Adulthood 31 Psychological aspects 31 Aging 18 Adjustment (Psychology) 8 Interpersonal relations 8 Textbooks 6 Self-help techniques 4 Social aspects 4 Adult learning 3 Learning, Psychology of 3 Longitudinal studies 3 Physiological aspects 3 Age factors 2 Cognition 2 Langitudinal studies 2 Life cycle 2 Life cycle, Human 2 Counseling 1 Developmental psychology 1 Employment 1 Family 1 Married people 1 Personality and occupation 1 Psychology 1