Performing under Pressure; on the Biology, Psychology and Sociology of stress in high-performance
professions
II - ON THE PHYSIOLOGY OF STRESS




Nature selects for speed
uSpeed over accuracy
uIt matter less where you run than that you run as quickly as possible
u
uLimited time frame (5 min)
uMost negatives effects of stress are the result of turning on the system for way longer than the
approximately 5 minutes it usually takes.
Sapolsky, R. M. (2004). Why zebras don’t get ulcers: A guide to stress, stress related diseases,
and coping. In Natural History. https://doi.org/10.1002/cir.3880060119
Heitz, R. P. (2014). The speed-accuracy tradeoff: History, physiology, methodology, and behavior.
Frontiers in Neuroscience, 8(8 JUN), 1–19. https://doi.org/10.3389/fnins.2014.00150

Both the lion and the gazelle need the same acute processes to survive
u
uTransport energy (fuel + oxygen) to those parts of the body that you need to survive
uLegs
uUpper body
u
uHyper cognitive focus on the task at hand (fight or flight)
u
uDown-regulation of non-essential processes

Energy
uOxygen in-take and transport to the relevant muscle groups
uIncreased respiration rate
uIncreased blood pressure / increased heart rate
u
uRelease of glucose from glycogen stores and transport to the relevant muscle groups
uCortisol
uIncreased blood glucose levels
uIncreased blood pressure / increased heart rate
u

Important cognitive changes
uMild stress
uEnhanced cognitive function; implicit memory & declarative tasks
uEnhanced task oriented focus
u
uHigh acute or chronic stress
uImpairs the formation of complex memories: enhances implicit memory
uRepetitive tasks
Sandi, C. (2013). Stress and cognition. WIREs Cogn Sci, 4(June). https://doi.org/10.1002/wcs.1222

Downregulated functions
uGrowth
u
uReproduction
u
uDigestion
Yamamora, D. L. R., & Reid, R. L. (1990). Psychological stress and the reproductive system.
Seminars in Reproductive Endocrinology, 8(1), 65–72. https://doi.org/10.1055/s-2007-1021424
Toyoda, A., Iio, W., Matsukawa, N., & Tsukahara, T. (2015). Influence of chronic social defeat
stress on digestive system functioning in rats. Journal of Nutritional Science and Vitaminology,
61(3), 280–284. https://doi.org/10.3177/jnsv.61.280
Oroian, B. A., Ciobica, A., Timofte, D., Stefanescu, C., & Serban, I. L. (2021). New Metabolic,
Digestive, and Oxidative Stress-Related Manifestations Associated with Posttraumatic Stress
Disorder. Oxidative Medicine and Cellular Longevity, 2021. https://doi.org/10.1155/2021/5599265

Processing stimuli; the hardware
uA stimulus is detected by one of our senses
uThe amygdala relays signals if the stimulus is threatening
uLocus coeruleus (Norepinephrine)
uHypothalamic adrenal axis (Cortisol)
uVentral tegmental area (Dopamine)
uMedial prefrontal cortex (is this really a problem?)
u
u

Autonomic nervous system
u
uSympathetic nervous system
u
u
uParasympathetic nervous system

(nor-)adrenaline / (nor-)epinephrine
uSetting the system up for movement
uBlood pressure / heart-rate
uRespiration rate
u Task related focus and memory
uHeightened alertness & stressor related memory
uThree behavioural stages of nor-adrenaline
uMovement
uErratic movement (panic)
uShutdown
u
Ross, J. A., & Van Bockstaele, E. J. (2021). The Locus Coeruleus- Norepinephrine System in Stress
and Arousal: Unraveling Historical, Current, and Future Perspectives. Frontiers in Psychiatry,
11(January), 1–23. https://doi.org/10.3389/fpsyt.2020.601519

Cortisol
uRelease glucose (fuel) from glycogen stores
uHighest in the morning
uNightmares
uInteraction with nutrition
u
uSuppress inflammation
u
uBlood pressure
u

What does dopamine do to the stress response
uDopamine: the great motivator (NO, it does not do reward!!)
u
uTraining
u
uUncertainty
u
u
Schultz, W. (2002). Getting formal with dopamine and reward. Neuron, 36(2), 241–263.
https://doi.org/10.1016/S0896-6273(02)00967-4