Emotions are developed over a period of time as a response to our day to day interactions and experiences with the world. These positive/negative interactions and experiences can be visual or physical or psychological or all of it.
According to renowned psychology researchers David Watson and Lee Anna Clark (1994) at the University of Iowa:
what we refer to as emotion is essentially a psychophysiological response, whether to external stimuli or as a result of mental processes;
a pattern of autonomic changes;
a distinct subjective feeling state.
Emotions have a long lasting effect on us i.e., whenever we encounter an Emotional-Trigger, we are reminded instantly how we felt and how it have affected us physically/ psychologically in the past in a similar situation.
Fictional Example ( with reference to sitcom - The Big bang theory )
Synopsis:
Sheldon reluctant about moving forward in his relationship and Amy being his smart girlfriend taps his emotions and manipulates him.
Observation:
Here we see Sheldon based on his childhood experiences has developed various emotions over things such as food, music and so on.
Take Away:
And so to answer the question, We have strong emotions associated with things that are important to us such as,
First crush
First Girlfriend/Boyfriend
First pet
Withdrawing your first salary
First kiss
That Heart break
Peeling dry glue off your fingers
Later on (even after many years ) when we encounter similar or related situation(physical/ psychological)these emotions are triggered with same intensity.
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