Melasma Causes. Melasma is usually caused by the sun, hormones in birth control pills, hormone replacement therapy, medications and pregnancy. When Melasma is caused by pregnancy it is called chloasma. In some women, when the skin is exposed to sunlight, brown blotches of excess pigment form due to the interaction with hormones or chemicals. Melasma is believed to be hereditary and woman with darker skin tones tend to be more at risk for this disorder.
Some research suggests that the hippocampus may participate only in consolidation processes lasting a few years. The entorhinal cortex, on the other hand, gives evidence of temporally graded changes extending up to 20 years, suggesting that it is this region that participates in memory consolidation over decades. The entorhinal cortex is damaged in the early stages of Alzheimerâs disease.
Limbic system structures that process emotion and memory are the amygdala complex, the hippocampus, and the thalamus and hypothalamus. 1  Amygdala complex .This is the principal limbic system structure involved in processing the emotional content of behavior and memory.n effect, the shifts in the body/brain levels of these molecules allocate our emotional energyâwhat we do, when we do it, and how much energy we expend. At the cellular level, peptides synthesized within one cell attach to receptors on the outside of another, sparking increased or decreased cellular actions.