Harm avoidance (HA) is a personality trait characterized by excessive worrying; pessimism; shyness; and being fearful, doubtful, and easily fatigued. In MRI studies HA was correlated with reduced grey matter volume in the orbito-frontal, occipital and parietal regions.[1][2]
Fatigability/Fatigability and asthenia (weakness) (HA4)
It has been suggested that HA is related to high serotonergic activity,[4]
and much research has gone into investigating the link between HA and components of the serotonin system, e.g. genetic variation in 5-HTTLPR in the serotonin transporter gene.[5]
↑Gardini, S; Cloninger, CR; Venneri, A (Jun 2009). "Individual differences in personality traits reflect structural variance in specific brain regions". Brain Res. Bull. 79 (5): 265–70. doi:10.1016/j.brainresbull.2009.03.005. PMID19480986. S2CID25490518.
12De Fruyt, F.; Van De Wiele, L. & Van Heeringen, C. (2000). "Cloninger's Psychobiological Model of Temperament and Character and the Five-Factor Model of Personality". Personality and Individual Differences. 29 (3): 441–452. doi:10.1016/S0191-8869(99)00204-4.
↑C. R. Cloninger (Autumn 1986). "A unified biosocial theory of personality and its role in the development of anxiety states". Psychiatric Developments. 4 (3): 167–226. PMID3809156.