1. Introduction to Life-Span Development (Part 1)

Welcome to my series for the next module. This module is about how a human develops from birth to old age. It helps me to understand myself and others better. In human development, there are three major processes: cognitive, biological, and socioemotional.

This first post is part 1 of Study Unit 1. This unit is big, the next post will focus on the development of babies.

There are 8 periods in life-span development.
Pre-natal: Conception to birth
Infancy: Birth – 18-24 months
Early childhood: 2-5 years
Middle and Late childhood: 6-11 years
Adolescence: 10-12 to 18-21 years
Early adulthood: 20s and 30s
Middle adulthood: 35-45 years to 60s
Late adulthood: 60s and 70s

Although, age is relative. We have heard stories of how an elderly man or woman ran a full marathon, or a young boy or girl entering university. So, what is age? Age can be defined in four ways. Chronological (time), biological (biological health), psychological (adaptive capacity), and social (roles and expectations).

There are eight key principles of the life-span approach.
1. Development is Lifelong. (It does not stop at adulthood, people continue to develop)
2. Development is Multidimensional. (It covers everything, not just in physical or cognitive)
3. Development is Multidirectional. (Areas can go up and down, an older person grows in wisdom but decreases in processing speed)
4. Development is Multidisciplinary. (Different fields are interested in how humans develop)
5. Development is Pliable or Plastic. (This goes lower as we get older, but adults are still able to maintain certain functions when trained)
6. Development is Contextual. (Where the individual is in can affect development. 3 sources of context: Normative age-graded influences, normative history-graded influences, non-normative influences)
7. Development involves Growth, Maintenance, and Regulation. (Younger ones will have more growth, but as they get older, they are more about maintenance and regulation)
8. Development is Co-construction of Biology, Culture and Individual. (These 3 areas have inter-dependence)

Out of which, 3 developmental issues continue to be debated.
1. Nature vs nurture (What affects a person more, the environment or their genetics?)
2. Continuity vs discontinuity (Is development a gradual change, or divided into distinct stages?)
3. Stability vs change (As we grow older, will we remain or change?)

It is interesting to know that from the life-span perspective, there is no “crucial” age group, whereas, in the early childhood field, it is widely acknowledged that the early years are fundamental to a person’s development.

Going back to context, there are 3 sources of context.

Normative age-graded influences are what everyone goes through at the same age, such as puberty and menopause. It can also be about the country, such as in Singapore, where the age for Primary school is 7, and the age to collect CPF savings is 65.
Normative history-graded influences happen when people go through historical events, such as the 911 terrorist attacks. Recently, the COVID-19 is also one such influence. History will look back and recall this pandemic that affected the whole world.
Non-normative influences are unique to individuals. They do not happen for everyone, but it certainly affects that person in a great way.

Several theories guide us in understanding more about human development. Freud’s Psychoanalytical theory, Erikson’s Psychosocial Theory, Piaget’s Cognitive Development Theory, Vygotsky’s Sociocultural Cognitive theory, the Information-Processing theory, Skinner’s Operant Conditioning, Bandura’s Social Cognitive Theory, Ethological theory, and Bronfenbrenner’s Ecological theory.

However, we should take an eclectic approach, as each theory does not cover the whole aspect of being a human. Knowing how a child constructs knowledge by himself does not help him to develop social skills, or learn without the presence of an adult offering operant conditioning.

Theories are coherent and have been proven by assumptions or observations. Research is a way that people can be observed, and data is then collated.

There are 3 basic forms of research: Descriptive Research, Correlational Research, and Experimental Research.

Descriptive Research involves observing and recording behaviours. It includes Observation, Surveys and interviews, Standardised test, Cast study, Life-history record, and Physiological measures.
Correlational Research is used to compare at least 2 events of characteristics, to evaluate their relationships.
Experimental Research is when a variable that can affect behaviour is changed while the other variables remain fixed, this is to access the effects.

In research, time-span is a concerning factor. These are the approaches that relate age to a changing variable.

The cross-sectional approach is when people of different ages are studied, and a longitudinal approach is about studying the same people over long periods. The longitudinal approach is expensive, time-consuming, and participants tend to drop out after a long time. The sequential approach is a combination of both. A group of mixed ages are studied, then they are moved to a longitudinal study, then, later on, another group is added. The third approach is more time consuming but it covers areas that the first two are unable to. Cohort effect is where a group of people who are born at the same point in history are studied.

But regardless of the approach, there are 4 ethical issues that researchers have to take note: Informed consent (participants must know what they are involved in and whether there are any risks for taking part), Confidentiality (sometimes anonymous), Debriefing (of the purpose and methods used), and Deception (sometimes revealing too much to the participants will affect the study, so they will only know of the nature of the study asap after it is over).

Biasness can also occur during studies, there are 5 guidelines to follow: Distinguish between group results and individual needs, Do not over-generalise from a small sample, Look for answers beyond a single study, Do not attribute causes where none have been found, Evaluate the source of the information about life-span development.

References
Kong, G. S. (2020). SWK104 Human Growth and Life-Span Development (Birth to Adolescence) Study Guide (5CU). Singapore.

Santrock, J. W. (2019). Life-span Development (17th Edition). New York: McGraw-Hill Education.