Motor Apraxia Research Articles

Teaching Object Permanence: An Action Research Study

Object permanence, also known as object concept in the field of visual impairment, is one of the most important early developmental milestones (Fazzi & Klein, 2002; Morss, 1984). The achievement of object permanence is associated with the onset of representational thought and language (Bruce & Zayyad, 2009; Wright, Lewis, & Collis, 2006). Object permanence is important to orientation, including the recognition of landmarks (Anthony, Bleier, Fazzi, Kish, & Pogrund, 2002). Independent mobility (such as crawling) improves visual attentiveness, which is critical to the achievement of later object permanence tasks (Bozeman& McCulley, 2010). Direct instruction can accelerate the mastery of object permanence in children with disabilities (Kahn, 1976; 1984; Morss, 1984; Rogers & Puchalski, 1988) and is more effective than general stimulation programs (Sloper, Glenn, & Cunningham, 1986). This article presents an action research study on teaching object permanence to a child with multiple disabilities and visual impairment. It illustrates some of the principles of assessment and instruction described in Bruce and Vargas (2012). The Institutional Review Board at Boston College approved this study, which was part of a set of action research studies on pivotal milestones that were conducted with children with multiple disabilities. THE PARTICIPANT Jamie, the participant in the study, was a 4-year old girl with severe, global developmental delays; a seizure disorder; and nonambulation (with no other independent means of mobility). Jamie had progressive myopia (with higher myopia in her right eye), staphyloma, and a tilted optic disc in her right eye; hypoplasia (in both eyes); nystagmus; and probable ocular motor apraxia. Although Jamie's visual acuity for stripes was measured at 20/94 with the best correction, this method underestimates visual responses to more complex and typical visual stimuli. Thus, her ophthalmologist determined that she was legally blind and referred her for registration with the state's Commission for the Blind. Jamie had poor visual attention; she struggled to make eye contact and to share joint visual attention on an object. Her visual attentiveness improved with prompts paired with pauses that allowed her time to direct her visual attention. Jamie had a history of sporadic ear infections and had tubes in her ears. Although later testing indicated that she had normal hearing, it is reasonable to suspect that she may have had a history of intermittent, mild hearing loss because of ear infections. However, she was consistently able to respond to verbal inputs during the study and was often observed to smile when provided with verbal praise. Jamie was also nonambulatory and displayed immature grasp patterns. RESULTS OF THE ASSESSMENT The action research team selected the following three assessment tools to determine Jamie's present level of performance on object permanence tasks: the Hawaii Early Profile (Parks, 2004); Assessment, Evaluation, and Programming System for Infants and Children, Second Edition, Volume 2, Test Birth to Three Years and Three to Six Years (Bricker et al., 2003); and Structured Informal Assessment of Object Permanence (Bruce & Vargas, 2012). The baseline assessment revealed that Jamie had achieved the following precursor behaviors to object permanence: She visually focused on a person or object (when prompting and pause were provided), visually followed an object moving in horizontal and vertical directions, and reacted to the disappearance of a slow-moving object or person (with a smile). She also exhibited the following early object permanence behaviors: She located a partially hidden object when concealment was observed and occasionally located a concealed object (when concealment was observed) and a constant auditory sound (emitting from the concealed object) was provided. Jamie was not able to locate a concealed object without sound cues or when concealment was not observed. …

Coexistence of protease sensitive and resistant prion protein in 129VV homozygous sporadic Creutzfeldt–Jakob disease: a case report

IntroductionThe coexistence of different molecular types of classical protease-resistant prion protein in the same individual have been described, however, the simultaneous finding of these with the recently described protease-sensitive variant or variably protease-sensitive prionopathy has, to the best of our knowledge, not yet been reported.Case presentationA 74-year-old Caucasian woman showed a sporadic Creutzfeldt–Jakob disease clinical phenotype with reactive depression, followed by cognitive impairment, akinetic-rigid Parkinsonism with pseudobulbar syndrome and gait impairment with motor apraxia, visuospatial disorientation, and evident frontal dysfunction features such as grasping, palmomental reflex and brisk perioral reflexes. She died at age 77.Neuropathological findings showed: spongiform change in the patient’s cerebral cortex, striatum, thalamus and molecular layer of the cerebellum with proteinase K-sensitive synaptic-like, dot-like or target-like prion protein deposition in the cortex, thalamus and striatum; proteinase K-resistant prion protein in the same regions; and elongated plaque-like proteinase K-resistant prion protein in the molecular layer of the cerebellum. Molecular analysis of prion protein after proteinase K digestion revealed decreased signal intensity in immunoblot, a ladder-like protein pattern, and a 71% reduction of PrPSc signal relative to non-digested material. Her cerebellum showed a 2A prion protein type largely resistant to proteinase K. Genotype of polymorphism at codon 129 was valine homozygous.ConclusionMolecular typing of prion protein along with clinical and neuropathological data revealed, to the best of our knowledge, the first case of the coexistence of different protease-sensitive prion proteins in the same patient in a rare case that did not fulfill the current clinical diagnostic criteria for either probable or possible sporadic Creutzfeldt–Jakob disease. This highlights the importance of molecular analyses of several brain regions in order to correctly diagnose rare and atypical prionopathies.

Clear as mud

Autism, childhood apraxia of speech and central auditory processing disorder are associated with significant disability. These conditions can be more difficult to diagnose. With significant controversy surrounding their definitions and most effective treatment options, understanding these conditions better may optimize outcomes. As earlier diagnosis and treatment become more commonplace, the type and intensity of intervention provided continue to be a topic of extensive interest and research. The protean nature of speech and language disorders requires careful consideration of several diagnostic causes. Problems with speech may reflect motor coordination or apraxia, problems with processing language may reflect an auditory processing disorder, whereas more profound delays may reflect cognitive disability or autism. Early consideration of different causes of delay will aid in the choice and application of appropriate therapies. Early identification and treatment of speech and language problems are known to result in better outcomes. By expanding one's differential diagnosis for speech and language disorders and understanding the link between early communication delay and later language learning, one hopes to mitigate the long-term effects these conditions have on children.

Genotype–phenotype correlations in early onset ataxia with ocular motor apraxia and hypoalbuminaemia

Early onset ataxia with ocular motor apraxia and hypoalbuminaemia/ataxia-oculomotor apraxia 1 is a recessively inherited ataxia caused by mutations in the aprataxin gene. We previously reported that patients with frameshift mutations exhibit a more severe phenotype than those with missense mutations. However, reports on genotype-phenotype correlation in early onset ataxia with ocular motor apraxia and hypoalbuminaemia are controversial. To clarify this issue, we studied 58 patients from 39 Japanese families, including 40 patients homozygous for c.689_690insT and nine patients homozygous or compound heterozygous for p.Pro206Leu or p.Val263Gly mutations who were compared with regard to clinical phenotype. We performed Kaplan-Meier analysis and log-rank tests for the ages of onset of gait disturbance and the inability to walk without assistance. The cumulative rate of gait disturbance was lower among patients with p.Pro206Leu or p.Val263Gly mutations than among those homozygous for the c.689_690insT mutation (P=0.001). The cumulative rate of inability to walk without assistance was higher in patients homozygous for the c.689_690insT mutation than in those with p.Pro206Leu or p.Val263Gly mutations (P=0.004). Using a Cox proportional hazards model, we found that the homozygous c.689_690insT mutation was associated with an increased risk for onset of gait disturbance (adjusted hazard ratio: 6.60) and for the inability to walk without assistance (adjusted hazard ratio: 2.99). All patients homozygous for the c.689_690insT mutation presented ocular motor apraxia at <15 years of age. Approximately half the patients homozygous for the c.689_690insT mutation developed cognitive impairment. In contrast, in the patients with p.Pro206Leu or p.Val263Gly mutations, only ∼50% of the patients exhibited ocular motor apraxia and they never developed cognitive impairment. The stepwise multivariate regression analysis using sex, age and the number of c.689_690insT alleles as independent variables revealed that the number of c.689_690insT alleles was independently and negatively correlated with median motor nerve conduction velocities, ulnar motor nerve conduction velocities and values of serum albumin. In the patient with c.[689_690insT]+[840delT], p.[Pro206Leu]+[Pro206Leu] and p.[Pro206Leu]+[Val263Gly] mutations, aprataxin proteins were not detected by an antibody to the N-terminus of aprataxin. Furthermore Pro206Leu and Val263Gly aprataxin proteins are unstable. However, the amount of the 689_690insT aprataxin messenger RNA was also decreased, resulting in more dramatic reduction in the amount of aprataxin protein from the c.689_690insT allele. In conclusion, patients with early onset ataxia with ocular motor apraxia and hypoalbuminaemia homozygous for the c.689_690insT mutation show a more severe phenotype than those with a p.Pro206Leu or p.Val263Gly mutation.

Disconnections in Infantile-Onset Saccade Initiation Delay: A Hypothesis

Infantile-onset saccade initiation delay (ISID), commonly known as congenital ocular motor apraxia, is characterized by difficulty in triggering horizontal volitional saccades. It typically presents with head thrusts in infancy and is often associated with developmental delay. Patients with ISID are reported to have abnormalities in various brain regions including the corpus callosum, brainstem, and cerebellum. We propose that ISID is caused by the disruption or disconnection of axons linking analogous brain regions involved in processing saccades across the two sides of the brain or bilateral damage to these regions.

An unusual cause of head drops

The presence of vertical ocular motor apraxia should prompt a careful assessment to detect an underlying neurometabolic condition. But congenital vertical ocular motor apraxia is a rare entity that may be attributed to perinatal stroke, hypoxia or kernicterus. We report a case of a 5-year old girl with congenital vertical ocular motor apraxia. Her magnetic resonance imaging (MRI) brain showed symmetrical high signal in the inferomedial thalamic nuclei in the distribution of the vessel of Percheron, a rare posterior cerebral artery variant. Awareness of this rare cause of childhood stroke may obviate unnecessary investigation.

MRI with fibre tracking in Cogan congenital oculomotor apraxia

Congenital ocular motor apraxia (COMA) occasionally shares with Joubert syndrome (JS) and related disorders (JSRDs) a peculiar malformation, the 'molar tooth sign' (MTS). In JSRDs, the absence of superior cerebellar peduncles (SCP) decussation is reported. To investigate whether COMA demonstrates similar abnormal axonal pathways. Eight healthy age-matched controls, three children with clinical COMA and one child with clinical JSRD underwent examination with a 1.5-T MRI scanner. Diffusion-weighted imaging (DWI), colour-coded fractional anisotropy maps and three-dimensional diffusion tensor imaging (DTI) tractography of the cerebellorubral network were analyzed. On DTI cartography, the 'red dot' originally supposed to represent the SCP decussation in the midbrain was present in controls as well in those with COMA but absent in the single case with JS. In none of the subjects including controls was 3-D FT able to depict the SCP decussation. When seeded, the red dot resulted in the ventral tegmental decussation (VTD). It was normal in controls and in patients with COMA but was absent in our single patient with JSRD. MTS was identified in alla patients with COMA and in the patient with JSRD. MTS can be present in both COMA and JSRD but the underlying anatomy depicted by fibre tracking is distinct. The main difference is the integrity of the VTD in COMA.

Rehabilitation for Apraxia

Graeme J. Hankey MD, FRCP Section Editor Limb or motor apraxia, which can occur after a stroke, is a disturbance of the conceptual ability to organize actions to achieve a goal. It can disrupt a person’s ability to perform everyday activities and to live independently but is not due to muscle weakness or sensory loss. This systematic review examined the effectiveness of cognitive rehabilitation aimed at apraxia after stroke. The primary outcome was at the level of disability (restricted activity), specifically whether any benefits were maintained beyond the end of the intervention. Short-term effects, impairment, mood, and quality-of-life measures were also investigated. A thorough literature search up …

OCULAR MOTOR AND LID APRAXIA AS INITIAL SYMPTOM OF ANTI-Ma1/Ma2-ASSOCIATED ENCEPHALITIS

Antibodies against Ma1/Ma2 antigens are typically associated with paraneoplastic neurologic disease. Most common are the involvement of the limbic and diencephalic system and the brainstem. We report a case of anti-Ma1 and anti-Ma2-positive encephalitis with predominant frontoparietal cortical involvement. The main initial clinical symptom was an ocular motor and lid apraxia. ### Case report. We report on a 49-year-old man who presented with blurred vision and drooping eyelids bilaterally. The symptoms had progressed over a period of 3 months. When we first saw the patient, he also had dysphagia and apathy. The patient was previously healthy and did not take any regular medication. Two weeks before the onset of symptoms, he had been vaccinated against tick-borne encephalitis. On examination of the ocular motor system, the patient had a downward deviation of the bulbi and an inability to elicit voluntary horizontal or vertical saccades and the optokinetic reflex. Reflexive saccades were preserved. Gaze holding, vergence, and smooth pursuit were impaired and vertical ocular motility was limited. The deficit could be overcome via the vestibulo-ocular reflex, indicating a supranuclear origin. …

日本神経学会２００８年度学会賞受賞者招待講演 脊髄小脳変性症の分子病態機序の解明

Recent advance of molecular biology reveals that quality control of intracellular environment takes an important role for maintaining the neuronal function. One is a quality control of protein and another is a quality control of nucleotide. Polyglutamine disease is a disease which caused by a failure of quality control of protein. Expanded polyglutamine repeats result in neurodegenerative disorders, but their cytotoxic structures remain to be elucidated. About the quality control of nucleotide in neuron, DNA single-strand breaks (SSBs) were continually produced by endogenous reactive oxygen species or exogenous genotoxic agents. These damaged ends posses damaged 3'-ends including 3'-phosphate, 3'-phosphoglycolate, or 3'-alpha, beta-unsaturated aldehyde ends, and should be restored to 3'-hydroxyl ends for subsequent repair processes. We have demonstrated by in vitro assay that aprataxin, the causative gene product for early-onset ataxia with ocular motor apraxia and hypoalbuminemia/ ataxia with oculomotor apraxia type 1 (EAOH/AOA1), specifically removes 3'-phosphoglycolate and 3'-phosphate ends at DNA 3'-ends, but not 3'-alpha, beta-unsaturated aldehyde ends. The findings indicate that aprataxin removes blocking molecules from 3'-ends, and that the accumulation of unrepaired SSBs with damaged 3'-ends underlies the pathogenesis of EAOH/AOA1. The findings will provide new insight into the mechanism underlying degeneration and DNA repair in neurons.

Prominent Oromandibular Dystonia and Pharyngeal Telangiectasia in Atypical Ataxia Telangiectasia

Ataxia telangiectasia (A-T) typically presents with early-onset progressive cerebellar ataxia, oculomotor apraxia and later, oculo-cutaneous telangiectasia. Extrapyramidal symptoms, apart from chorea, are rare. In this paper, we report a case of A-T with an atypically mild and slowly progressive disease course. Although by history there was mild gait clumsiness in early childhood, the leading problem was that of dystonia with onset at age 15, in the absence of gross gait imbalance or ocular motor apraxia. Dystonia was generalized and with prominent oromandibular involvement. Unusually, a leash of telangiectasia was present on the posterior pharyngeal wall, while other features frequently associated with A-T were absent.

Misleading behavioural phenotype with adenylosuccinate lyase deficiency

Adenylosuccinate lyase deficiency is a rare autosomal disorder of de novo purine synthesis, which results in the accumulation of succinylpurines in body fluids. Patients with adenylosuccinate lyase deficiency show a variable combination of mental retardation, epilepsy and autistic features and are usually discovered during screens for unexplained encephalopathy using the Bratton-Marshall assay that reveals the excretion of the succinylaminoimidazolecarboxamide riboside (SAICAr). Here, we report on two sisters aged 11 and 12 years presented with global developmental delay, motor apraxia, severe speech deficits, seizures and behavioural features, which combined excessive laughter, a very happy disposition, hyperactivity, a short attention span, the mouthing of objects, tantrums and stereotyped movements that gave a behavioural profile mimicking Angelman syndrome. Both patients had an increased succinyladenosine/SAICAr ratio of 1.6, and exhibited a novel homozygous missense mutation (c.674T>C; p.Met225Thr) in the exon 6 of the ADSL gene. We suggest that these clinical features might be a new presentation of adenylosuccinate lyase deficiency. On the basis of this observation, although adenylosuccinate lyase deficiency is a rare disorder, this diagnosis should be considered in patients with mental retardation and a behavioural profile suggestive of Angelman syndrome.

Magnetic Source Imaging of Cortical Dysfunction in Amyotrophic Lateral Sclerosis

The goal was to determine whether magnetic source imaging could identify a signature for cortical involvement in patients with amyotrophic lateral sclerosis (ALS), and to determine whether the method might provide insight into functional abnormalities associated with the disease process. Spontaneous brain activity recordings from whole-head 148-channel magnetoencephalography (MEG) were employed to look for localized dipolar sources of focal delta-theta (1-7 Hz) discharges in patients with ALS without dementia. Localized slow wave dipoles were mapped and counted by anatomic brain region, defined by MRI, and correlated against the revised ALS functional rating scale (a functional measure of ALS disability). In a substudy, defects in cortical activations mediating purposeful movement were investigated in an ALS patient with probable motor apraxia of an upper limb. MEG revealed localized slow wave dipole sources in 7/7 ALS patients, including two recently diagnosed patients (0/8 age-similar controls). Systematic brain mapping of dipole source generators was possible in all seven ALS patients. The slow wave bursts were being generated from frontal, temporal, and parietal cortices, but not from occipital areas. The density of slow wave dipoles in cingulate gyrus correlated with the severity of upper-extremity disability as judged by the functional ALS measure. Further magnetic source imaging in the substudy patient with unilateral limb apraxia revealed abnormal central processing of purposeful movement with absent M2 in the contralateral secondary motor areas generating slow waves. This exploratory study documents widespread cortical dysfunction in patients with ALS, including those with recent onset of their disease. MEG is likely to be a powerful new tool for researching the contribution of cortical dysfunction to the motor disability that characterizes the disease process.

Congenital Ocular Motor Apraxia

Congenital ocular motor apraxia is a rare disease characterized by defective or absent voluntary and optically induced horizontal saccadic movements. Jerky head movements or thrusts on attempted lateral gaze are a compensatory sign. Most affected children have delayed motor and speech development. Cases associated with systemic diseases, neurologic maldevelopment, metabolic deficits, and chromosomal abnormalities have been described. Case report and review of the scientific literature. The authors describe the ophthalmologic, pediatric, and neurologic evaluations and follow up of a child with impaired horizontal saccades, jerky head movements, and delayed motor and speech development. Congenital ocular motor apraxia is an uncommon disorder of ocular motility. Even so, ophthalmologists should be aware of the developmental delay and the other associated conditions, in order to grant the patients the multidisciplinary assistance they often require.

Phenotype variability in progranulin mutation carriers: a clinical, neuropsychological, imaging and genetic study

Frontotemporal dementia (FTD), characterized by behavioural and language disorders, is a clinically, genetically and pathologically heterogeneous group of diseases. The most recently identified of the four known genes is GRN, associated with 17q-linked FTD with ubiquitin-immunoreactive inclusions. GRN was analysed in 502 probands with frontal variant FTD (fvFTD), FTD with motoneuron disease (FTD-MND), primary progressive aphasia (PPA) and corticobasal degeneration syndrome (CBDS). We studied the clinical, neuropsychological and brain perfusion characteristics of mutation carriers. Eighteen mutations, seven novel were found in 24 families including 32 symptomatic mutation carriers. No copy number variation was found. The phenotypes associated with GRN mutations vary greatly: 20/32 (63%) carriers had fvFTD, the other (12/32, 37%) had clinical diagnoses of PPA, CBDS, Lewy body dementia or Alzheimer's disease. Parkinsonism developed in 13/32 (41%), visual hallucinations in 8/32 (25%) and motor apraxia in 5/21 (24%). Constructional disorders were present in 10/21 (48%). Episodic memory disorders were frequent (16/18, 89%), consistent with hippocampal amnestic syndrome in 5/18 (28%). Hypoperfusion was observed in the hippocampus, parietal lobe and posterior cingulate gyrus, as well as the frontotemporal cortices. The frequency of mutations according to phenotype was 5.7% (20/352) in fvFTD, 17.9% (19/106) in familial forms, 4.4% in PPA (3/68), 3.3% in CBDS (1/30). Hallucinations, apraxia and amnestic syndrome may help differentiate GRN mutation carriers from others FTD patients. Variable phenotypes and neuropsychological profiles, as well as brain perfusion profiles associated with GRN mutations may reflect different patterns of neurodegeneration. Since all the mutations cause a progranulin haploinsufficiency, additional factors probably explain the variable clinical presentation of the disease.

Interventions for motor apraxia following stroke

Apraxia is a cognitive disorder that can occur after stroke. It prevents a person from carrying out a learned movement. Various interventions are used to treat apraxia but evidence of their benefit has been lacking. To determine which therapeutic interventions targeted at motor apraxia reduce disability. We searched the Cochrane Stroke Group Trials Register (last searched November 2006). In addition, we searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2006), MEDLINE (1966 to November 2007), EMBASE (1980 to November 2006), CINAHL (1982 to November 2006), PsycINFO (1974 to November 2006), the Research Index of the Occupational Therapy Journal (searched November 2006), REHABDATA (1956 to November 2006), the National Research Register (searched November 2006) and Current Controlled Trials Register (searched November 2006). We reviewed the reference lists of all articles that we identified as relevant. We made efforts to find both published and unpublished trials by writing to key authors and journals. Randomised controlled trials of therapeutic intervention for motor apraxia in stroke. One review author searched the titles, abstracts and keywords. Four review authors extracted data and analysed trial quality. We contacted investigators for further details of trials if necessary. Three trials including a total of 132 participants were included in the review. There was evidence of a small and short-lived therapeutic effect in the two studies that reported change in activities of daily living (102 participants) but this was not considered clinically significant and did not persist at the longer-term follow up. There is insufficient evidence to support or refute the effectiveness of specific therapeutic interventions for motor apraxia after stroke. Further research of higher quality is required. As we did not review whether patients with apraxia benefit from rehabilitation input in general, they should continue to receive general stroke rehabilitation services.

Myopathy in Gaucher disease

Gaucher disease is a recessively inherited lysosomal storage disorder, caused by deficiency of glucocerebrosidase activity. Affected individuals usually present with hepatosplenomegaly, anaemia, thrombocytopenia, and skeletal diseases. A wide range of neurological manifestations have also been recognized in Gaucher patients including acute neurological deterioration in infancy, mental retardation, ocular motor apraxia, seizure, and parkinsonism. Although muscle weakness is not an uncommon finding in patients with Gaucher disease, the aetiology of weakness is not well understood. We prospectively investigated seven Gaucher patients and found that four of them (patients 1-4) had mild to moderate degree of proximal-predominant symmetrical muscle weakness in four limbs. By history, three patients (patients 1-3) developed insidious onset of nonprogressive muscle weakness in four limbs with easy muscle fatigue from adolescence. A needle electromyographic study detected some small, brief polyphasic waves in these four patients. Muscle biopsy in one patient (patient 1) showed a few atrophic type II muscle fibres without infiltration of Gaucher cells. Three patients (patients 1-3) continuously received enzyme replacement therapy with imiglucerase and their muscle strength seemed improved after two years. We concluded that Gaucher disease may be associated with myopathy.

Posterior reversible encephalopathy syndrome in SLE nephritis

A 16-year-old girl with systemic lupus erythematosus (SLE) nephritis was started on pulse methylprednisolone and monthly cyclophosphamide infusion. She was already on antihypertensive for border line hypertension (130/80–140/90 mm Hg)....

The natural history of Unverricht‐Lundborg disease: A report of eight genetically proven cases

We report eight cases of genetically proven ULD, with the aim of reassessing the clinical characteristics and natural history of ULD in genetically characterized patients. The eight patients had their first symptoms at mean age of 10.6 years (range: 6-14 years). The main clinical features were action myoclonus, cerebellar ataxia, seizures, and mild intellectual dysfunction. We report three new clinical features of ULD; ocular motor apraxia, dystonia, and rapidly progressive dementia. All patients needed a combination of at least four antimyoclonic drugs, but despite this, all patients were severely disabled by their action myoclonus. After a mean duration of disease of 29.9 years (range: 21-37 years), four patients were walking with aids while another four were wheelchair bound. The clinical phenotypes associated with ULD are more diverse than previously recognized and even though the long term functional outcome and survival have improved, the overall efficacy of antimyoclonic drugs remains unsatisfactory.

Purkinje Cell Loss in the Cerebellar Flocculus in Patients with Ataxia with Ocular Motor Apraxia Type 1/Early-Onset Ataxia with Ocular Motor Apraxia and Hypoalbuminemia

We genetically screened patients with ataxia with ocular motor apraxia type 1 (AOA1)/early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH), with a Japanese variant form of Friedreich’s ataxia. Three patients were found to have a homozygous insertion mutation of the aprataxin gene (689insT). An elder sister of a patient in this series died of cerebral hemorrhage at the age of 45, and underwent autopsy. In her cerebellar cortex, the mean density of Purkinje cells in the flocculus had predominantly decreased to 6.7% of normal controls, whereas the Purkinje cells in the other areas of the cerebellar hemisphere had decreased to 78.2%. This suggests that the cerebellar flocculus is the primary affected lesion in AOA1/EAOH, which should be associated with ocular motor apraxia.