Table of Contents
1.1 Acquired Aphasia in Childhood
2.1 Aquired Aphasia in LKS
2.2 Abnormality in the Electroencephalogram
6 Comparison between LKS and Other Forms of Acquired Childhood Aphasia
8 List of Works Cited
“Aphasia is the neurological term for any language disorder that results from brain damage caused by disease or trauma.”1 The disorder is not exclusively found in adults, but may also occur in children. To lose the ability to understand and produce language may be a major catastrophe for children and has enormous consequences for their whole life, even if speech is regained after some time.2 Therefore, it is astonishing how little is known about the subject and how controversially it is discussed in literature. This paper introduces into acquired childhood aphasia with focus on a syndrome called Landau-Kleffner Syndrome, in which aphasia and epilepsy are combined. Landau-Kleffner Syndrome will be discussed in regard to symptoms, aetiology, therapy and prognosis. Moreover, it will be compared to other forms of acquired childhood aphasia.
1.1 Acquired Aphasia in Childhood
Speech disorders in children can be subdivided into two groups: developmental language disorders (for example stuttering) and aphasia. The former occur prior to language emergence and may have many different causes. The latter can be subdivided into congenital aphasia and acquired aphasia. Congenital aphasia is caused prenatal or perinatal whereas acquired aphasia always occurs postnatal.3 The focus of this paper will be on acquired aphasia in childhood. It is defined as the “deterioration in language performance as a result of cerebral affections.”4 Thus, acquired aphasia is the reduction or loss of language functions that have been acquired before. Therefore, language acquisition has to be (at least partially) completed. The linguistic symptoms can include all parts of language (that is phonology, morphology, semantics, syntax and lexicon). Both receptive and productive language skills can be affected and the child may not only have problems with spontaneous speech, but also with alphabetisating and repeating words and sentences. The constitution and severity of the different symptoms vary and depend on individual factors like the cause of the brain lesion.5 In children, the most common cause for acquired aphasia is a structural brain lesion arisen from traumatic head injuries (80%). Other reasons are infectious diseases (e.g. meningitis), intracerebral tumours and in some rare cases cerebrovascular accidents (which are very common in adult aphasia).6
For a long time it was believed that the prognosis for children with aphasia was good and that all children would recover language faculties; an assumption which had to be retracted. The prognosis depends on aetiology, the age of the child, the kind of aphasia and the degree and location of lesion, the latter one being the most important factor.7 Critchley distinguishes between focal or diffuse locations as well as static (e.g. embolism), regressive (e.g. trauma) and progressive (e.g. tumour) degrees of lesions. He proposes that focal, non-progressive lesions are rarely followed by permanent speech-defects. Therefore, the prognosis for such cases is comparatively good. Furthermore, he argues that the severest cases are diffuse and progressive lesions, which are mostly followed by permanent speech-defects.8 Consequently, a standard prognosis for all cases of aphasia cannot be taken, but Lenneberg points out, that the prognosis is better, the younger the child. If aphasia starts before puberty, the chance of recover is much better than afterwards.9
2 Landau-Kleffner Syndrome
In 1957, the neurologist William M. Landau and the pedagogue Frank R. Kleffner observed six children who all suffered from acquired aphasia and some kind of epilepsy and found a syndrome they called Syndrome of Acquired Aphasia with Convulsive Disorders in Children.10 Nowadays, the syndrome is mostly called Landau-Kleffner Syndrome (LKS). It is a rare disease (about 160 cases up to 1985)11 and in literature it is discussed controversially, thus, a clear definition cannot be taken.12 The aim of this paper, therefore, is to give an overview over LKS; minor deviations, which some researchers point out, are not taken into account.
Landau-Kleffner Syndrome occurs exclusively in children, the time of onset being between the age of two to thirteen. Nevertheless, adults may suffer from the consequences of the disease. Furthermore, boys are twice as often contracted by LKS as girls.13 The main symptoms of Landau-Kleffner Syndrome are acquired aphasia and an abnormal electroencephalogram (a further description of the two can be found in the following chapters).14 “A child who has been in good health with no neurological abnormalities or known brain pathology loses the ability to understand speech and to use it.”15 This inability may occur suddenly (75% of all children suffering from LKS) or gradually.16 Since there are no other neurological findings, there is often the suspicion of deafness at the beginning, but the child is not unable to hear, thus, the diagnosis has to be corrected.17 The child’s nonverbal intelligence is not impaired. Consequently, a discrepancy between verbal and nonverbal intellectual abilities is apparent.18 Moreover, the children often show behavioural disorders like aggressiveness, hyperactivity and attention deficits.19
2.1 Acquired Aphasia in LKS
Acquired aphasia in LKS can be subdivided into two groups. One group consists of those children who initially have got problems in understanding speech (receptive aphasia). Since 90 percent of all children suffering from LKS belong to this group20, research is concentrated on it and sometimes LKS is even reduced to this group. “The defect of language function is usually a verbal-auditory agnosia with an inability to comprehend language because of a defect in decoding phonologically.”21 A boy after having regained his linguistic ability explains that suddenly he could not understand what people said and everything just sounded like “blah, blah, blah”. The verbal-auditory agnosia is then followed by a rapid reduction of spontaneous speech and may result in a complete loss of it.22
The second group consists of those children, whose disorders are mainly in producing speech and who do not have problems with understanding it.23 This group did not get much attention in the past and further research has to be done in regard to the causes, prognosis and therapy.
2.2 Abnormality in the Electroencephalogram
Electroencephalography measures electrical activities of the brain.24 All children with LKS show an abnormal electroencephalogram (EEG). They have convulsions in both the left and the right hemisphere which are more frequent and more intensive during sleep.25 Epileptical seizure activities in the EGG (also called latent epilepsy) are shown by all children suffering from LKS. Furthermore, about 70 to 80 percent of the children suffering from LKS do not only show latent epilepsy, but show observable clinical seizures. Thus, children do not necessarily have to show clinical epilepsy, but it is very prevalent.26
There is an important discussion about the correlation between epilepsy and aphasia. Researchers argue about if both symptoms arise from independent causes or if they are consequences of the same cerebral dysfunction. There are mainly two hypotheses. The one claims that there is a direct connection between aphasia and epilepsy. Researchers found out that in some cases an improvement of the electrical seizure activity is followed by an improvement of aphasia. They conclude that aphasia is a consequence of epilepsy. However, others found the opposite. Even when abnormalities in the EEG completely disappear, speech-defects remain unimproved.27 Thus, they “propose that EEG abnormality in this syndrome is an epiphenomenon underlying pathology of brain areas concerned with speech rather than a cause of the speech abnormality.”28 The problem has not yet been solved; however, nowadays it is mainly assumed that the occurrence of electrical seizure activities during sleep affects the course of aphasia. Nevertheless, researchers suppose that the disappearance of seizures does not have an effect on the recovery of speech functions.29
1 Victoria Fromkin, Robert Rodman, and Nina Hyams, An Introduction to Language, 7th ed. (Boston: Thomson Heile, 2003) 37.
2 Neil Gordon, “Acquired Aphasia in Childhood: the Landau-Kleffner Syndrome,” Developmental Medicine and Child Neurology 32 (1990): 270.
3 Katharina Rupp, „Die erworbene Aphasie im Kindesalter: Eine katamnestische Untersuchung,“ MS thesis, Universität Bielefeld, 2006, 39-40, 20 July 2007 <http://www.aphasiker-kinder.de/plone/navigations/dpttree.2005-03-03.4975088807/dpttreeitem.2005-03-03.6533924892/dpttreeitem.2005-03-04.4534070440/dpt_html_view>.
4 Macdonald, Critchley, Aphasiology and Other Aspects ofLanguage (London: Arnold, 1970) 278.
5 Rupp 29-30.
6 Rupp 42-43.
7 Angelika Rother, “Kindliche Aphasien,” L.O.G.O.S. Interdisziplinär 2 (2005): 92, 20 July 2007 <http://www.aphasiker-kinder.de/plone/navigations/dpttree.2005-03-03.4975088807/dpttreeitem.2005-03-03.6533924892/dpttreeitem.2005-03-04.4534070440/dpt_html_view>.
8 Critchley 280.
9 Rother (2001) 55.
10 Angelika Rother, “Das Landau-Kleffner-Syndrom,“Aphasie und verwandte Gebiete 1 (2001): 19-27, 20 July 2007 <http://www.aphasiker-kinder.de/plone/navigations/dpttree.2005-03-03.4975088807/dpttreeitem.2005-03-03.6533924892/dpttreeitem.2005-03-04.4534070440/dpt_html_view>.
11 Gordon 270.
12 Angelika Rother, „Das Landau-Kleffner Syndrom,“ diploma thesis, Rheinisch- Westfälische Technische Hochschule Aachen, 1995, 10, 20 July 2007 <http://www.aphasiker kinder.de/plone/navigations/dpttree.2005-03-03.4975088807/dpttreeitem.2005-03-03.6533924892/dpttreeitem.2005-03-04.4534070440/dpt_html_view>.
13 Rother (1995) 10-11.
14 Rother (1995) 7.
15 Gordon 271.
16 Rother (1995) 58.
17 Gordon 271.
18 Rother (2001) 19-27.
19 Rother (1995) 23-24.
20 Rother (1995) 64-65.
21 Gordon 271.
22 Rother (1995) 64-65.
23 Rother (1995) 65.
24 “Electroencephalogram,” Encyclopaedia Britannica, CD-ROM, 3 discs (London: Encyclopaedia Britannica (UK), 2004).
25 Rother (1995) 14.
26 Rother (1995) 17-20.
27 Rother (1995) 21-22.
28 qtd. in Rother (1995) 22.
29 Rother (1995) 22.