lec 7 Flashcards
What is intelligence?
Intelligence is the ability to reason, solve problems, understand ideas, and learn.
What is cognitive ability?
Cognitive ability refers to measurable processes like math ability, memory, and language.
What is the psychometric theory of intelligence?
Intelligence is a combination of measurable cognitive abilities, organized hierarchically and influenced by multiple traits.
What is the “g factor” in intelligence?
The g factor is the core feature of intelligence that influences performance on cognitive tasks but cannot be measured directly.
What is the heritability of intelligence?
Heritability of intelligence is about 0.5, meaning 50% of variance in intelligence is due to genetic factors.
What happens when maze-bright and maze-dull rats are raised in different environments?
No difference in impoverished environments
In enriched environments, maze-bright rats perform better, and maze-dull rats show improvement.
What is the role of NR1 knockout in intelligence studies?
NR1 knockout mice perform poorly on water maze tasks, indicating a role in learning and memory.
How does NMDA overexpression affect mice?
Transgenic mice with NMDA overexpression show better performance in water maze tasks and improved memory.
What is the role of BDNF in intelligence?
BDNF promotes neurogenesis, synaptic transmission, and synaptic plasticity (LTP and LTD).
How does the Val66Met polymorphism in BDNF affect memory?
It reduces hippocampal volume and impairs episodic memory due to inefficient intracellular trafficking of BDNF.
What is the function of COMT in intelligence?
COMT degrades dopamine at synapses; the Val158Met polymorphism is linked to increased working memory.
What was the breakthrough in educational attainment GWAS?
A large dataset (over 1 million people) showed that educational attainment is genetically correlated with IQ (r = 0.65).
What do genome-wide polygenic scores (GPS) predict about intelligence?
GPS predict about 10% of variance in intelligence by combining thousands of small genetic effects.
What gene is linked to novelty-seeking behavior?
DRD4 (dopamine receptor type 4).
How does the DRD4 VNTR polymorphism influence personality?
Long allele (6–8 repeats) is linked to higher novelty-seeking behavior.
What brain region is linked to sexual behavior in mice?
The medial preoptic area (MPOA).
How does lesioning the MPOA affect sexual behavior in male mice?
It reduces male sexual behaviors.
How is DRD4 linked to sexual behavior in humans?
VNTR polymorphism in exon III is linked to promiscuity and infidelity.
What defines an intellectual disability?
Onset before age 18, IQ below 70, and failure to reach developmental milestones.
What chromosomal abnormality causes Down syndrome?
Trisomy 21 (an extra copy of chromosome 21).
What chromosomal abnormality causes Edward syndrome?
Trisomy 18 (extra copy of chromosome 18).
What chromosomal abnormality causes Patau syndrome?
Trisomy 13 (extra copy of chromosome 13).
What genetic mechanism causes Fragile X syndrome?
Triple repeat expansion (CGG) in the FMRI1 gene on the X chromosome.
What gene is mutated in Rett syndrome?
MeCP2 gene on the X chromosome.
How is phenylketonuria (PKU) caused and treated?
Caused by a mutation in PAH; treated with a strict low-phenylalanine diet.
What is DiGeorge syndrome caused by?
Microdeletion on chromosome 22q11.
What genetic difference causes Prader-Willi and Angelman syndromes?
Loss of DNA segment on chromosome 15q11-13 (Prader = paternal, Angelman = maternal).
What gene is associated with dyslexia?
ROBO1 (polymorphism on chromosome 3p12).
ROBO1 study - 4 gens of 21 dyslexic people
