8. Nature and Nurture of Language Development Flashcards
Language ability appears in the first ____ years of life, across different l____ and c____
Three
Languages, cultures
We have an ____ ability for language ability
innate
We can gain language ability without the need of e____ instructions
Explicit
Early language skills are very important to children’s c____
Chances
The most widely used test by all speech pathologists is the C____ E____ of L____ F____:
Child’s understanding and u____ of language and compares this to their p____ of the same a____
Clinical Evaluation of Language Fundamentals
use, peers, age
Nature = ____ factors
Nurture = ____ factors
Genetic
Environmental
What are three forms of evidence for the role of nature and nurture?
1. T____ studies
2. The KE family with members with l____ d____
3. G____ a____ studies
- Twin studies
- The KE family with members with language disability
- Genetic association studies
We can compare resemblance of MZ and DZ twins on a specific tr____ by looking at co____
Trait
Correlations
In twin studies, what do the following stand for??
1. A
2. C
3. E
- Heritability (proportion of variance in a population attributable to genetic differences between people)
- Common environment (degree to which siblings in a family are similar to one another, once their genetic similarity has been accounted for)
- Unique environment (degree to which siblings in a family are different from one another, once their genetic differences have been accounted for)
In twin studies of language ability, at age 2 heritability for vocab is ____%, ____% for grammar in boys and ____% for grammar in girls
26, 52, 43
What are five limitations of twin studies of language ability?
1. Large sa____ si____ required
2. Po____-based samples preferred, to avoid ov____ of MZ pairs
3. Difficult to id____ twins
4. Language ph____ are li____ and lacking in me____ interpretable for comparisons to si____ age peers
5. Possible tw____ effect
- Large sample sizes required
- Population-based samples preferred, to avoid overrepresentation of MZ pairs
- Difficult to identify twins
- Language phenotypes are limited and lacking in metrics interpretable for comparisons to singleton age peers
- Possible twinning effect (twins more likely to have delayed speech and language skills than singletons)
Behavioural phenotype: for every test of s____ and l____ that was administered, the group of affected family members was significantly i____ relative to the u____ group
speech, language
impaired relative to the unaffected group
Neural phenotype: Bilateral voxel-based morphometry analyses shows some of the regions in which affected KE family members have sig____ red____ gr____ ma____
significantly reduced grey matter
FOXP2 gene is the gene that is responsible for the s____ and l____ d____ in the KE family
the speech and language disorder in the KE family
A single mutation in the KE family leads to a loss of f____ of one copy of the FOXP2 gene, and the one copy that remains is i____ for normal brain d____, leading to the speech and language disorder
function, insufficient, development
Define monogenetic trait
Cause by a m____ in a s____ g____
Cause by a mutation in a single gene
A comparison of the FOXP2 gene of humans, other primates and other placental mammals shows that FOXP2 is among the most highly conserved 5% of pr____, indicating it has a fu____ role in mammals
proteins, fundamental
Genetic influences are not ____ - heritability language ability ____ during development
static
increases
Multiple genetic factors of language development have been identified, suggesting language ability is a m____ trait
Multifactorial trait
Genetic and environmental factors do not act in ____, but ____ to influence child language development
Isolation, co-act
How do you calculate heritability?
Heritability = 2(rMZ - rDZ)