PSY340H5 Lecture Notes - Child Development Stages, Intellectual Disability, Twin Study
Document Summary
The science of psychology is what people do, questions what is the norm of the behavior. In order to understand what abnormal is, we have to understand what normal is. Abnormality is defined by: statistical criteria, cultural norms, developmental milestones. One aspect of abnormal behavior is that it is infrequent in the general population. Normality implies the person doesn"t deviate much from the average trait/behavior. Statistical infrequency is used to diagnose mental retardation. Iq of 100 is considered to be normal. Iq of below 70 is classified as having mental retardation. Iq of above 130 is classifies the person as being gifted. In some cultures, having delusions and hallucinations is considered as abnormal, but with one exception that there are subsets of humans where delusions and hallucinations are considered normal (ex. Normal and abnormal can be defined according to whether developmental stages have been met by a certain age (ex.
