Lifespan Development Exam 1 (Weeks 3-5)

The five sensory contributors to cognition (in order)

1.   Touch (1st)

2. Proprioceptive/Vestibular

3. Smell/Taste

4.   Auditory

5.   Vision (Last)

Basic elements of cognitive development

• Visual attention (1-4 months)

• Spatial relationships (4-10 months)

• Cause and effect (10-12 months)

• Trial and error (12-18 months)

Basic elements of psychosocial development

• Diffuse attachments (0-6 months)

• Separation anxiety “attachment to primary caregiver” (6-12 months)

• Multiple attachments/affection (12-18 months)

• Expresses feelings (18-24 months)

• Concern for autonomy (2-3 years)

Basic elements of speech and language development

1. Babbling, cooing (0-6 months)

2. Single words (6-12 months)

3. 20-100 words (20-100 words)

Basic elements of oral motor development

• Suck, swallow, breathe priority (0-6 months)

• Against-gravity movement of body segments allowing for eating semi-solids, solids, and mouthing of toys (by 12 months)

• Sound production (by 12 months)

  1. suck swallow breath

  2. liquid ingestion

  3. active oral pattern expanded to vertical movements of the jaw and tongue

  4. controlled movement against gravity and coordinated

Basic elements of fine motor development

1. Eyes on a target (by 3 months) - first locates the target visually

2. Eye-head tracking (2-5 months) - the head joins the eyes on the target

Functional reach and grasp – what main systemic components are required?

ALL MUST BE PRESENT

• Visual fixation

• Anticipatory adaptation

• Proximal stability

• Manual capture and release

• Object manipulation

In-hand manipulation

Fast twitch fibers required → precise movement

Shift (hand manipulation)

Movment of an object on the surface OR among fingers

Rotation (hand manipulation)

Movment of an object around its axis

Translation/Penny test

Movement from finger → palm AND palm → finger

Describe the importance of play in develompment

Play is their exercise.

Play is more related to sensory-motor interaction (0-2 years)

Order of types of play by age (don’t need to know years?)

1. pretend by 2 years

2. role-play by 3 years

3. constructive play by 2 years,

4. Rule games by 6 years

5. complex rule games by 10 years.

3 Stages of play (infancy, one year, school)

1. Infancy: Repetitive gross motor activity without purpose

   • Improves control of motor patterns, provides stimulation for visual and auditory development, and increases strength and endurance

2. One-year: Exercise play (running, chasing)

3. School age: Rough and tumble, aids in socialization → aggression vs. play

Self-centered play

(year 1): Child is playing alone

Parallel play

(Year 2-4): Children play alongside each other but NOT with each other

Cooperative play

(Year 4-5): They play together, take turns, and influence each other

Social interaction of play (years)

• 5-7 years: observation of rules

• 7-12 years: circle of friends outside family

• 12-16: team sports, driven socially, intellectually, and artistically

Define the mechanostat theory and how it contributes to bone development

Mechanical input is used to develop effeicient load-bearing bones → bones adapt to the mechanical strain placed upon them by the pull of muscles or gravity in weight bearing positions.

Otherwise, osteoclast activity is favored = ↑ bone resorption due to lack of exposure to strain. This is how we develop osteopenia and osteoporosis

Newborn femur features

• The angle of inclination is GREATER than in the adults

• Weightbearing has a major role in ↑ congruency with the acetabulum

How does muscle contraction assist bone growth?

As muscle pulls on bone, it creates a traction force that increases density according to the mechanostat theory

Osteoporosis, how do we slow the process?

It becomes accelerated with:

• Reduced calcium intake (diet or due to medications that ↓ Ca+ reabsorption)

• Intestinal calcium absorption DECREASES with age

How to help?

• Require Vitamin D supplements to enhance Ca+ absorption

Describe joint changes in older adults (65 +)

• Joints become stiffer (↓flexible) due to losing synovial fluid (lubrication)

  • This can also be to to inactivity and aging structural changes

• Cartilage becomes thinner

• Decrease in elastic fibers

• Ligament and cartilage degeneration

Ages for growth spurs

• 1-4 years

• 10 years

How does PA impact length, size, curvature, and shape of bone?

• PA BEFORE puberty supports growth in bone and muscle mass

• HIgh impact activities → ↑bone growth (mechanostat theory)

• This sets up the individual for optimal bone function across the lifespan

LE + pelvic changes as infant begins to move

1. LEs + pelvis undergo angular, rotational and length changes

   1. These changes also occur in the tibia + ankle/foot complex. ER of the tibia increases from newborn → adult

   2. This relationship changes from genu varum → genu valgus by 3 years old

   3. Stabilizes by 7 years → then ↓ by 5 degrees

2. Femoral angle of inclination decreases = improved lever arm for ABDuctors

How does the spine and curvatures develop?

1. Cervical LORDOSIS present at birth (early ossification of the occipital bone)

   1. More evident by 3 months due to head control development

2. Lumbar LORDOSIS develops as the infant learns to sit ~8 months

When is skeletal maturity obtained?

epiphyseal plates close by age 25

Can bone lengthen after epiphyseal plate closure?

No, but it can still change in denisity

What factors contribute to IV disk changes in adults >30?

1. Nucleus pulposus loses ability to absorb water → becomes dehydrated → ↓ ability to work as a shock absorber

2. Nucleus fibrous becomes fibrotic? → disk flattened and less resilient

3. Incidence of back pain reported between 30-50

Osteopenia

Organic or inorganic components of bone fail to develop

Osteomalacia

Abnormal bone mineralization of matrix. Due to Ca+, vitamin D, or increased reabsorption. Bone chemistry is normal

Osteoporosis

Reduction in bone mass due to decreased formation or increased reabsorption, while bone chemistry is normal

• Contributing factors: Hormones, diet, ↓ and activity

  • H: ↓ estrogen = ↑ bone reabsportion

  • D: lack of vitamin D and calcium

Does bone grow faster than muscle, and if so, what are the implications?

Yes. Muscles can become tight, and if there is also a neurological or fibrous diagnosis, this can easily become contracture.

Type I Fibers

Slow twich, small, fatigue resistant. POSTURAL (SOLEUS)

Type II Fibers

Fast twitch, large, aerobic and anaerobic. FAST MOVEMENTS (GASTROC)

Does prenatal development of muscle fibers rely on motor neurons? Proteins?

They rely on proteins prenatally during the fetal period. We do get differentiation of fibers in weeks 31-37.

What is the best predictor of strength in adolescence?

Height

In both boys and girls, what hormone has the biggest influence in early puberty?

Testosterone

Explain the strength decline in adults and older adults in terms of isometric and concentric strength

• Decline in muscle strength starts at 50-70 years old (then rapid decline)

  1. Concentric strength decreases more

  2. Isometric strength decreased follows

• Eccentric strength is maintained better in older adults

What is sarcopenia? How can we avoid the effects of sarcopenia in older adults?

• loss of flesh” – Loss of muscle mass, quality, and strength seen during normal aging

• ↑ intramuscular and body fat levels

• Decline of strength in the muscle mass remaining is due to the decline in muscle quality

Need to help them stay active, nutritional counseling, and functional training (balance too).nutritional

What is apoptosis?

Programmed cell death that is inevitable with aging.

Does resistive exercise negatively impact growth and development in children?

NO

Are maximal weight lifts and competition-style weightlifting recommended in adolescents before skeletal maturity?

No. Need skeletal maturity first. (ACSM)

Is frailty in older adults a contraindication to exercise?

No but you need to know their tolerance and progress accrodingly

Can older adults still improve and regain function with training?

Yes

Before birth, circulation permits most of the oxygenated blood to bypass the liver and lungs via which three shunts?

1. Ductus venosus

2. Ductus arteriosus

3. Foramen ovale

These will close “neonate” (as soon as they are born)

What regulates the HR and contractiliy?

Originiates in the medulla → carried by the autonomic nervous system (ANS - PNS + SNS)

How do the sympathetic and parasympathetic systems affect HR and vasoconstriction/dilation?

• SNS: ↑HR and contractility (EPI and NE) / ↑ vasoconstriction

• PNS: ↓HR and contractility (Ach via vagus n.) / ↑ vasodilation

Where/what are the receptors that relay sensory information to the ANS and what is their role in BP regulation?

Baroreceptors and chemoreceptors relay sensory information through the NS. They detect changes in BP, oxygen and CO2 levels, and pH in blood.

1. Baroreceptors in aorta and cortid sinus (stretch)

2. Chemoreceptors in the aortic and carotid bodies

How do the SNS and PNS affect the pulmonary system?

• SNS: BronchoDILATION

  • Remember that you need your lungs “open” when you are running from a bear :)

• PNS: Bronchoconstriction

What coordinates the rythmic ventilatory cycle and mantain the depth of ventilation?

Brain stem centers (3 - PNS/SNS/Motor) in the medulla and pons

How is bloodflow regulated in the system?

By pressures exterted by various structures

Preload

Amount of pressure needed to stretch the ventricles during filling

Afterload

Amount of pressure needed to be exterted by the ventricles to overcome aortic pressure (open the valve → push blood out to the periphery)

Components of the conduction portion of the CP system

1. Bronchi - hyaline cartilage + smooth muscle

2. Bronchioles - smooth muscle + elastic fibers

3. PNS system input via vagus nerve - contraction of smooth muscle cells that changes the diameter (↓) of the bronchial tree

Components of the respiratory portion of the CP system

1. Branches of the bronchial tree

2. Alveolar ducts

3. Alveolar sacs

4. Alveoli

What is the difference between the conductive and respiratory bronchioles?

The respiratory bronchioles contrain alveoli along their walls

Where does gas exchange take place?

In the capillaries

What is surfactant? What produces it?

A detergent-like substance that mixes with water to decrease alveolar surface tension; allowing the alveoli to open more easily during respiration.

• Produced by Type II Epithelium

Without surfactant, what condition can occur?

Atelectasis- alveolar collapse

Identify the muscles involved in breathing - “Ventilatory pump”

Controls the flow of air, using:

• Diaphragm

• Rib cage musculature (intercostals, parasternals, scalenes, and SCM)

• Abdominal muscles

Why are chemoreceptors important? Where are they located?

Detect changes in the blood levels of oxygen and CO2, and pH of the blood, which → stimulates appropriate respiratory changes

• Located in the aortic and carotid bodies

Order of events with mechanics of ventilation

Inspiration:

1. intercostal muscles contract to elevate the rib cage

2. The diaphragm also contracts, increasing the diameter of the thoracic cavity

3. Together, the plural cavity expands and results in increased negative pressure in the thoracic cavity

4. Atmospheric air rushes in, and the lungs expand

5. This expansion activates stretch receptors, inhibiting inspiration

Exhalation:

1. Exhalation occurs passively with muscle relaxation and elastic recoil

2. Inhibitory input to inspiration is decreased, once again activating inspiration

When can a prenatal heartbeat be detected?

At 22 DAYS of gestation

In the prenatal time frame, what provides the baby with oxygen saturation of the blood?

Oxygen saturation of blood is from the umbilical circulation until birth when nearly all independent oxygen saturation occurs at birth within minutes.

When is surfactant first produced

At 20-22 weeks of gestation

What are the CV and Pulmonary adjustments made at birth?

1. Fluid inside the lungs is pushed out through the nose and mouth during labor. Remaining fluid is drained by the pulmonary vessels and the lymphatic system → The infant breathes spontaneously

2. Blood is shunted into the pulmonary circulation to recieve oxygen from the alveoli

3. Occlusion of the umbilical cord → ductus venosus (IVC) closes = decrease in pressure in IVC and RA

4. The foramen ovale and ductus arteriosus of the heart close

   • This marks the full transition into adult-like circulation

Can hypertension be a problem in both children and adults? And what are the health risks to hypertension?

Yes for both! Poor nutrition (high in sugar and fat), smoking.

Define paradoxical breathing

The belly protrudes with inhalation instead of the chest expanding (chest sinks instead).

NOT normal if:

• child is older than 306 months (when the rib cage and its musculature develop)

• can happen with disease, frail chest injuries, and paralysis of the cervical levels and T6-12.

At what age is the muscle developed in the walls of arteries found at alveoli?

At 19 years old

Age-related changes of the heart

• Hypertrophy of cardicac cells, but hypoplasia (↓#)

• Heart valves become stiffer (calcify)

• pacemaker heart cells in the SA node decrease

• pseudohypertrophy and thickening in the L ventricle

• HR decreases

• BP increases

• ↓ vascular compliance = ↑ resting BP

• Premature ventricular contractions (PVCs) are seen in older adults, due to changes in the conduction system

Describe the age related changes in vasculature

• Vessels are thicker, rigid, and dilated (↓efficiency)

• Thickening of the elastic arteries, fragmenting the fibers, leading to lipid infiltration and calcification

• This makes vasodilation and vasoconstriction more difficult

• Become more prone to orthostatic hypotension

T/F: Dilation of vessels occurs in distal vessels, while the proximal vessels show a thickening of the arterial wall with age

FALSE. Dilation occurs PROXIMALLY (in the aorta), then the arterial wall thickens in the PERIPHERAL vessels

Arteriosclerosis

Decrease arterial compliance due to age-related changes

Atherosclerosis

PATHOLOGICAL deposition of plaques in the inner layer of a blood vessel

• This can be prevented with regular aerobic and endurance exercise = ↓ CVD risk

Age-related losses (summary by Dr. Morgan)

• CO (Q) and oxygen uptake decrease with age

• Reduced baroreceptors activity

• Decreased adaptability of the CVS

• Decreased SNS responses to drops in BP (orthostatic hypotension risk)

• Decreased ability to ↑ heart rate

• Decreased contractility

• Decreased ability for vasodilation of the vessels in response to stress

T/F:While older adults are still trainable and can respond to the benefits of exercise, they need to continue to be consistent with exercise to lower BP over time truly

True

Decreased strength, ANS control, muscle enzyme levels, and the size of capillary networks all contribute to _________________

Functional losses

Age related changes to the pulmonary system

• Stiff bony thorax

• Osteoporosis and poor posture

• ↓ lung elasticity and compliance

• Insufficient respiratory musculature

• ↓ Alveolar surface area

• ↓ Pulmonary blood flow and volume