In such a deprived environment, the part of the infant’s neuroendocrine system known as the HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS is likely to be repeatedly activated during this critical part of his/her development due to a variety of stressors (e.g. by sensing the mother’s anxiety, not being sufficiently soothed when in distress etc).
WHAT IS THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS?
The HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS is a major part of the neuroendocrine system that controls the infant’s stress response. The repeated activation the HPA axis undergoes over time, due to the stressed mother’s inattentiveness (this is not to say, of course, all stressed mothers are inattentive; it only applies to mothers who are so severely stressed that it significantly impairs their maternal functioning), has the effect of signalling to the infant that s/he is growing up in a dangerous environment.
Under such conditions, the HPA axis can become highly sensitized to both real and perceived threats. In other words, the infant’s fear response becomes very easily triggered due to the HPA axis becoming oversensitive / over-reactive.
Whilst this exaggerated fear response acquired during infancy would have been of evolutionary adaptive value to the future lives (i.e. childhood and adulthood) of our ancestors living in physically dangerous environments, it has no such adaptive value as far as the modern-day infant’s future life is concerned; indeed, it can lead to serious problems as we shall see below.
WHAT ARE THE POSSIBLE ADVERSE EFFECTS OF HAVING AN OVER-SENSITIVE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS?
Having an HPA axis that is, in effect, constantly on red-alert, may have myriad adverse, long-term effects. These include :
- A damaged immune system (leading to an increase in the likelihood of suffering from a variety of diseases, including cancer).
- Impairment to cognitive functioning (e.g. loss of neurons in the hippocampus (a region of the brain involved with memory function)
- Increased likelihood of psychiatric conditions (e.g. anxiety and depression)
- Perceiving danger to exist where, objectively, it does not exist / over-estimating risks/dangers
- Less ‘mental energy’ (being constantly fearful and anxious is debilitating, demoralizing and enervating) for positive activities (e.g. play, creativity and building healthy relationships)
Important note: Although the damage done to the infant happens very early in life, many of the problems that such damage results in may not become apparent until very much later in, and, without effective therapeutic intervention, may even persist throughout the lifetime.
David Hosier BSc Hons; MSc; PGDE(FAHE).