Psychology

Dyslexia

There are very many learning disabilities but dyslexia is the leading disability (Voeller, 2004). This condition has weighed down so many children who have sufficient intellectual ability in addition to learning opportunities and willingness. It is a devastating hereditary disorder that renders children incapable of enjoying the experience of smooth reading and phonological expression. The condition is more common in boys that in girls based on different developmental factors (Habib, 2000). As such, it is important to know how these differences come about and the way it presents in girls. Its correct early diagnosis can be very useful in meeting the needs of a child whether educational or social.

This work is a discussion on dyslexia seeking to identify the developmental reasons behind its higher prevalence in boys than in girls. On the same note, the work will touch on how and when dyslexia is diagnosed. Since prevalence is high in boys than in girls, this work will discuss on the signs whose presence shows that a girl may be dyslexic. The work will also explore on the current protocols available to make sure that dyslexic girls get their needs in education and other fields of life.

What is dyslexia
According to Ramus (2004, p 2), developmental dyslexia is a mild hereditary neurological disorder which manifests itself as a persistent difficult in learning to read in children with otherwise normal intellectual functioning and educational opportunities. As per this definition, it is clear that developmental dyslexia does not only entail having neurobiological dysfunctions but it is also passed along the genetic line. A broad range of difficulties are experienced in dyslexics and this is why dyslexia has a neurological perspective, cognitive as well as behavioral aspect. It is estimated that 5-17 percent of the population is affected by this disorder.

How does developmental dyslexia present
It is first important to realize that dyslexia is more common in males than in females although this has not been universally agreed. Differences in prevalence depend on a particular study but it has been shown to be in the ratio between 2 females 3 males and 4 5 (Habib, 2000).  Children suffering from developmental dyslexia may be affected in several domains (1) dysphasia where deficits occur in acquisition of oral language (2) dysgraphia as well as misspelling where the child has writing difficulties (3) dyscalculia where mathematical abilities are impaired (4) dyspraxia characterized by deficits in motor coordination (5) dyschronia which is a deficit in maintaining a stable posture and temporal orientation and (6) attention deficit disorder and hyperactivity.

Signs and symptoms of dyslexia
Dyslexia is characterized by a wide spectrum of signs and symptoms. Although reading difficulties are usually mentioned as paramount, Ramus (2003 in Ramus, 2004), says that there are also problems with phonology (the mental representation and processing of speech sounds), sensory difficulties in the visual, auditory and tactile domains, problems with balance and motor control among other difficulties. Along with these symptoms is also the likelihood of comorbidity with such disorders as specific language impairment and attention deficit hyperactivity disorder among others.

Trying to look at the neurobiological basis of dyslexia can provide important information on what underlies dyslexia. Studies on individuals who are normal against dyslexic individuals show that the posterior left hemisphere of dyslexics is less active. In addition, the anterior and the posterior of the left hemisphere have low synchrony as compared to normal readers (Voeller, 2004). It is therefore evident that phonological problems are the most dominant in dyslexics rather than visual problems.

The classroom (especially in the kindergarten level) is the most likely place to identify initial signs that eventually indicate dyslexia upon further examination. Nevertheless, it can also be identified before school age (Ingesson, 2007). Phonemes particularly become tough for dyslexic children to attend to. A child who is having difficulties in writing numbers as well as letters such that these are commonly reversed may be showing signs of dyslexia. A child may for instance write 9 when they actually meant 6 or write q as p and vice versa (Orton, 1925). This problem should be persistent over a period of time since children at the age of 7 years usually have this difficulty which ceases with time. A potentially dyslexic child however shows persistent difficulties in reversing letters and numbers.

As a result of difficulties with phonemes and reading abilities, a child suffering from dyslexia will tend to be socially withdrawn probably out of the fear of ridicule. Social conflicts and strains arise among the peers and low self esteem takes up the life of a dyslexic child (Ingesson, 2007, p  580). Ingesson says that among the dyslexic students that they interviewed regarding their self esteem, 40 percent felt that the dyslexia had influenced their self-esteem negatively quite a lot or very much. This is expected since the child is likely to feel stupid and slow when they compare with fellow students.

Diagnosing dyslexia
For children who have not entered school, it is likely to see signs such as talking at a late age, the child may be slow in acquiring new words or still face difficulties in rhyming.  These should be warning signs that the child will most likely develop dyslexia. Upon persistence of the above signs and symptoms, a parent should be moved to seek professional help for diagnosis of the condition. It is possible to predict dyslexia in a child even at infant stage during the first year of life. The processing of speech sound in such infants tends to vary from those without the risk of dyslexia. By the second year of life, it is possible to identify minor deficiencies in the language of the child. The risk of dyslexia is relatively high in children aged two yeas and below if there is simultaneous diagnosis of delayed language as well as motor skills. As the age of the child increases, it becomes easier to identify a dyslexic child. Catts (1991, in Voeller, (2004, p 742) acknowledges that by age 5 years, weak letter-sound knowledge, naming, and phonemic awareness are apparent.

There are many standardized tests available for diagnosing dyslexia. Among them include the Kaufman Tests of Educational Achievement, Welchsler Intelligence Scale for Children, Motor-Free Visual Perception Test, Test for Auditory Comprehension of Language, Woodcock-Johnson Psycho-Educational Battery and Peabody Individual Achievement Tests-Revised among others. The tests are then matched against the childs intelligence quotient.

It is pertinent to note that early and correct diagnosis of dyslexia depends primarily on the ability of a parent (or caregiver) to identify warning signs at an early age. The teachers are also very important in leading to accurate diagnosis of dyslexia. Whenever these two parties notice the lead signs and symptoms, a professional in dyslexia should then be brought in to carry out the necessary diagnostic tests.

Why is dyslexia more prevalent in boys than in girls
As mentioned earlier, developmental dyslexia is found to be more prevalent in boys than in girls although it lessens with age.  There are genetic links associated with this type of dyslexia. The fact that a person is form a family having a dyslexic individual doe not imply that one must end up becoming dyslexic.  It is important to state that environmental factors such as lack of exposure to reading and writing at a tender age tend to aggravate phonological and reading problems. Combining this aspect with genetic predisposition makes one more prone to dyslexia.

The neurological basis on developmental dyslexia suggests that the brain of the affected child particularly in the left hemisphere is affected such that the language centers are poorly developed leading to the language and speech difficulties seen in dyslexia. The higher prevalence of dyslexia in males as compared to females however is weakly linked to hormonal factors and specifically the sex hormones. It is important to note that the notion of high prevalence of dyslexia in males that in females prevailed in the 1980s where it was suggested that males are four times more likely to have dyslexia than females in the Western world. This view is however changing with an establishment that prevalence is almost equal across both genders. In actual sense, these differences are seen due to differences in study criteria.

Disorders in the development of the brain and particularly the left hemisphere are at the center of dyslexia. Due to existence of differences in hemispheric specialization in males and females, it is thought that this may contribute to differences in prevalence of dyslexia in males and females. For males, verbal processing is strongly specialized in the left hemisphere with the right hemisphere having strong specialization for spatial processing. Females on the other side do not have strict specialization in verbal or spatial processing on either side of the brain and instead they portray a bihemispheric specialization. As a result of this hemispheric specialization, females will tend to show a higher verbal ability than males but a lower spatial ability. In addition, if boys would get injured in the left hemisphere, it often becomes hard for them to have the right hemisphere take up the role of verbal processing. This inability to switch specialization across the hemisphere has big consequences if any of the hemispheres is inefficient. The implication of these hemispheric specialization differences imply that if the boys experienced malformations in the left hemisphere, they are mainly going to derail in their verbal processing ability unlike girls who can easily switch these functions to the opposite hemisphere.

Studies have been carried out to try and explain the phenomenon of cerebral lateralization as explained above. Individuals with dyslexia have unusual symmetry in the planum temporale of the cerebral hemispheres. Planum temporale is mainly larger in the left hemisphere and its main role is to process audio information and language. The phonological problems associated with dyslexia are therefore likely to be found in people with an abnormal planum temporale which is a significant part of the left hemisphere of which males specialize in processing audio information (Voeller, 2004).

The difference in specialization of the left hemisphere and the ability to switch tasks across the hemisphere is further cited to be a major difference in prevalence of dyslexia among males and females. The fact the left hemisphere is specialized in auditory processing in males as compared to bihemispheric specialization in females further pushes boys into the corner of having more cases of dyslexia. Post-mortem studies have shown that brain cells are kind of misplaced in the cortex (a phenomenon called ectopia) and generally disordered deviant from their regular arrangement in the cerebral cortex. Since these cells are responsible for processing language and are largely found in the left hemisphere, ectopias in this region imply that this function is interfered with. Again boys suffer most because of lack of bihemispheric specialization which is found in females.  Studies on dyslexic women show that these women tend to activate right hemisphere structures to a great extent. The implication here is that women are able to switch roles into the right hemisphere whenever the left hemisphere is dysfunctional. Eventually, dyslexic consequences may not be severe with girls as with boys.

Hormonal factors have been cited to influence development of dyslexia. Fetal testosterone in particular has been mentioned to play a part in development of dyslexia and this happens during late pregnancy. The hormone factor goes hand in hand with the role and collasum and its development. In particular, the mid-posterior section of the callosum has direct proportionality with the levels of testosterone in the saliva. Since the callosum is involved in interhemispheric connections and its development is determined by fetal testosterone, the levels of fetal testosterone determine this interconnection by influencing the size of the posterior part of the callosum. According to a study carried out by Duara and colleagues on the role of posterior callosum in dyslexia, they found out that the size of the callosum was larger in females than in males who had dyslexia and that the posterior part of the callosum was larger in both males and females who had dyslexia as compared to controls who were non-dyslexic. It can therefore be concluded that a large posterior callosum interferes with interhemispheric communication leading to dyslexia. Since the size of the callosum is a factor of fetal testosterone, high fetal testosterone in males than in females during embryonic stages leads to a large callosum and subsequently incompetent communication between cerebral hemispheres and consequently higher incidences of dyslexia in males.

Low verbal ability in a girl child should sound bells for the likelihood of dyslexia. This is because girls are generally known to have higher verbal ability due to their bihemispheric specialization ability. Dysfunction in both sides of the hemisphere or the communication thereof will therefore interrupt the strong verbal ability and the girl may be concluded to have dyslexia.

Ensuring that dyslexic girls get the most out of life
It is important to stress that dyslexia is not a disease but rather it is a condition. Dyslexics are also both lazy and unmotivated individuals of low intelligence capacity. In fact dyslexics are almost always above average in intelligence. For this reason, dyslexics can get the most out of life and their lives are not entirely limited by difficulties in reading. Dyslexic children are usually among the most creative individuals as far as art work is concerned. Since dyslexic girls are mainly incompetent in their verbal skills, several protocols have been proposed to help meet their needs.

There are several remediation programs developed to help dyslexic children improve in their phonetics and reading difficulties experienced by dyslexics. Temple et al (2003, p 2860) say that the remediation program is computer-based and it helps dyslexics train in oral language, including auditory attention, discrimination, and memory, as well as phonological processing and listening comprehension. From these trainings, dyslexics have been shown to greatly improve in reading as the rather inactive left hemisphere becomes activated significantly. The activation of the brain hemispheres is of major significance in improving phonological processing bearing in mind that dyslexia is more of a neurological condition. Putting dyslexic girls in such remediation programs go a long way in restoring their hope of effective reading.

Other than just working towards restoring the phonological abilities in dyslexic girls, it is of value to consider encouraging the dyslexic girls to participate more in areas that they can excel most. This would help them overcome low-self esteem associated with dyslexic children. Ingesson (2007, p 588) suggests that dyslexic children should be encouraged in areas such as sports, social activities or a special interest where they can do well and which makes them view themselves positively. Offering special education to dyslexic at an early age can help them safeguard their self-image whereas the parental and professional support comes in handy in dealing with poor self image in dyslexics.

Conclusion
The above discussion on dyslexia is a strong indicator that this condition is more of a developmental condition that is ruining the lives of many children who are not empowered with information that it can be successfully dealt with. Difficulties in reading as with dyslexia are not to mean that the child is a failure in life. This is because the child still has enough intelligence and can actually excel in other areas such as art and activities requiring physical coordination.

It has been identified that dyslexia is more likely to be in boys than in girls due to developmental disorders of the brain. Cerebral lateralization is the center of all this and therefore ability to have bihemispheric coordination in females gives girls an advantage of escaping dyslexia. Males however are disadvantaged by their left hemisphere specialization that is responsible for speech and language processing. A problem in the hemisphere either due to injury or developmental anomalies is likely to result to dyslexia. Recognizing the specific difficulty a dyslexic child is having is the biggest step towards correcting the problem and ensuring that the child gets the most out of life. Remedial programs and emotional support from parents and professionals is also important for meaningful living.