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.
The amygdala and hippocampus are two parts of the limbic system of the brain. Both of these parts have primary functions that relate to memories and reactions to emotional aspects. These two parts, as part of the limbic system as a whole, deal with how the human brain processes these emotions and memories.he amygdala and hippocampus rely on each other to form their individual functions. Responses to stimuli are regulated by the amygdala and those responses are then used by the hippocampus in the formation of both short-term and long-term memories.