulty concentrating. Alcohol abuse over time is the most common cause of Korsakoff Syndrome, which can bring about amnesia and confusion. 

For those trying to break the pattern of substance abuse and addiction, you may notice the temporary effects of the sobriety process can have different brain functions, from mood swings to the struggle to manage impulses. Even those of us who enjoy a morning coffee will feel the mental effects when we skip it -- the absence of caffeine causes the brain to fill those receptors with adenosine, which can make us feel sleepier and mentally slower. (A small study showed that caffeine withdrawal temporarily reduced grey matter in the brain, particularly in the area that consolidates memories.)

Addressing substances and brain function

When you consume a substance -- particularly one that is addictive -- your brain is “rewarded” with a dopamine hit (which creates that short-term satisfaction). If you’re trying to abstain from a substance, the brain goes into flight-or-fight mode because (after all, it is a safety-first organ). The good news is that some mental exercises can help train the brain to be more effective at moderating cravings for that dopamine hit. 

Poor self-control and lower levels of resilience are associated with relapse, but digital tools can help address addiction challenges. Game based apps like Total Brain have shown to improve self-control, making it easier to overcome cravings (when paired with clinical treatment). The games develop several brain functions associated with superseding the ill effects brought on by addiction recovery: brain exercises for stress mastery are key because they teach your brain to move into a flexible state (and away from fight-or-flight). Meditations and exercises that help users to be present can raise awareness of  subconscious cravings and reveal which their triggers test our impulse control. Digital brain exercises work best when they are personalized, something Total Brain users enjoy thanks to our 15-minute assessment. 

Among Total Brain users battling substance abuse in a clinical setting, those who engaged in immersive brain training -- like self-affirmation exercises -- for three hours a month showed significant improvement in self-control levels.


People can experience sleep problems whether they’re getting to bed early or spending too much time on their phones late at night. That’s because sleep is also about quality, not quantity, and it’s not always easy to tell if our R.E.M. is constantly interrupted. The CDC says one in three adults don’t get enough sleep (which the organization describes at seven hours per night). Even if you’re going to bed on time, you may be one of the more than 50 million Americans who have a sleep disorder. The number of adults taking melatonin today has doubled since 2007, and while it’s a naturally occurring hormone, it can have some effects on brain function despite a better night’s sleep, including temporary feelings of depression, mild anxiety, and reduced alertness.

How sleep affects the brain

Sleep and the brain have a close knit relationship. A lack of sleep has effects on brain function that you’d expect (it’s hard to remember things, or you’re slower to problem solve) and may not expect (like the ability to process emotions.

10% of the population experiences sleep apnea at some point, with those who are overweight or over fifty-years-old at higher risk. This treatable condition periodically blocks the windpipe while someone is sleeping, which deprives the brain of oxygen (and...may deprive your partner of some much needed sleep). The result is daytime fatigue and deficits in brain capacity, such as reduced function in memory, focus, and decision-making processes. (We break down the fascinating neuroscience behind memory in this brief video.

Do you have difficulty falling and staying asleep? You may be suffering from the more common sleep insomnia, characterized by difficulty falling and staying asleep. Anxiety, depression, and some chronic illness can cause sleep insomnia.

How to deal with sleep deprivation’s effects on the brain

There are several steps sleep apnea sufferers can take, including weight loss and the assistance of a CPAP machine, but there’s also brain exercises to battle the impact poor sleep has on memory functions. Total Brain’s brain exercises for memory and fatigue like Think Memory, Think Focus, and Power Nap can all offer relief. Total Brain includes questions in the onboarding assessment that screens for sleep apnea with 80% accuracy. App users who screened positive for being at-risk for sleep apnea did show deficits in cognition and resilience, as well as anxiety and depression. See if you’re at risk.

Thanks to modern scientists, we better understand how things like brain games can train our brains to better memorize things. Techniques like chunking (grouping info into threes); practicing order (remembering sequences); and making associations (connecting new information to known information) can all be strengthened with memory exercises like Total Brain’s Memory Maze and Word Lists. Even one night of bad sleep (apnea or not) can cause reduced brain function the next day -- so when you’re not training on Total Brain, follow our four science-backed ways to restore mental energy.

Mental Health Risk Factors

It’s common knowledge that mental risk factors like ADHD and focus can be opposing forces, but it's not as commonly known that depression, anxiety, and PTSD sometimes cause the same problems with brain performance. More than a quarter of Americans over the age of 18 suffer from a mental disorder in any given year. According to the National Institute of Mental Health, the most common mental illnesses are bipolar disorder (of which there are several types), Obsessive-Compulsive Disorder (OCD), major depression, eating disorders, and Post-Traumatic Stress Disorder (PTSD). But many of these conditions can go undiagnosed -- and untreated. Those at risk for mental illness don’t always know the signs, or feel that help is not accessible, leading to brain function problems that remain unaddressed.

Understanding brain performance and psychology

Mental health conditions affect brain function in different ways. People with Major Depression may be surprised to find out all the ways depression affects the brain, beyond sad feelings. “Depression brain fog” can impair memory formation, and lead to slowed reaction times and poor concentration. Attention Deficit Hyperactivity Disorder (ADHD) has been associated with impaired cognitive development, affecting impulse control and working memory. Generalized Anxiety Disorder (GAD) puts the brain in a prolonged state of fight-or-flight, which can greatly influence how our brain makes decisions. Brain imaging of patients with OCD shows that the condition locks the brain in ERN -- error-related negativity -- which can really mess with their emotional responses.

How to improve brain function in the face of mental health challenges

Exercising different brain functions through brain training games -- as well as exercises around breathing and meditation -- can help manage some of the toll that mental health challenges take on our performance. 

PTSD, depression, and anxiety create an influx of negative emotions, which can be compounded by pervasive negative thinking, a result of strong conscious negativity bias. What is negativity bias? Conscious negativity bias the degree to which anything is perceived as potentially negative or threatening. A strong negativity bias can derail your brain performance, affecting feelings and behavior. There are connections between negativity bias and anxiety, so training your brain to overcome conscious and nonconscious negativity will make a difference. Total Brain’s adjunctive digital exercises that can help with this include the CBT-based Thought Tamer, gratitude mindfulness meditations, Emotion Booster, and stress reduction exercises. 

In the era of multitasking and smartphone distractions, concentrating can be a tall order. Engaging in focus games for ADHD is a start (while not formulated exclusively for ADHD, they are still effective in improving the ability to ignore distraction until a task is completed). Learn more about how to improve focus using a five-step pathway, and watch our short video on the three types of focus to better understand how we use neuroscience to improve brain function.

In addition to any needed medication and brain exercises, practice these 5 things to improve your ability to focus at work. You can also up your focus factor with breathing exercises, which require practitioners to constantly return to the present and focus on the moment. 

You don’t have to wrestle with insurance to get a work up on your brain -- start by using easily accessible technology to find out what might be impairing your brain function, and assess your brain’s strengths and areas where you can improve. 

Take Total Brain’s quick, interactive assessment to get a personalized brain training plan that can help you improve memory, focus, mood, energy, and overall well being. Total Brain’s brain exercises include a variety of brain games that have shown to improve brain function for those who train regularly -- and regular assessments will show all the progress you’re making. And, users have access to an expansive library of articles, videos, and guided meditations to learn more about how internal and external factors that our brains love (and...don’t love).

Interested in screening for these four risk factors? See how the Total Brain app works, from assessment to training. Don’t waste time wading through apps that aren’t based in neuroscience -- download Total Brain today from the App Store or Google Play.

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