Developmental Psychology and Biological and Cognitive Perspectives

Development is the individual change-process from conception to death characterized as normative, non-reversible, sequential, and relatively stable.
Cephalo-caudal principle: Growth begins at the head and proceeds downward.
Proximo-distal principle: Motor skill development starts at the center of the organism and radiates outwards.
Orthogenetic principle: Proposed by Heinz Werner $1890-1964$ Development moves from simple to complex; ontogenesis recapitulates phylogenesis.
Growth vs. Maturation: Growth is physical, while maturation (as per Jerome Bruner) involves mentally and emotionally adult behavior or physical completion.

Antagonistic pleiotropy hypothesis: Proposed by George C. Williams in $1957$ Suggests that traits benefiting young organisms can become deleterious later in life, leading to aged phenotypes.
PILESS Framework: Areas of development include Physical, Intellectual, Language, Emotional, Social, and Spiritual.

Subcortical regions responsible for reflexes (e.g., spinal cord Moro reflex) develop before cortical regions.
Developmental Milestones:
- Neurulation: $18-24\,\text{prenatal days}$
- Cell migration: $6-24\,\text{prenatal weeks}$
- Myelination: $-2\,\text{months}$ to $5-10\,\text{years}$
- Synaptogenesis: $-3\,\text{months}$ to $15-18\,\text{years}$
Type of Experiences:
- Experience-expectant: Essential typical human experiences required for normal development (e.g., visual stimulation).
- Experience-dependent: Growth resulting from specific learning experiences varying by individual and culture.
Neural Darwinism: Proposed by Gerald M. Edelman $1929-2014$ Neurons and connections follow a "use it or lose it" principle of pruning and strengthening.

Sensorimotor Stage: $0-2\,\text{years}$ Focuses on sensations and movements; includes object permanence.
Preoperational Stage: $2-7\,\text{years}$ Symbolic thinking and pretend play; characterized by egocentrism.
Concrete Operational Stage: $7-11\,\text{years}$ Logical thinking about concrete events and understanding conservation.
Formal Operational Stage: $12+\,\text{years}$ Abstract reasoning and hypothetical problem-solving.

Egocentrism: Inability to see others' points of view. Piaget used the "three mountains test," while Martin Hughes $1975$ used the "policeman dolls test" to show children lose egocentrism by $4\,\text{years}$
Animism: The belief inanimate objects have feelings, declining in four stages until $12\,\text{years}$
Theory of Mind: Ability to attribute mental states to self and others. Milestones include Protoimperative and Protodeclarative pointing at $8-9\,\text{months}$
Theory of Mind Stages: Understanding wanting, thinking, seeing leads to knowing, false-beliefs (Sally and Anne task), and hidden feelings.

Imprinting: Konrad Lorenz $1935$ observed innate attachment to the first moving object.
Evolutionary Theory: John Bowlby $1907-1990$ proposed monotropy and a critical period of $2.5$ up to $5\,\text{years}$ for attachment.
Harlow’s Monkeys: Harry Frederick Harlow $1905-1981$ found that social deprivation and the need for clinging (comfort) are more critical than nursing for normal development.
Attachment Styles: Mary Ainsworth $1913-1999$ developed the "Strange Situation" assessment.
Moral Development: Transitions from Moral Realism (judging by consequences) to Moral Relativism (judging by intentions) around $9-10\,\text{years}$

Teratogens: Agents disrupting embryo or fetus development.
Thalidomide disaster:
- Created in $1954$
- Licensed in UK in $1958$
- Link to birth defects published in $1961$
- Over $10,000\,\text{children}$ affected worldwide.

Are you a product of early experiences or continuing to change as an adult?
Can you change who you are?
Why is knowledge of development relevant for an allied health professional?
What aspects of development are most and least effectively modulated by education?
Do you believe in nature or nurture for development/health, and how does that affect AHP work?