Biology as Operating System: How Your Physiology Sets Your Cognitive Parameters

If your PC is running slowly and occasionally giving you errors the most common fix is either a soft reset (restart the computer) or a hard reset (reinstall your operating system and wipe it clean). Sometimes the soft reset works but often the operating system has become corrupted, bloated, and has reduced functioning. In an ideal world, the PC has such regular maintenance and is regularly switched off that a hard reset is never required but often times this maintenance isn’t as often as optimal and the operating system begins to fail. The same is true of your cognition and mental health. In an ideal world the maintenance has been regular and you engage in ‘soft resets’ regularly to keep the operating system fresh but for the modern executive this is getting harder and harder. The research is this area shows that your biology and physiology sets parameters within which your cognition and mental health can operate.

Welcome to the second edition on my ‘Psychology follows physiology’ manifesto. We started last week with an overview, this week we are discussing the first principle. Biology as your operating system.

Physical States, Mental Performance: Embodied Cognition

Embodied cognition (also known as Embodied Cognition Theory or ECT) was once considered fringe and emerging but now enjoys prominence and a large body of research and is considered mainstream neuroscience. Central to the idea of embodied cognition is the idea that physical states directly influence cognitive processes through measurable pathways. And the research supports this.

A recent meta-analysis of the topic of ‘embodied learning’ found that “embodied learning significantly improved learning performance and significantly reduced cognitive load”. Another recent study showed that “performance of certain body postures and movement could facilitate cognitive restructuring” and similarly this study found that participants “who adopted an upright posture showed a more positive general mood and higher processing speed compared to those in stooped postures”.

HRV: Your Cognitive Capacity Indicator

We discussed HRV, or heart rate variability, in the last edition of the newsletter. HRV is simple in that it is just the measure of variation in the time interval between consecutive heartbeats, measured in milliseconds. It is considered an indirect readout of the balance between your sympathetic and parasympathetic nervous systems. A higher HRV generally reflects healthy function, inherent self-regulatory capacity, adaptability, and resilience (for a review on the topic see here).

Research has found that HRV is a powerful predictor of ones cognitive capacity. This systematic review from 2019 which looked at the findings of 20 studies containing over 19,000 participants found that HRV is predictive of performance in a range of cognitive domains. For example, the study found lower HRV was associated with worse global cognitive performance, that “people with higher HRV levels demonstrate a better ability to control over memory and a better ability to suppress unwanted memories”, lower resting HRV was predictive of worse attentional performance, that “lower HRV predicted poorer performance on tasks involving executive functioning”, and that “HRV is strongly associated with the neuronal activity of the prefrontal cortex, which in turn regulates the executive functions”.

HRV is emerging as not just important for tracking cardiovascular and athletic ability but also cognitive ability, the research shows HRV puts a biological ceiling of performance on your brain. This means your HRV reading before a critical decision can predict your cognitive capacity for that task. A higher HRV doesn’t guarantee high cognitive performance but a low HRV certainly prevents it.

Cortisol: The Performance Hormone Architecture

When people think burnout and stress they usually think cortisol (although cortisol gets a bad rap it’s actually critical for peak performance, I covered this here). Cortisol exhibits an ‘Inverted U’ concentration relationship with performance where there is a sweet spot for peak performance and too much or too little impairs it. Cortisol is a measurable biological hormone that directly affects brain structure and function.

Cortisol is deeply intwined with the prefrontal cortex (PFC). The PFC has a high concentration of receptors for cortisol and therefore it’s not surprising that elevated cortisol levels impact the PFC profoundly and can impact performance. Some examples:

• Chronic stress and elevated cortisol levels cause dendritic retraction and reduced spine density in PFC
• Chronic cortisol elevation impairs executive function
• Cortisol impairs memory through actions on the PFC
• Chronic stress and elevated cortisol levels can have detrimental effects on the structure and function of the PFC, impairing its ability to make optimal decisions

As we saw in my cortisol deep dive (here) the cortisol awakening response is an important physiological contributor to waking cognitive performance. This study has found that the cortisol awakening response sets daily cognitive parameters through brain network optimisation. Specifically, the cortisol awakening response promotes brain preparedness via improved PFC and hippocampal efficiency.

Temperature: The Chemical Reaction Controller

Our body and physiology is the result of millions of chemical reactions occurring throughout the body whether it’s muscles breaking down ATP to contract and create and heart beat or enzymes putting amino acids together to make proteins. Most of these reactions proceed at different rates and, sometimes, in different ways depending on the temperature they are carried out at. Therefore it is not surprising that body temperature impacts cognition.

This review found that:

• Lower ambient/skin temperatures evoke a need for social connection
• Higher ambient/skin temperatures facilitate notions of others as closer/more sociable
• Above-average ambient temperatures are associated with increased conflicts and an increase in the incidence of mental disorders and suicide.

It also found that mild hypo or hyperthermia was generally associated with impairments in cognitive performance, anxiety, and irritability.

Temperature is a powerful regulator of our performance and is affected by things such as office temperatures and office attire.

Glucose: Your Brain's Energy Infrastructure

We’ve all experienced the effect of low glucose on our mental state. The term “hangry” describes hungry-angry and I am sure we all know a person or two that fit’s that description. Research has found that generally low blood sugar is associated with impaired attention, memory, and executive function as well as increased levels of anxiety, irritability (hello hangry), fatigue, and negative affect.

We saw last edition the impact of glucose on decision making and why you should book morning doctor appointments. Make sure you're not running on low-glucose ahead of the next big meeting, flow session, or high stakes decision. Keep a handful almonds nearby for emergencies like this.

The Interconnected Performance Network: Systems Thinking

Peak cognitive performance doesn’t exist as a vacuum in your consciousness. Due to the scarcity our Sahara dwelling ancestors experienced evolution shaped the brain to be an efficiency machine prioritising survival over all else. For that reason, the brain is deeply connected to the physiological state of the entire body and when aberrations are detected cognitive luxuries such as planning, creativity, and deep thinking are curtailed to ensure survival instincts go unaffected.

Recognising and optimising this reality is the first step to unlocking true sustainable peak performance. Recognising that the human body operates as interconnected network of systems and that these physiological variables influence cognitive performance through complex, non-linear relationships is the base layer of the pyramid. Everything else builds on this. But like a pyramid, the base layer needs to be incredibly robust to support what goes on top and weaknesses in this area will ensure the structure topples.

Your breathing patterns influence your HRV, which affects your prefrontal cortex function, which impacts your decision-making capacity. These aren't separate systems you can optimise independently.

Physiology is the source code of peak performance.

Engineering Your Biological Foundation

So what does this all mean? It means to build a truly sustainable system for peak performance we need to get the base layer right. This means:

• Real-time monitoring: such as HRV and resting heart rate tracking
• System maintenance: Sleep, hydration, and stress management as foundational requirements
• Intervention hierarchy: Physiological optimisation before psychological strategies, more on this pillar next week

These parameters provide objective feedback loops for optimisation of the base layer. Then we can layer the psychology in. This represents a fundamental shift from psychology-first to physiology-first performance optimisation. Instead of trying to think your way to peak performance, you engineer it through biological systems first.

Next week we will talk about the second principle of the ‘Psychology Follows Physiology’ system we use at Second Summit Consulting - Intervention Hierarchy and why starting with physiological foundations produces longer lasting, more stable improvements.

Remember, personality doesn’t scale, biology does. We might all be different and unique combinations of personality traits (just look at Myers-Briggs, DiSC etc). But at the end of the day dopamine, cortisol, noradrenaline, they all largely do the same thing in my brain as they do in yours.

Till next week.