Facial expression responsible for controlling the expression differ in each case. Voluntary facial expressions are often socially conditioned and follow a cortical route in the brain. Conversely, involuntary facial expressions are believed to be innate and follow a subcortical route in the brain. Facial recognition is often an emotional experience for the brain and the amygdala is highly involved in the recognition process. The eyes are often viewed as important features of facial expressions. Aspects such as blinking rate can possibly be used to indicate whether a person is nervous or whether he or she is lying. Also, eye contact is considered
Emerging adulthood and early adulthood OECD nations, and as a stage of development has only emerged over the past half century. It is specific to "certain cultural-demographic conditions, specifically widespread education and training beyond secondary school and entry into marriage and parenthood in the late twenties (or early thirties) or beyond". Furthermore, emerging adulthood occurs only within societies that allow for occupational shifts, with emerging adults often experiencing frequent job changes before settling on particular job by the age of 30. Arnett also argues that emerging adulthood happens in cultures that allow for a period of time between adolescence and marriage, the marker of adulthood.