Psychiatry and Neuroscience Update
pp 157-179
The Role of Iron and Other Trace Elements on Mental Development and Cognitive Function
Silvia Izquierdo-Álvarez et al
Abstract
In this chapter we review the effect of some trace elements. Consequences of exposure or modification of the levels of iron, lead, methylmercury, mercury, cadmium, manganese, arsenic, and copper on the central nervous system (CNS) and learning and cognition will be discussed. We review the effects of iron deficiency (ID) and anemia on cognitive function and the relationship between its statuses on developmental outcome and the state of the adult brain. The iron needs of the brain vary depending on the stage of the life cycle and the cell types. ID has been reported to have a role in brain development and some trace elements are routinely involved in metabolic processes and oxidation-reactions in the CNS which could have a possible effect on cognitive functions. Behavioral and cognitive adverse effects caused by exposure to lead by the fetus and infant are discussed, as well as fetal and infant exposure to high concentrations of methylmercury and cadmium on CNS development and their cognitive consequences. A significant correlation between elevated levels of cadmium and lead and decreased verbal development and lower IQ has been shown in children. The potential effects associated with the accumulation of manganese in the CNS decreasing levels of neurotransmitter. Arsenic exposure can produce neurocognitive deficits in children. Dysregulation of iron homeostasis is also a critical feature in Alzheimer disease (AD), Parkinson disease (PD), Friedreich ataxia (FA), and neurodegeneration with brain iron accumulation. Copper toxicity and zinc deficiency are associated with cognition loss and AD. Consequently, we consider an update on these issues necessary.
