These changes are related to dynamic changes on the molecular level, which involve gene expression (Hof & Morrison, 2004; Hong, Myers, Magnusson, & Prince, 2008; Lu, Pan, Kao, Li, Kohane, Chan, et al., 2004; Masliah, et al., 1993; Somel, Franz, Yan, Lorenc, Guo, Giger, et al., 2009; Somel, Khaitovich, Bahn, Paabo, & Lachmann, 2006). The transcriptome of the brain, as well as of other tissues, is a dynamic system that changes throughout life, through the development of the organism and the brain in particular. Some studies have found an association between transcription and the development of the brain, and have shown the important role of gene expression in the formation of synapses and various other aspects of higher mental functioning (Diaz, 2009; Diaz, et al., 2002; Flavell & Greenberg, 2008). The changes in gene expression in the brain throughout the life-span correspond closely to the major stages of prenatal and neonatal development, the maturing and aging of the brain.
