From the very first weeks of life, infants differ in their characteristic emotional reactions, with some infants being intense and anxious, while others are easygoing and relaxed. these differences are usually explained as differences in

These differences are usually explained as differences in "temparment".

In psychology, temperament comprehensively alludes to steady individual contrasts in conduct that are naturally based and are generally autonomous of learning, arrangement of qualities and dispositions. A few specialists point to relationship of disposition with formal dynamical highlights of conduct, for example, enthusiastic perspectives, versatility, affectability to particular reinforcers and emotionality.  

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