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
 Speed over accuracy
 It matter less where you run than that you run as quickly as possible
 Limited time frame (5 min)
 Most 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
 Transport energy (fuel + oxygen) to those parts of the body that you
need to survive
 Legs
 Upper body
 Hyper cognitive focus on the task at hand (fight or flight)
 Down-regulation of non-essential processes
Energy
 Oxygen in-take and transport to
the relevant muscle groups
 Increased respiration rate
 Increased blood pressure /
increased heart rate
 Release of glucose from glycogen
stores and transport to the
relevant muscle groups
 Cortisol
 Increased blood glucose levels
 Increased blood pressure /
increased heart rate
Important cognitive changes
 Mild stress
 Enhanced cognitive function; implicit memory & declarative tasks
 Enhanced task oriented focus
 High acute or chronic stress
 Impairs the formation of complex memories: enhances implicit memory
 Repetitive tasks
Sandi, C. (2013). Stress and cognition. WIREs Cogn Sci, 4(June). https://doi.org/10.1002/wcs.1222
Downregulated functions
 Growth
 Reproduction
 Digestion
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
 A stimulus is detected by one of
our senses
 The amygdala relays signals if the
stimulus is threatening
 Locus coeruleus (Norepinephrine)
 Hypothalamic adrenal axis
(Cortisol)
 Ventral tegmental area
(Dopamine)
 Medial prefrontal cortex
Autonomic nervous system
 Sympathetic nervous system
 Parasympathetic nervous system
(nor-)adrenaline / (nor-)epinephrine
 Setting the system up for movement
 Blood pressure / heart-rate
 Respiration rate
 Task related focus and memory
 Heightened alertness & stressor related memory
 Three behavioural stages of nor-adrenaline
 Movement
 Erratic movement (panic)
 Shutdown
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
 Release glucose (fuel) from glycogen stores
 Highest in the morning
 Nightmares
 Interaction with nutrition
 Suppress inflammation
 Blood pressure
What does dopamine do to the
stress response
 Dopamine: the great
motivator (NO, it does not do
reward!!)
 Training
 Uncertainty
Schultz, W. (2002). Getting formal with dopamine and reward. Neuron, 36(2), 241–263. https://doi.org/10.1016/S0896-6273(02)00967-4