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Advanced Neurology Improving cognitive development in Down syndrome

that it is possible to augment the span capacity by several Specific craniofacial dysmorphia is responsible for
units, especially in young children, by training overt a good part of these difficulties. They involve: cranial
cumulative rehearsal and phonological processing. doming, shortening of the skull along the anteroposterior
axis, midfacial hypoplasia with maxillary deficiency,
Regarding LTM, the evidence suggests that explicit
memory abilities are more impaired in individuals with DS flattened nose bridge, insufficient lip seal, high palate with
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reduction in length, and narrowed oropharynx. These
than implicit ones, which appear to be more independent anomalies determine masticating, swallowing, and often
from cognitive level. The correct functioning of explicit breathing difficulties with sleep apnea. Sleep disturbance
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memory depends on the integrity of the medial temporal may interfere with slow brain waves during NREM sleep
lobe, in particular the hippocampal and peri hippocampal and fragilize synaptic consolidation in LTM, further
structures, in relationship with the prefrontal cortex, the hindering cognitive development. Dental malocclusion
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caudate nucleus, and the anterior cingulate cortex. 38,39 with maxillary transverse discrepancy and posterior
Volumetric and magnetic resonance imaging studies of crossbite is frequently observed. 47
individual with DS reveal a disproportionately smaller
volume of the frontal, temporal, and cerebellar regions. 40 At least four dosage-sensitive genes determine the
craniofacial phenotype in Dp1Tyb mice that recapitulates
Implicit memory involves the frontal, parietal, and key aspects of the human DS craniofacial dysmorphology.
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superior temporal cortices of the left brain, the left-basal One of them is DYRK1A whose overexpression results in a
ganglia (most importantly the striatum with the caudate decreased proliferation of neural crest cells and a decrease
nucleus and the putamen), and the right-neocerebellar in the size of frontal bone primordia. This causes defective
structures. Research in brain hemodynamics, skull bones with aberrant mineralization of the growth
electrophysiology, and magnetoencephalography has plates between cranial base bones. EGCG molecules
documented differences between the two kinds of attach to the adenosine triphosphate binding site of a
memories at the neuronal and molecular level. 41 DYRK1A protein altering its function. As indicated, doses
A key aspect in episodic memory is the degree of of 30mg/kg/day of EGCG administered to Ts65Dn mice
organization of the material to be recorded. At the coding improve the facial skeleton of the animals. Complicating
stage, the relevant characteristics of the information need the dosage matter is the fact that a similar dose chronically
to be related to each other in relevant ways, which helps administered from embryonic time in these mice reduces
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retrieving them from LTM. The hippocampal cortex mineral density in longer bones.
codifies entering information for computing an index of Analyses of the phonological processes highlight
the contents of the LTM store. close similarities between children with DS and those
with typical development. This means that the strategies
Memory intervention at this level is directed
toward increasing the subjects consciousness regarding developed for helping typical children with articulatory
delays can be used with DS children.
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organizational characteristics of the material to be
remembered. 42 Specific programs for boosting lexical acquisitions in
children with DS have been tested and found efficient.
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5.2. Language intervention Early vocabulary training is all the more important as the
Twenty years of functional imagery have yielded a precise first words are usually quite delayed in children with DS,
picture of the relationship between particular brain areas which contributes to slowing down the whole language
and language functions. The brain of persons with DS is development. Joining manual signed expressions (for
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characterized by an underdevelopment of the frontal and example, borrowing from the lexicon of the American sign
temporal lobes hosting two of the major language areas, language of the deaf) with oral productions can help the
that is, the Broca area (Brodmann areas 44, 45, and 47) child to progress more rapidly in the early stages of lexical
on the production side of language functioning and the development. Fast mapping of novel objects names and the
Wernicke area (Brodmann areas 22, 41, and 42) on the acquisition of internal state vocabulary (words referring to
reception one. 44,45 sensory perception, positive and negative effects, affective
behaviors, moral judgments, and volition) can then
Language intervention in DS centers on the major proceed toward building extended lexical networks. Here
components of the language system, that is, speech, also, the typical patterns of development in non-retarded
lexicon, and morphosyntax. children are found in children with DS. 51

As said, speech development is retarded in individuals Morphosyntactic training concentrates on promoting
with DS and is often incomplete. the understanding and expression of the major semantic

Volume 4 Issue 1 (2025) 5 doi: 10.36922/an.3785