Functional Ensemble of Temperament

Medications can adjust the release of brain neurotransmitters in cases of depression, anxiety disorder, schizophrenia and other mental disorders because an imbalance within neurotransmitter systems can emerge as consistent characteristics in behaviour compromising people's lives. All people have a weaker form of such imbalance in at least one of such neurotransmitter systems that make each of us distinct from one another. The impact of this weak imbalance in neurochemistry can be seen in the consistent features of behaviour in healthy people (temperament). In this sense temperament (as neuro-chemically-based individual differences) and mental illness represents varying degrees along the same continuum of neurotransmitter imbalance in neurophysiological systems of behavioural regulation. In fact, multiple temperament traits (such as Impulsivity, sensation seeking, neuroticism, endurance, plasticity, sociability or extraversion) have been linked to brain neurotransmitters and hormone systems. ==Development of the FET model==

The architecture of the Functional Ensemble of Temperament (FET) was developed by Trofimova as the Compact version of the Structure of Temperament Questionnaire (STQ-77) in 1997–2007. The differentiation between the rows of the FET inherits the activity-specific approach to the structure of temperament proposed by Rusalov in mid-1980s. According to this approach, the traits of temperament (and behavioural regulation) related to motor-physical, social-verbal and mental aspects of activities are based on different neurophysiological systems and should be assessed separately (so you can see a separation of traits into 3 rows related to these 3 types of activities). The 3-column structure of the FET framework follows Alexander Luria theory of three functional neuroanatomic systems (sensory-informational, programming and energetic) and is in line with functional constructivism approach. This approach views all behaviour as being constructed and generated anew based on individual's capacities and demands of the situation or knowledge about causes of natural processes (a trait named as Sensitivity to Probabilities). In February 2018, by the suggestion of Dr Marina Kolbeneva (Institute of Psychology, Russian Academy of Sciences) the scale Self-Confidence was renamed as the scale of dispositional Satisfaction. ==Overview of the model==

The final STQ-77/FET framework classifies temperament traits and their neurochemical biomarkers into 12 components: nine components regulating the formal functional aspects of behaviour (energetic, dynamic and orientational) each assessed in three domains (intellectual, physical and social-verbal); also three components related to emotionality (Neuroticism, Impulsivity and Satisfaction (Self-Confidence)) (see Figure) The FET framework summarized existing literature showing the nine non-emotionality traits are regulated by the monoamines (MA) (noradrenalin, dopamine, serotonin), acetylcholine and neuropeptide systems, whereas the three emotionality-related traits emerge as a dysregulation of opioid receptors systems that have direct control over MA systems. Importantly, the FET model suggests that there is no one-to-one correspondence between the neurotransmitter systems underlying temperament traits (or mental disorders) but instead specific ensemble relationships between these systems emerge as temperament traits. The interplay within hormonal systems and its interaction with serotonin also appeared to be a factor is social emotions, such as shame and guilt == FET model and classifications of psychiatric disorders ==

FET framework was proposed to simplify classifications of psychiatric disorders (DSM, ICD) using 12 functional aspects of behaviour that this model highlights. Clinical studies showed good differential power of the FET framework for various diagnoses of psychopathology. For example, depressed people had low endurance and psychomotor slowdown in their temperament profiles. In contrast to them, patients with Generalized Anxiety Disorder had higher impulsivity and neuroticism. FET-developers suggested that every symptom in DSM/ICD diagnoses can be mapped into a specific FET code reflecting a disregulation within well-documented neurochemical systems. ==References==