2. Damage to
these areas
on the left
side of the
brain
usually
causes
language
disorder
(aphasia)
in adults
3. Specific language impairment (SLI)
is sometimes called
“developmental dysphasia”
or “developmental aphasia”
But the causes are different from
causes of adult acquired aphasia
4. Evidence against brain damage in
children with SLI: 1.
Children who do have brain injury affecting
the language areas don’t usually develop SLI
5. Extreme example of language development
after early damage to language areas
Brain scan after removal of
diseased cortex on left side of
brain to control epilepsy
Child without left-sided
language areas can still learn
to talk and understand!
Right side able to take over
language functions
6. Evidence against brain damage in
children with SLI: 2.
Brain scans don’t usually show evidence of
any injury, unless child also has other signs of
neurological damage
– E.g., epilepsy or motor (movement) problems
severe enough to indicate brain damage
7. Early study comparing children with SLI
with a typically-developing control group
Routine examination of MRI structural brain scans:
•No abnormality in 16/20 scans of language-impaired
•Slight abnormalities in the other four
•No abnormality in 8/12 typically-developing control children
•Slight abnormalities in the other four
Emphasises that we should not over-interpret slight abnormalities
– they are common!
Jernigan, T., Hesselink, J. R., Sowell, E., & Tallal, P. (1991). Cerebral structure on
magnetic resonance imaging in language- and learning-impaired children. Archives of
Neurology, 48, 539-545.
8. “There is now overwhelming evidence
that children with [specific] learning
disabilities do not have “holes in the
brain”. No ..studies have found a one-
to-one correlation between behavioural
symptoms and MRI or postmortem
pathology in [specific] learning
disabilities”C. Leonard, 1997, p 161
Because of UK/US differences in terminology, [specific] added for clarification
Leonard, C. M. (1997). Language and the prefrontal cortex. In N. Krasnegor, G. R. Lyon
& P. S. Goldman-Rakic (Eds.), Prefrontal cortex: Evolution, development, and behavioral
neuroscience (pp. 141-166). Baltimore: Paul H. Brookes.
9. Abnormal brain development in SLI?
Growing evidence that genes are important in
causing SLI
Genetic influence could affect early stages of
brain development
What would this look like?
– Brain may be atypical in shape/size?
– Connections between brain regions affected?
– Microscopic differences in brain cell arrangements?
Not many studies: still early days
10. Rare cases with malformations affecting
language areas: perisylvian polymicrogyria
Malformation evident from brain
scans
Typically associated with very
severe expressive language
difficulties and epilepsy
See blog by Rob Rummel-Hudson who
described the long pathway to getting a
diagnosis for his daughter, Schuyler
http://www.schuylersmonsterblog.com/
11. More commonly, only subtle evidence
of developmental abnormality on MRI
Frontal language
region (defined in blue)
very variable from
person to person:
Here looked at number
of ridges (gyri) and
fissures (sulci) in this
IFS: inferior frontal sulcus region
AAR: anterior ascending ramus
AHR: anterior horizontal ramus
PCS: precentral sulcus
Clark, M. M., & Plante, E. (1998). Morphology of the inferior frontal gyrus in
developmentally language-disordered adults. Brain and Language, 61, 288-303.
12. Clark & Plante study
Number of people with extra sulcus (either side)
1. Parents of language-impaired child
Parent with no language problems: 5/10 = 50%
Parent also has language problems: 20/30 = 67%
2. Parents of child without language problems
Parent has no language problems: 13/34 = 38%
Parent also has language problems: 6/8 = 75%
Conclusion: Greater chance of extra sulcus in those with language problems,
but association is far from perfect:
•Around 1/3 of adults with no language difficulties in self or child have extra
sulcus,
•Around 1/3 of adults with language difficulies in self AND child don’t have
extra sulcus
13. Subtle brain abnormalities associated with
rare gene mutation that cases SLI
Yellow:
Affected members of KE
family (N = 10) had LESS
grey matter than 10 age-
matched controls
Yellow:
Affected family members
had MORE grey matter
than controls
Watkins, K. E., (2002). MRI analysis of an inherited speech and language disorder:
structural brain abnormalities. Brain, 25, 465-478.
14. Study using structural and functional
scanning of children with SLI
• No gross differences seen in the brain
• Subtle differences in language areas in distribution of grey
matter – very similar pattern to KE family
• Also did functional brain imaging (fMRI). Can’t record brain
activation while speaking, because movements interfere
with the recording. But can look at activation of language
areas when doing a silent language task:
• Hear a word definition (e.g. “bees make it”) and must
think of the word
Badcock, N., Bishop, D., Hardiman, M., Barry, J. G., & Watkins, K. (2011). Co-
localisation of abnormal brain structure and function in Specific Language Impairment.
Brain and Language, 120(3), 310-320. doi: 10.1016/j.bandl.2011.10.006
15. fMRI: Activation to Silent Naming
Amount of brain
activation in silent
naming task for
typical children
(blue), brothers and
sisters of children
with SLI (green) and
children with SLI
(red).
SLI group shows
reduced activity in
language regions
Badcock, N., Bishop, D., Hardiman, M., Barry, J. G., & Watkins, K. (2011). Co-
localisation of abnormal brain structure and function in Specific Language Impairment.
Brain and Language, 120(3), 310-320. doi: 10.1016/j.bandl.2011.10.006
16. Cerebral lateralisation
Two sides of the
brain look similar,
but function
differently
In most people, the
left side is more
active during
language tasks
17. Study using functional transcranial Doppler ultrasound to
measure blood flow to left and right sides of brain while
thinking of words starting with a given letter
Adults with history of SLI or autism
Laterality index
L biased
R biased
typical ASD + low SLI SLI
N=11 language history current
N = 11 N= 9 N = 11
Whitehouse, A. J. O., & Bishop, D. V. M. (2008). Cerebral dominance for language
function in adults with specific language impairment or autism. Brain, 131, 3193-3200.
18. Study using functional transcranial Doppler ultrasound to
measure blood flow to left and right sides of brain while
thinking of words starting with a given letter
Adults with history of SLI or autism
People with
Laterality index
L biased language
difficulties tend
to be less
lateralised.
R biased
We don’t yet
know why this
typical ASD + low SLI SLI is so
N=11 language history current
N = 11 N= 9 N = 11
Whitehouse, A. J. O., & Bishop, D. V. M. (2008). Cerebral dominance for language
function in adults with specific language impairment or autism. Brain, 131, 3193-3200.
19. Overall…..
Most children with Specific Language Impairment
don’t have any evidence of brain damage
They may have slight differences in the size of
different brain regions, or in the balance of activity
on left and right sides
The differences are typically small and not seen in all
children with SLI
It’s not possible to diagnose SLI from a brain scan
Neurological investigations aren’t usually
recommended unless the child has very severe
language difficulties, physical impairments (motor
problems) or epilepsy
20. For further reading
see reference list on:
http://www.slideshare.net/RALLICampaign/sli-and-
the-brain