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The year immediately following changeover when the Sime's physical and mental growth more than doubles and the learning rate and ability to adjust emotionally soar. To become truly proficient, channels must be trained during First Year when brain and nerves are forming and strengthening. A junct cannot disjunct after the extraordinary pliability of First Year wanes. (Exception: see Tigues)

Gens also experience the accelerated First Year growth, but since they have not developed a new sense it is not so dramatic and renSimes tend to ignore it.

(Source:  Index card file, UNTO ZEOR, FOREVER)  For a channel:  What had been done to Digen -- "stealing away" of his second and third transfers to implant conditioning that prevented junct pathways from opening.  Forced development of secondary system capacity.  Arduous exercises to gain command of his vriamic node.

(Source:  Index card file.  "First Year")  Jean says it brings intellectual maturity but not emotional maturity.  Jacqueline Lichtenberg says it varies with the individual --- natural selection weeds out those without flexibility and maturity to learn to see the world with Sime senses.

Many Second Year Simes (Madhur Sharma) who changed over young seem "almost grotesquely" mature for their age.  It's not COMMON but it is POSSIBLE for a 12 or 13-year-old to be president of a world --- and Simes allow for it.