<unk> : Originally thought to be concrete and unchanging, recent studies have found evidence that<unk>  can<unk> throughout a person's life. An important idea to keep in mind is that differences in<unk>  traits among individuals tend to stay consistent throughout fairly long periods of time. However, that doesn't mean that<unk>  traits do not<unk> during an individual's life. Gradual<unk>  to trait levels tend to happen throughout the lifetime of an individual and can become quite substantial. Trait levels can also<unk> as a result of a major event in an individual's life. To understand the<unk>  that can happen within<unk> , one must first understand it.<unk>  refers to individual differences in characteristic patterns of thinking, feeling and behaving. Every person has their own "individual differences in particular<unk>  characteristics" that separate them from others. The overall study of<unk>  "focuses on two broad areas: One is understanding individual differences in particular<unk>  characteristics... The other is understanding how the various parts of a person come together as a whole." An easier way to understand or describe<unk>  is simply to say: one's<unk>  is made up of events, circumstances, and genetics, that come together to influence the development of defining characteristics and traits. Those traits and characteristics that define someone are what the general public like to describe as<unk> . With each person having their own<unk> , there are bound to be many differences and<unk>  that confuse people.<unk>  psychologists have taken much time to search for answers and solutions to the<unk>  that can come to someone's<unk> . Although there is little research overall, there has been compelling initial evidence for<unk>  The development of<unk>  is often dependent on the stage of life a person is in, and the extent to which one's levels of characteristics, relative to their age cohort, is stable across long periods of time. Cultural and environmental influence are large factors in<unk>  trait differences.<unk> is usually seen over longer periods of time and is analogical to height, as most development occurs in the earlier stages of life and becomes more stable as one grows into adulthood. The Big Five, or Five Factor Model, is the most widely accepted form of<unk>  theory, and especially in terms of<unk>  While still uncertain, Research suggests that genetics play a role in the<unk> and stability of certain traits in a<unk> . They have also discovered environmental and situational/contextual sources affect<unk> . Some debates have pervaded the field of psychology since its beginning. One of the most debated topics has to do with the nature and development of<unk> .<unk>  psychology studies one's distinctive style of cognition, behavior, and affect. However, this concept elicits discord among psychologists as some have insisted that it does not exist, while others struggle with issues of measurement.
Personality changes
Food craving
Sedation
Irritability
Fatigue
Voice change
Mental distress
Dryness 