Intelligence
ability to reason, understand, profit from experience
How do we measure intelligence?
-Intelligence Quotient (IQ)
- avg. is 100
- between 85 and 115 is normal
Intelligence tests are correlated with …
- pos with school and job performance, income, socioeconomic level
- neg with juvenile delinquency
Two Types of Intelligence
- fluid (Gf) and crystalized (Gc)
- proposed by Raymond Cattell
Fluid (Gf)
capacity to reason and solve novel problems, independent of any knowledge from the past
Crystallized (Gc)
ability to use skills, knowledge and experience
Lumpers
- intelligence is a single ability
- termed g for general factor
Splitters
intelligence is a collection of abilities that are more or less independent of one another
Einstein’s Brain
- slightly smaller
- relatively larger parietal lobes
- more glia in left parietal
General Intelligence is correlated with
- gray matter volume
- brain organization ( thicker cortex, smaller columns)
high IQ is related to neural efficacy…
- reduced energy (glucose) use
- faster transmission from short-term memory to long-term storage
Specific Abilities and their brain area
- Linguistic - left frontal, temporal areas
- Logical (mathematical) - left prefrontal cortex (rote calculation) ; parietal lobes (active calculation)
- Spatial - right parietal structures
Heritability of Intelligence
- 41% and increases with age
- high for brain volume
Genes related to Intelligence
- ASPM - brain size
- PACAP - neurogenesis
Intellectual Disability
- a limitation in intellectual functioning and in adaptive behavior originating before the age of 18
- IQ below 70 and difficulty meeting routine needs
How do we diagnose intellectual ability?
- conceptual : skills ( math, reading, language)
- social - empathy, communication, friendships
- practical - personal care, money management
Severity Levels
Mild - IQ 50-70 ; 85%
Moderate - IQ 35-49 ; 10%
Severe - IQ 20-34 ; 4%
Profound - IQ below 20 ; 1%
Trisomy 21 (Down Syndrome)
- genetic disorder caused by the presence of all (95%), or part of a third copy if chromosome 21
- leading genetic cause of intellectual disability
Translocational Down Syndrome
extra genetic material given from parents to baby
Fragile X Syndrome
- mutated FMRI gene, role in pruning excess synapses
- complete silence of gene results in avg IQ of 40
- co-occurs with autism and is a suspected genetic cause of autism
PKU ( Phenylketonuria)
- PAH gene mutation prevents enzyme that breaks down phenylalanine (amino acid)
- can lead to intellectual disability but can be prevented
Hydrocephalus
- fluid build up in ventricles, reducing brain tissue amount
- treated by using a shun
- 50% with 5% of brain capacity have IQs over 100
Autism Spectrum Disorder (ASD)
- set of neurodevelopment disorders characterized by social deficits, communication difficulties, and repetitive behaviors
- 1 in 68 children have ASD
Caused of ASD
Environment
- traffic pollution
- maternal metabolic conditions
Genetics
- Fragile X or Tuberous Sclerosis
Disorder of Brain Development
- brain grows rapidly after birth
-Lack of Amygdala and vmPFC coordination
-Decreased White matter
