DEVELOPMENTAL PSYCHOLOGY By: Hayley Whitlock & Emily Ehmann

Prenatal Development ➢ The germinal stage: The germinal stage begins with conception, when the sperm and egg cell unite in one of the two fallopian tubes. The fertilized egg, known as a zygote, then moves toward the uterus. This can take up to a week to complete. Cell division begins about 24 to 36 hours after conception. ➢ The embryonic stage : The mass of cells is now know as and embryo. The embryonic stage begins after implantation and continues until cell differentiation has been mostly completed. Structures important to the support of the embryo develop, including the placenta and umbilical cord. During this time, cells begin to differentiate into the various body systems. The basic outlines of the organ, body, and nervous systems are established. By the end of the embryonic stage, the beginnings of features such as fingers, eyes, mouth, and ears become visible. ➢ The fetal stage: Once cell differentiation is mostly complete, the embryo enters the next stage and becomes known as a fetus. The early body systems and structures established in the embryonic stage continue to develop. The neural tube develops into the brain and spinal cord and neurons form. Sex organs begin to appear during the third month of gestation. The fetus continues to grow in both weight and length, although the majority of the physical growth occurs in the later stages of pregnancy.

Developmental Changes Physical changes: As people get older, hair begins to thin out and become gray, weight tends to increase, number of neurons decline in the brain. As children get older, their height grows, and in late adulthood height slightly decreases. Muscle strength and reaction speed reaches its peak in the early to mid-20's.

– Cognitive changes: Birth to 2: responses to stimulus, babbling represents spoken language, and the first word is usually used around age : Thought is marked by concentration and short term memory capacity increases : Children begin to be able to focus on more than one feature of a problem and long term memory improves : Thoughts become more abstract and the thought of “what could be” comes into existence : Information processing speed is stable, greater emphasis on application, and more contradictions of pros and cons : Increasing wisdom, long term memory begins to decline, and speed of learning and problem solving begin to decline. 65 and older: Individual experiences gradually decline, decisions making becomes more cautious, and fluid intelligent decreases.

– Social changes: Temperament is developed by ages 2-4 months. Attachments to care givers is established around 6-8 months. Stranger anxiety is established around 6-7 months and separation anxiety shows around months. At ages 2-4 years, children begin to learn gender roles and the social world is extended beyond family; friendships are formed. During Middle Childhood, ages 6- 12, children begin to understand others feelings and same sex relationships are formed. At ages 12-20, dating begins and interactions with the opposite sex develop. During ages 20-40, Energies are focused on intimate relationships, raising a family, and managing a home. At ages 40-65, increased attention of mortality beings to occur as well as shifting of energy between career concerns to family needs. When a person reaches age 65 or older marital satisfaction increases, but eventually death of spouse results in coping challenges.

Attachments and their Effects on Children Attachment theory has led to a new understanding of child development. Children develop different styles of attachment based on experiences and interactions with their caregivers. Four different attachment styles or patterns have been identified in children: secure, anxious-ambivalent, anxious- avoidant, and disorganized. Attachment theory has become the dominant theory used today in the study of infant and toddler behavior and in the fields of infant mental health, treatment of children, and related fields. Secure attachment: A toddler who is securely attached to its parent (or other familiar caregiver) will explore freely while the parent is present, typically engages with strangers, is often visibly upset when the parent departs, and is generally happy to see the parent return. The extent of exploration and of distress are affected by the child's temperamental make-up and by situational factors as well as by attachment status, however. Therefore, secure attachment can be seen as the most adaptive attachment style. According to some psychological researchers, a child becomes securely attached when the parent is available and able to meet the needs of the child in a responsive and appropriate manner. Others have pointed out that there are also other determents of the child's attachment, and that behavior of the parent may in turn be influenced by the child's behavior. Disorganized attachment: A frightened caregiver is alarming to the child, who uses social referencing techniques such as checking the adult's facial expression to ascertain whether a situation is safe. A frightening caregiver is usually so via aggressive behaviors towards the child (either mild or direct physical/sexual behaviors) and puts the child in a dilemma which Main and colleagues have called 'fear without solution.' In other words, the caregiver is both the source of the child's alarm as well as the child's haven of safety. Through parental behaviors that are frightening, the caregiver puts the child in an irresolvable paradox of approach-avoidance.

Childhood Developments Attachment emerges out of a complex interaction between infant and mother. Mothers who are sensitive and responsive to their child's needs tend to evoke a more secure attachments than mothers who are insensitive and inconsistent in their responding. Studies show that there is a relationship between secure attachments and more advanced cognitive development during childhood and adolescence. Babies who receive non maternal care for more than 20 hours per week have an increased risk of developing insecure attachments to their mothers. Evidence suggests that day care is not harmful to children's attachment relationships. Day care can have benefits on some children's social development.