Trace elements are found in the living organism in small (trace) amounts and are mainly essential for living functions. Essential trace elements are in humans the chromium (Cr), cobalt (Co), copper (Cu), fluorine (F), iodine (I), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), zinc (Zn), and questionably the boron (B) and vanadium (V). According to the biopsychosocial concept, mental functions have biological underpinnings, therefore the impairment of certain neurochemical processes due to shortage of trace elements may have mental consequences. Scientific investigations indicate the putative role of trace element deficiency in psychiatric disorders such in depression (Zn, Cr, Se, Fe, Co, I), premenstrual dysphoria (Cr), schizophrenia (Zn, Se), cognitive deterioration/de-mentia (B, Zn, Fe, Mn, Co, V), mental retardation (I, Mo, Cu), binge-eating (Cr), autism (Zn, Mn, Cu, Co) and attention deficit hyperactivity disorder (Fe). At the same time, the excess quantity (chronic exposure, genetic error) of certain trace elements (Cu, Mn, Co, Cr, Fe, V) can also lead to mental disturbances (depression, anxiety, psychosis, cognitive dysfunction, insomnia). Lithium (Li), being efficacious in the treatment of bipolar mood disorder, is not declared officially as a trace element. Due to nutrition (drinking water, food) the serum Li level is about a thousand times less than that used in therapy. However, Li level in the red cells is lower as the membrane sodium-Li countertransport results in a Li efflux. Nevertheless, the possibility that Li is a trace element has emerged as studies indicate its potential efficacy in such a low concentration, since certain geographic regions show an inverse correlation between the Li level of drinking water and the suicide rate in that area.

Mental flexibility enabling shifts from the usual prepotent behaviour to new strategies and solutions is a significant factor in the successful adaptation to the changing environment. Components of mental flexibility comprise attention, salience detection, inhibition, working memory and switch processes which can be measured by neurocognitive tests. Data derived from examinations by the methods of cognitive neuroscience can be compared to the features, observed under resting state and during task performance, of brain structures and functions. Studying central nervous system correlates of mental flexibility by imaging, neurobiological, and pharmacological techniques revealed that certain cerebral regions (prefrontal cortex, anterior cingulate and insula, striatum, inferior parietal lobule) with their network connectivities, and some neurotransmitters (e.g. dopamine) have profound roles in this respect. Flexibility shares some similarities with artistic/scientific/everyday creativity and openness as a personality trait and this is also reflected in neurobiological parameters. According to precedents in art history, the public reception and acceptance of nonconform avant-garde artistic products are also dependent on flexibility and openness. Alterations of mental flexibility have been found in diseases (psychiatric and others), and in stress situations. Although flexible switch is generally considered as positive and beneficial, under certain conditions advantages might arise from keeping stability maintaining customs, conventions, and traditions. Orv Hetil. 2017; 158(45): 1771–1786.

Depending on the personal attitude toward a given style and performance, music can influence mental activities such as emotion, mood, motivation, psychomotor tempo and possibly cognition. Experimental data indicate that music can alter physiological parameters of somatic functions (blood pressure, heart rhythm, peripheral blood flow, respiration). However, efforts are taken in medicine and neuroscience to decipher brain physiological and morphological correlates in processing or performing music. Modern imaging techniques brought a significant advance in this respect. It appears that there is no single music center in the brain, but depending on the components (melody, rhythm) of the music, more cerebral areas with strong network connections participate in that. Important regions are the upper temporal area (primary, secondary, tertiary auditory cortex), and parts of the frontal and parietal lobes, limbic system, and cerebellum. Beyond the above aspects, medicine joins to music in the field of music therapy. Meta-analyses of controlled studies show that music can be suitable to decrease stress, anxiety, and depression in various disease groups (cardiovascular, oncological, mental) and in medical examinations (surgical, urological, cardiac catheterization). Improvements were observed in motor, cognitive and psychosocial functions after music interventions in stroke rehabilitation. The links between mood disorders and creativity in music belong to medicine as well, where eminent composers can be mentioned, and also the examples of scholar and practitioner physicians playing or composing music superbly. Orv Hetil. 2019; 160(11): 403–418.

Suspicious thinking in given situations can be useful and helps the adaptation as events occurring in the world also corroborate this. Factors participating in the development of paranoia can be listed as psychodynamic (projection), salience attributional, neurobiological (dopamine), impaired perceptual (hearing loss), sociocultural (minority, pseudocommunity), self-esteem (worrying, depression, mania), and cognitive (jump-to-conclusion) mechanisms. Along the spectrum of thinking, from the mild to the severe, enhanced worrying, salience attribution, overvalued concepts, suspicion/mistrust, paranoid ideations, and crystallized delusions may occur with different contents. In recent years intensive research has been started to reveal the presence of subclinical paranoid thoughts in the general population. Applying various screening methods developed for this purpose (delusions inventories, psychometric tests, virtual reality laboratory) it has been found that suspicious/mistrustful ideations are fairly common in nonclinical samples and some of these are comparable to that seen in patient population. From the larger occurrence of milder forms to the smaller frequency of more severe delusional thoughts the whole hierarchical phenomenon can be described as a ‘paranoia pyramid’. Based on this everyday paranoid thinking style lurking in people, it may well be that ‘our life is delusional’. Orv. Hetil., 2016, 157(50), 1979–1988.