KNES 370 Lecture Notes - Lecture 21: Teratology, Groupon, Motor Skill
9 May 2018
School
Department
Course
Professor
Lecture 21
Developmental Variability and Developmental Delay
Since 1900, scientific advances have:
- Increased the life expectancy of human
o Average length on how long an individual can live
o Life span cannot change because determined by genes
The development of various skills may not be uniform
- The moutntain is actually a mountain range
- Can be a the skillful level for one skill and context specific at another
Kinds of Variablititly
- Intra-indiviudal variability
o Within a idiiudal’s perforae variablity
o Postural sway between you as a 4 year old and an adult
o Every trial is different
o If perfect, then will only see one line because will trace the same line over and
over again
o Younger child has larger variability than older peers and adults because
▪ Lower stability
▪ Variability is a good source for learning because they are exploring
environment
•
• Explotation form learning persepctive
• They can find better solution to do the movement—so wont be
good at something and will have more variability until they
become good
▪ Exploitationfollow a certain line that is not the optimal solution but
only solution you know
• Many adults do this
• Once they find the optimal solution, they follow
▪ Variability is a good thing so that they can find optimal solution
- Inter-individual variability
o Between idiiduals’ performance variability
o There is a range when that skill happens with different individual
▪ Sits without support
• Average age that this behavior shows with a child population and
bar means the range that the bar is
• The difference in the bar is inter-individual variability
find more resources at oneclass.com
find more resources at oneclass.com
Theoretical Persspective to Explain Cell Differentiation
- Waddington
o Everyone starts from same place, but when we develop with age and our paths
are different, the constraints and experiences explain
o ANSWER FOR VARIABLITY IS CONSTRAINT
- Why we start at same place and go different places:
o At birth—have billions of neurons, all the neurons will have have, everything is
possible
▪ Before birth—there are constraints which determine what we will be
later in life
o After birth
▪ Exubereant connecting between neurons—experiences build the
connections in brain
▪ Pruning of connections based on experience
▪ Strong evidence that experiences profoundly changes the brain
• New born
o Have much less dense connections than 2 years old
o Neural connections affect everything
• Visual development
o At birth—the number of synapses in the visual cortex =
2500
o 6 months later, they reach their maximm density of 18,000
synapses
▪ many more connection
o we all have same number at birth, but experiences make
them grow
• Deaf Infants
o If the are’t eposed t the laguage eiroet, the
they cant speak the language
• Mice in different environment
o Different environments, different motor mapping
o Dentrites are connected to other axles,
▪ One mouse in one environment have more
dentrites than mice in the other—more
connections
• Environmental Complexiity of Mice—Greenough and Colleagues
o Normal and enriched
o Trained mice in different conditions
▪ Motor skill learning—acrobats—obstacle course
requiring balance and coordination
▪ Walk rapidly group—o treadill (do’t eed to
think)
▪ Run on activity wheels—voluntary exercise (can
stop any time they want)
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Increased the life expectancy of human: average length on how long an individual can live, life span cannot change because determined by genes. The development of various skills may not be uniform. The moutntain is actually a mountain range. Can be a the skillful level for one skill and context specific at another. Intra-indiviudal variability: within a(cid:374) i(cid:374)dii(cid:448)udal"s perfor(cid:373)a(cid:374)(cid:272)e variablity, postural sway between you as a 4 year old and an adult, every trial is different. Waddington: everyone starts from same place, but when we develop with age and our paths are different, the constraints and experiences explain, answer for variablity is constraint. 2500: 6 months later, they reach their maximm density of 18,000 synapses, many more connection, we all have same number at birth, but experiences make them grow, deaf infants. Environmental constraints (imp for context specific and skillful: socioeconomic class, geographic location, country, family, peer group. Organism (reflexive, preadapted, and fmp, and sometimes context specific: biological/physiological, psychological.
