This 2016 Italian human review considered the lower brain’s contributions to an individual’s behavior and temperament:
“In evidencing associations between personality factors and neurobiological measures, it seems evident that the cerebellum has not been up to now thought as having a key role in personality.
Cerebellar volumes correlate positively with novelty seeking scores and negatively with harm avoidance scores. Subjects who search for new situations as a novelty seeker does (and a harm avoiding does not do) show a different engagement of their cerebellar circuitries in order to rapidly adapt to changing environments.
Cerebellar abilities in planning, controlling, and putting into action the behavior are associated to normal or abnormal personality constructs. In this framework, it is worth reporting that increased cerebellar volumes are even associated with high scores in alexithymia, construct of personality characterized by impairment in cognitive, emotional, and affective processing.”
The full paper wasn’t freely available, but a list of the 173 references was. 17 references were of alexithymia, also mentioned in the title.
One freely available reference was The embodied emotion in cerebellum: a neuroimaging study of alexithymia, a 2014 study performed by these same authors, which found:
“Alexithymia scores were linked directly with cerebellar areas and inversely with limbic and para-limbic system, proposing a possible functional modality for the cerebellar involvement in emotional processing.
The increased volumes in Crus 1 of subjects with high alexithymic traits may be related to an altered embodiment process leading to not-cognitively interpreted emotions.”
“Alexithymia scores” referred to one of the methods used to characterize alexithymia symptoms, self-reported answers to questionnaires such as this one. Sample questions from the questionnaire used by the referenced study are:
- “I am often confused about what emotion I am feeling
- It is difficult for me to reveal my innermost feelings, even to close friends”
The questionnaire mainly engages a person’s cerebrum. The person may recall emotions, and form ideas as framed by each question. Then they’ll describe these ideas in terms of a scaled answer.
Cerebral answers may provide historical contexts for feelings. However, the person’s cerebellum and other brain areas aren’t necessarily engaged by the diagnostic questionnaire.
Without this engagement, the person may not experience feelings when providing answers about feelings. The answers may be more along the lines of “This is what I think I should be feeling” or “This is what I think I should tell the researchers about what I think I should feel.”
- Can a questionnaire accurately determine associations among engaged and unengaged brain areas?
- What can be done regarding “impairment in cognitive, emotional, and affective processing?”
- What’s the lower brain’s “involvement in emotional processing?”
- How does the lower brain shape a person’s behavior and traits?
- When and where in an individual’s lifespan does their cerebellum develop?
http://link.springer.com/article/10.1007/s12311-015-0754-9 “Viewing the Personality Traits Through a Cerebellar Lens: a Focus on the Constructs of Novelty Seeking, Harm Avoidance, and Alexithymia”