Neurodevelopment is defined as the brain’s development of neurological pathways that influence performance or functioning. Environmental Enrichment (EE) is a form of neurodevelopment accessible to children with Down Syndrome at birth.

However, despite its beneficial effects it is not sufficient on its own to promote long term changes of the nervous system or significant developmental changes in children with Down Syndrome (DS) [1]. Discussed here, are adjuvant and alternative therapies which efficiently enhance neurological development in children with DS.

Neurodevelopment and Down Syndrome 

by Gabi Giacomin

It is well documented in research that the structure of the Down Syndrome brain is altered due to genes located on chromosome 21 which affect the brain’s ability to function properly. People with Down Syndrome experience difficulties with executive function, spatial learning and memory. This occurs because of alterations in brain structure, synapses and neurochemistry [2, 3]. A reduction in the number of dendrites (branches) and complex changes in the hippocampus affects proper functioning of synapses (ends of neurons which pass chemical and electrical signals to other neurons) [4]. In the DS brain there is also a disruption in the balance between excitatory and inhibitory neuronal systems [5]. This causes problems with neural plasticity which is essential for cognition (acquiring knowledge and learning through experience).

Environmental Enrichment

EE is a form of neurodevelopment based on holistic stimulation of the brain. It recognises all parts of the cerebrum are connected, and stimulation of one area of the brain stimulates other areas [6]. This is the reason reading is encouraged at a young age, as reading stimulates other cortical functions, including speech. Instead of using speech as the foundation for reading, reading is used to stimulate speech [6]. EE is based on a combination of stimulation using inanimate objects, social stimulation and exercise. Stimulation can be auditory, visual, tactile and social. EE promotes synaptic plasticity, the growth of neurons and epigenetic changes [8].

Exercise

Exercise stimulates neural plasticity. This enhances neuronal growth, learning and cognition seen in the hippocampus, cerebellum, cerebral cortex and throughout the brain [9]. Exercise improves academic achievement and intelligence in typical children and those with cognitive damage [10].

Providing your child with EE, partially improves these altered neurological characteristics [11]. However, if used in combination with phytonutrients, such as Green Tea, will promote long term changes of the nervous system and significant developmental changes in children with Down Syndrome (DS) [3].

Green tea

Recently, it was discovered that EGCg, a neuro-protective catechin found in Green Tea, significantly improved cognitive ability in people with DS and in mouse models [12]. It increased synaptic plasticity in vitro [13] and restored excitatory/ inhibitory imbalances in DS mouse models [14]. It inhibits DYRK1a [15] whose over expression leads to structural neurological and cognitive changes in DS [16].

Current research has found that the combination of EE and EGCg was very effective to recover neurophysiology and enhance cognition in youths with DS [12]. The combined treatment increased spinal density of dendrites (branches), normalised inhibitory and excitatory synapses and enhanced learning [17].

IAHP

Last year, 2016, details of a landmark pilot study were published analysing effectiveness of the IAHP’s neurodevelopment program for children with a focus on Down Syndrome (DS)[6]. The study accessed a database of 248 DS children who had undertaken the program over a period of 25 years [6].

While the IAHP program is considered to be a form of EE, it is unique. The IAHP recommend treatment before the age of five, unlike some therapies which wait until the onset of symptoms. Important components of the program include crawling on the floor, the progression of crawling to running at an early age, passive exercise for those not able to crawl (patterning), brachiating by moving across a monkey bar, early reading and maths, gymnastics and athletics, nutritional optimisation and avoidance of drugs that interfere with brain development [6]. Sensory stimulation may be auditory, visual, tactile or social [18] and promotes neurogenesis, learning, cognition and brain growth.

The positive effects of EE on brain development include changes in brain structure and enhanced activity of neurotransmitters and neurochemistry [8]. Improvements in problem solving, memory, learning and social interactions including improvement of brain injury, developmental delay and genetic alterations, as in DS [8].

Exercise has an extremely positive effect on the brain including the stimulation of neural plasticity leading to the growth of neurons, and improvements in learning and cognition [9]. Exercise improves academic achievement and intelligence in typical children as well as those with brain injury [10]. In combination with mental stimulation, exercise enhances the growth of neurons and improves neuron survival [19].

The rate of improvement using these techniques more than doubles brain growth. This is consistent with prior studies looking at adopted orphans and animals, despite the fact it seems extraordinary [6]. The potential for development for children with DS is greater than most people realise [6].

Conclusion

Overall, combined treatment of EE with EGCg simultaneously targeted several abnormal processes underlying intellectual disability in DS, and is considered optimal treatment as intervention to prevent disease in the DS population.

References

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