Have you ever heard of executive function?
It’s the term used to classify our most important cognitive abilities. These abilities include working memory, your ability to say no, flexibility, planning for a goal, reasoning and solving problems.[1]
What does this mean in the real world?
It’s many things we aspire to have when our health isn’t where we want it to be. For example, executive functions can help with the following:
- taking the time to think before we act, otherwise known as not screaming at the person who cut you off;
- resisting temptation, otherwise known as not picking up the phone when ice cream calls you at night;
- being able to deal with unanticipated challenges, otherwise known as your tyre bursting on the way to work.
- Remembering essential tasks when working towards your goal, or more simply known as hearing Bill from business development make a presentation and remembering what he said and putting your spin on things when asked your opinion.
In this article, we will look at precisely what executive functions are, how they relate to the quality of your day and how to improve your executive function under your own steam.
Executive function is essential in almost everything we do.
And we talk about it more often than we think too.
How often do you wish you could be more disciplined or concentrate and focus when you need to?
In simpler terms, do you have an “automatic pilot” that just seems to take over at a time where you wished it wouldn’t?
All these things are down to different aspects of your executive function. In most cases, it’s a combination of them.
I’ve experienced this personally regarding my journey with different types of addiction. Sometimes you lose the ability to explain how things happen. I also hear about this a lot in the clinic regarding food, particularly sugar and alcohol.
Studies show that the troubles I experience and you may too fall in line with poorer executive functions. Obesity, overeating, substance abuse, and poor compliance to treatment are all associated with suboptimal executive functions.[2] [3] [4]
That’s not all. Executive functions are impaired in many mental health conditions, including the following:
- Attention deficit hyperactivity (ADHD)[5] [6]
- Conduct disorder[7]
- Depression[8]
- Obsessive Compulsive disorder (OCD)[9]
- Schizophrenia[10]
That’s quite the list.
It doesn’t end there, though. Less than optimal executive function is related to poor workplace productivity and can predict how good a partner you’ll be in a romantic relationship.
Yep, having poorer executive functions can make it harder for people to get along with you, with one study suggesting that it can also make you less dependable and more impulsive![11]
All is not lost, and that’s why I wrote this article.
What affects your executive function?
Stress is one of the first things to affect executive function.[12]
Other things that affect your executive function are sadness, loneliness, sleep deprivation, and low physical fitness. These different things can cause such a disproportionate effect on executive function that you can present as if you have an attention deficit or hyperactivity disorder when you don’t.[13]
Improving your relationship with stress will positively influence executive function.
No, this is not an invitation to “stress less.”
If you’ve read my stress article, you’ll know I don’t necessarily love telling people to do that because I think it’s obsolete.
Why?
Because we all have an intuitive understanding that prolonged bouts of stress aren’t good for us, we know that taking some responsibility can help. Still, life demands so much of us that escaping a higher level of engagement can be extremely difficult, particularly if you live in Hong Kong, Singapore, London or New York. However, there are ways to manage your stress over a surprisingly short time.
Based on this, it might be better first to exercise if you are not or see someone improving your sleep if these things aren’t in line with where you want them to be.
But what if being stressed means the executive function you rely upon to make those changes is impaired?
That’s a great question.
If this is the case, it’s time to do something simple and achievable that doesn’t require too much impulse control or concentration.
In my opinion, that can be using a capsulated or liquid herbal formula.
One of the key ways I feel herbal medicine can make a difference in the quality of your day is by reducing your reactivity to stress.
In the article I mentioned above, we see that functional MRI shows meditation as the best way to reduce your reactivity and response to stress. However, herbs such as Passionflower[14], Lavender[15], Ashwagandha[16]and nutritionals such as L-theanine[17] from green tea can all help you to stay calm when things get crazy.
So whilst these herbs don’t have great studies directly affecting executive function, their indirect effects help my patients greatly, especially in the initial stages of making change. We see results specifically with slowing down thought processes (working memory), impulse control and dealing with unexpected challenges.
Once these things start to feel more stable, the real solution to improving your executive function, quality of your day and perhaps your life can get underway.
It’s here that it might be good to differentiate between executive function and brain fog, particularly when discussing stress and decision-making.
What’s the difference between brain fog and poor executive function?
Firstly, in my interpretation, at least, brain fog is a broad term encompassing mental health symptoms that include poor executive function. For example, along with poor executive function, which may consist of being unable to say no when you want or not being able to solve an unexpected challenge, brain fog could also include language, memory, recall, focus and attention.[18]
Whilst this definition is my interpretation regarding how I see both present in the clinic, I see many high-functioning people who experience brain fog. In contrast, I see people without brain fog who have trouble making decisions about their health and executing some of the cognitive abilities we’ve touched on, such as impulse control.
It would be fair to say that one definitely affects the other. Both can benefit from the one dietary change I’ve mentioned in the title of this article.
Diets high in fruits and vegetables improve executive function.[19]
And we can see this a lot, especially in our children and teenagers.[20]
The problem is that poor executive function is associated with higher consumption of unhealthy foods[21] , which, of course, can make it harder to change.
This challenge is where the real solution lies. Small steps. For example, let’s say you’re eating within Hong Kong standards, and your current dietary intake is around 1-2 serves of fruits and vegetables a day.[22]
Why not start by adding one extra serving of vegetables to lunch and dinner?
That’s half to one cup extra to begin. Even when you are eating out, just commit to that, and immediately you’ll double your intake without thinking.
From there, each time you achieve this, your executive functions will become more stable, and you’ll find it easier to keep going.
In terms of executive function, research from 2014 suggests that the successful application of a healthy diet requires a balance of two types of behaviour. The first is the right amount of inhibitory behaviour, presumably to not eat processed and unhealthy foods. The second is the right amount of initiatory behaviour, to keep those fruits and vegetables up consistently to experience the benefits.[23]
Both of these come under the banner of executive function. Both also get easier over time.
This strategy is where setting a time destination in the future and delaying judgement until then makes the most sense.
Another way to think about this is a quote I use in the clinic a lot:
“We overestimate what we can do in a day and underestimate what we can do in a year.”
This quote articulates the effects a small dietary change can have over time. If you feel you might benefit from this, I encourage you to make a start where you can.
Why?
People with better executive function have a better quality of life.[24] It doesn’t matter if you are a teenager or a woman celebrating their sixtieth birthday. You can improve your quality of life and health by making these small changes to enhance executive function.[25]
The longer you practice these changes, the easier they become. To a point where these behaviours become so natural that they shift to other brain regions.[26]
I think this change in brain activity goes some way to articulate the whole “it takes this long to create a habit” conversation. But that is best left to neuroscience and another article.
In summary, improving goal setting, initiating behaviours to work towards those goals, saying no to things that will get those goals off track, and many other behaviours that encompass executive function all take effort.
But I hope through reading this article you have found that a small initial effort to increase your dietary consumption of fruits and vegetables will pay off, with a drastic improvement in the quality of your day and your life as a whole.
Hope it helps xx
References
[1] Cristofori I, Cohen-Zimerman S, Grafman J. Executive functions. Handb Clin Neurol. 2019;163:197-219. doi:10.1016/B978-0-12-804281-6.00011-2
[2] Will Crescioni A, Ehrlinger J, Alquist JL, et al. High trait self-control predicts positive health behaviors and success in weight loss. J Health Psychol. 2011;16(5):750-759. doi:10.1177/1359105310390247
[3] Miller HV, Barnes JC, Beaver KM. Self-control and health outcomes in a nationally representative sample. Am J Health Behav. 2011;35(1):15-27. doi:10.5993/ajhb.35.1.2
[4] Riggs NR, Spruijt-Metz D, Sakuma KL, Chou CP, Pentz MA. Executive cognitive function and food intake in children. J Nutr Educ Behav. 2010;42(6):398-403. doi:10.1016/j.jneb.2009.11.003
[5] Diamond A. Attention-deficit disorder (attention-deficit/ hyperactivity disorder without hyperactivity): a neurobiologically and behaviorally distinct disorder from attention-deficit/hyperactivity disorder (with hyperactivity). Dev Psychopathol. 2005;17(3):807-825. doi:10.1017/S0954579405050388
[6] Lui M, Tannock R. Working memory and inattentive behaviour in a community sample of children. Behav Brain Funct. 2007;3:12. Published 2007 Feb 23. doi:10.1186/1744-9081-3-12
[7] Fairchild G, van Goozen SH, Stollery SJ, et al. Decision making and executive function in male adolescents with early-onset or adolescence-onset conduct disorder and control subjects. Biol Psychiatry. 2009;66(2):162-168. doi:10.1016/j.biopsych.2009.02.024
[8] Taylor Tavares JV, Clark L, Cannon DM, Erickson K, Drevets WC, Sahakian BJ. Distinct profiles of neurocognitive function in unmedicated unipolar depression and bipolar II depression. Biol Psychiatry. 2007;62(8):917-924. doi:10.1016/j.biopsych.2007.05.034
[9] Penadés R, Catalán R, Rubia K, Andrés S, Salamero M, Gastó C. Impaired response inhibition in obsessive compulsive disorder. Eur Psychiatry. 2007;22(6):404-410. doi:10.1016/j.eurpsy.2006.05.001
[10] Barch DM. The cognitive neuroscience of schizophrenia. Annu Rev Clin Psychol. 2005;1:321-353. doi:10.1146/annurev.clinpsy.1.102803.143959
[11] Bailey CE. Cognitive accuracy and intelligent executive function in the brain and in business. Ann N Y Acad Sci. 2007;1118:122-141. doi:10.1196/annals.1412.011
[12] Oaten, Megan, and Ken Cheng. “Academic examination stress impairs self-control.” Journal of social and clinical psychology 24, no. 2 (2005): 254.
[13] Diamond A. Executive functions. Annu Rev Psychol. 2013;64:135-168. doi:10.1146/annurev-psych-113011-143750
More references
[14] Janda K, Wojtkowska K, Jakubczyk K, Antoniewicz J, Skonieczna-Żydecka K. Passiflora incarnata in Neuropsychiatric Disorders-A Systematic Review. Nutrients. 2020;12(12):3894. Published 2020 Dec 19. doi:10.3390/nu12123894
[15] Koulivand PH, Khaleghi Ghadiri M, Gorji A. Lavender and the nervous system. Evid Based Complement Alternat Med. 2013;2013:681304. doi:10.1155/2013/681304
[16] Lopresti AL, Smith SJ, Malvi H, Kodgule R. An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 2019;98(37):e17186. doi:10.1097/MD.0000000000017186
[17] Hidese S, Ogawa S, Ota M, et al. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. Nutrients. 2019;11(10):2362. Published 2019 Oct 3. doi:10.3390/nu11102362
[18] Callan C, Ladds E, Husain L, Pattinson K, Greenhalgh T. ‘I can’t cope with multiple inputs’: a qualitative study of the lived experience of ‘brain fog’ after COVID-19. BMJ Open. 2022;12(2):e056366. Published 2022 Feb 11. doi:10.1136/bmjopen-2021-056366
[19] Cohen JF, Gorski MT, Gruber SA, Kurdziel LB, Rimm EB. The effect of healthy dietary consumption on executive cognitive functioning in children and adolescents: a systematic review. Br J Nutr. 2016;116(6):989-1000. doi:10.1017/S0007114516002877
[20] Cohen JF, Gorski MT, Gruber SA, Kurdziel LB, Rimm EB. The effect of healthy dietary consumption on executive cognitive functioning in children and adolescents: a systematic review. Br J Nutr. 2016;116(6):989-1000. doi:10.1017/S0007114516002877
[21] Zhou G, Gan Y, Miao M, Hamilton K, Knoll N, Schwarzer R. The role of action control and action planning on fruit and vegetable consumption. Appetite. 2015 Aug;91:64-8. doi: 10.1016/j.appet.2015.03.022. Epub 2015 Mar 26. PMID: 25819607.
[22] https://www.chp.gov.hk/files/pdf/ncd_watch_april_2018.pdf, viewed 5th August 2022.
[23] Allom V, Mullan B. Individual differences in executive function predict distinct eating behaviours. Appetite. 2014;80:123-130. doi:10.1016/j.appet.2014.05.007
[24] Brown TE, Landgraf JM. Improvements in executive function correlate with enhanced performance and functioning and health-related quality of life: evidence from 2 large, double-blind, randomized, placebo-controlled trials in ADHD. Postgrad Med. 2010;122(5):42-51. doi:10.3810/pgm.2010.09.2200
[25] Davis JC, Marra CA, Najafzadeh M, Liu-Ambrose T. The independent contribution of executive functions to health related quality of life in older women. BMC Geriatr. 2010;10:16. Published 2010 Apr 1. doi:10.1186/1471-2318-10-16
[26] Diamond A. Executive functions. Annu Rev Psychol. 2013;64:135-168. doi:10.1146/annurev-psych-113011-143750
