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It has now been 100 years since Hugo Liepmann, in his classic 1920 paper described limb kinetic, ideomotor, and ideational apraxia. There are now several rating scales used to assess and grade the signs and symptoms associated with Parkinson’s disease; however, none of these assesses patients for the presence of these disabling forms of upper limb apraxia. This paper, reviews the four types of apraxia that can be associated with Parkinson’s disease, how they can be tested, the disabilities associated with these disorders and possible treatments.

Apraxia is a disorder of the skilled movements that are needed successfully perform transitive or intransitive movements, when this disorder is not caused by failures of comprehension, weakness, sensory loss, or involuntary movements. The following forms of upper limb apraxia have been reported to be associated with Parkinson's disease: (1) limb-kinetic apraxia, a loss of the ability to make precise, independent but coordinated finger-hand movements; (2) ideomotor apraxia, a failure to make the correct joint movements, to coordinate these movements with the correct timing, speed, and force; and (3) ideational apraxia, the incorrect sequencing of a series of actions required to complete a goal. This chapter summarizes the means of testing for these different forms of apraxia, the types of errors made by patients with these forms of apraxia, and the pathophysiology and treatment of these disorders.

A previous exposition of apraxia in Practical Neurology 1 offered an account of underlying impairment and accompanying clinical assessment based on a distinction between ideational, ideomotor and limb-kinetic apraxia. This conceptualisation stems from 19th-century models of higher cortical motor, language and visual function, revived by Geschwind2 3 in the 1960s. Liepmann in 19004 had posited a hierarchical model of action control over three discrete levels. At the top, movement formulae (‘visual engrams’ of the action) provided overall targets, which activate innervatory patterns to stimulate the appropriate muscles, coordinated contraction of muscles then led to execution of the action. (1) Ideational apraxia arose when movement formulae were either impaired or disconnected from the innervatory patterns. (2) Ideomotor apraxia resulted from disruption to innervatory patterns. (3) Limb-kinetic apraxia , assumed to be a disruption to the smooth neural transmission of the motor commands, was, even for Liepmann, not a full apraxia. It existed between apraxia and paresis only within a broader view of dysfunction. Liepmann’s model proved valuable in studying apraxia. However, despite surviving in several neurology textbooks, the ideational–ideomotor dichotomy has now been replaced as a way of understanding and classifying apraxias,5–8 similar to the disbandment of Broca’s versus Wernicke’s aphasia, or the dichotomy of associative versus apperceptive agnosia9 (although these distinctions, too, still persist in some areas of clinical practice). A radical rethink was needed, owing to issues with the underlying theoretical model of apraxia and difficulties in distinguishing between ideational and ideomotor clinically. Goldenberg7 made the plea to ‘relegate the dichotomy of ideational …

We describe an autopsy case of basophilic inclusion body disease (BIBD), a subtype of frontotemporal lobar degeneration (FTLD) with the appearance of fused in sarcoma (FUS) inclusions (FTLD-FUS), clinically presenting corticobasal syndrome (CBS). A 54-year-old man initially developed worsening of stuttering and right hand clumsiness. Neurological examinations revealed rigidity in the right upper and lower extremities, buccofacial apraxia, and right-side dominant limb-kinetic and ideomotor apraxia. Neuroimaging showed asymmetric left-dominant brain atrophy and a cerebral blood flow reduction in the ipsilateral frontal region. At 56 years, his apraxia had advanced, and ideational apraxia was observed. Furthermore, the asymmetry in the limb-kinetic and ideomotor apraxia had disappeared, and both conditions had become bilateral. He had a new onset of aphasia. His symptoms progressed and he died 9 years after the initial symptoms. The brain weighed 955 g. Diffuse brain atrophy was most obvious in the bilateral frontotemporal regions. The atrophy of the left superior frontal and precentral gyri and bilateral basal ganglia was remarkable. Histologically, there was a marked loss of neurons with gliosis in the affected areas, where basophilic neuronal cytoplasmic inclusions were observed. The inclusions were immunoreactive for FUS, p62, and TATA-binding protein-associated factor 15 (TAF15), but not for phosphorylated tau, transactive response DNA-binding protein of 43 kDa (TDP-43), neurofilament protein, or Ewing sarcoma (EWS). From these pathological findings, this case was diagnosed as having BIBD as an FTLD-FUS variant. Spinal cord lower motor neurons were spared in number, similar to primary lateral sclerosis. Mutations in FUS were undetectable. Common background pathologies for CBS include corticobasal degeneration, Alzheimer's disease, PSP, FTLD with phosphorylated TDP-43 inclusions (FTLD-TDP), Pick's disease, Lewy body disease and CJD. However, FTLD-FUS (BIBD) has been rarely reported. Our case suggested further pathological heterogeneity in CBS than had previously been reported. It is necessary to consider FTLD-FUS (BIBD) as a background pathology for CBS in the future.

It is not unusual to observe hemichorea in patients with diabetes mellitus, with origins attributable to recent ischemia. Our patient was a 66-year-old female with diabetes mellitus who suddenly developed right hemichorea, mild muscle weakness of the right upper extremity, ideational apraxia, and acalculia. Her blood glucose was 600 mg/dL, and HbA1c was 13.3%. After the patient underwent head magnetic resonance imaging (MRI), a new cerebral infarction was observed in the left frontal lobe, and treatment was started with edaravone and cilostazol. At the same time, insulin treatment was also started for hyperglycemia. The acalculia and ideational apraxia improved approximately 1 week after treatment initiated, and the hemichorea also decreased. ECD-SPECT was performed on admission, and it was observed that blood flow was decreased in the left frontal lobe and striatum, but increased in the thalamus; two weeks later on follow-up ECD-SPECT, blood flow had increased slightly in the left forebrain and striatum, while it had decreased slightly in the thalamus. This suggests that the cause of hemichorea was related to ischemia. When the activity of the pallidum is impaired, it is presumed that the inhibitory activity towards the thalamus weakens and the thalamic cells become over-excited, causing chorea.

Aside from being measured in the context of producing facial expressions of emotion, the ability to voluntarily control a range of facial muscles in Parkinson's disease (PD) has not been systematically measured. We used in three enrollment phases an adaptation of the Upper and Lower Face Apraxia test, a measure of the ability to make voluntary movements of the upper and lower face in PD patients and healthy controls. Errors were scored due to (1) pauses prior to movement initiation, (2) loss of individuation, (3) impoverished movement, (4) no movement at all, or (5) content errors (likened to ideational apraxia errors). The results show impaired voluntary control of facial musculature in most but not all with PD (with large effect sizes) which correlated positively and highly with disease severity. Errors by PD patients were predominantly due to impoverished movement and individuation loss whereas those made by controls were predominantly due to individuation loss. Patients committed more errors than controls due to impoverishment and no movement, with negligible differences between groups in other errors. In summary, similarly to spontaneous and voluntary emotional expressions, voluntary non-emotional facial movements are impoverished in PD; impoverishment of all movement types will likely contribute to the mask-like facial appearance that is seen with disease progression. These findings also illustrate the utility of an adapted Face Apraxia test as a practical and sensitive measure of voluntary facial musculature control in PD. The test can be used to supplement clinical observations and as a research tool.

We present a case of callosal disconnection syndrome as a rare manifestation of acute disseminated encephalomyelitis (ADEM). A dextral 48-year-old Japanese woman received trivalent inactivated influenza vaccine in mid-November 2011. Twenty days later, she was found to be in a daze. Subsequently, she developed abnormal behavior and gait disturbance, and she was disoriented regarding time and place. Nystagmus and abnormal ocular movements were absent. Upper limb power was normal, whereas her lower limbs were mildly weak. Tendon reflexes were normally evoked without pathological reflexes. There was no sensory impairment. Serum CRP levels were slightly elevated; other routine laboratory tests, thyroid functions, and vitamin B1 levels were within the normal range. Cerebrospinal fluid examination revealed that it was acellular with a protein level of 54 mg/dl and high myelin basic protein level. Fluid-attenuated inversion recovery MR images revealed a large hyperintense lesion in the corpus callosum, but the lower part of the splenium was spared. Flow voids were observed in the pericallosal arteries. She was diagnosed with post-vaccination ADEM and vigorously treated with an intravenous infusion of methylprednisolone (1 g/day for 6 days) and immunoglobulin (1.2 g/kg). Gait disturbance and disorientation rapidly improved; however, tactile anomia, ideomotor apraxia, ideational apraxia, and agraphia of the left hand were present one month after onset. She had no aphasia or alexia.Interestingly, the patient's left unilateral agraphia was more prominent in kana than kanji (an article in Japanese text) for polysyllabic words, whereas she could write kana characters to dictation. Changes in the sequential order of kana characters within a word were observed. These findings were similar to those observed in pure agraphia associated with lesions in the posterior part of the left middle frontal gyrus. Thus, an interhemispheric mechanism is probably involved in the selection and arrangement of kana characters to form words.

Neuropsychological studies showed that manipulatory and semantic knowledge can be independently impaired in patients with upper-limb apraxia, leading to different tool use disorders. The present study aimed to dissociate the brain regions involved in judging the hand configuration or the context associated to tool use. We focussed on the left supramarginalis gyrus (SMG) and left middle temporal gyrus (MTG), whose activation, as evidenced by functional magnetic resonance imaging (fMRI) studies, suggests that they may play a critical role in tool use. The distinctive location of SMG in the dorsal visual stream led us to postulate that this parietal region could play a role in processing incoming information about tools to shape hand posture. In contrast, we hypothesized that MTG, because of its interconnections with several cortical areas involved in semantic memory, could contribute to retrieving semantic information necessary to create a contextual representation of tool use. To test these hypotheses, we used neuronavigated transcranial magnetic stimulation (TMS) to interfere transiently with the function of either left SMG or left MTG in healthy participants performing judgement tasks about either hand configuration or context of tool use. We found that SMG virtual lesions impaired hand configuration but not contextual judgements, whereas MTG lesions selectively interfered with judgements about the context of tool use while leaving hand configuration judgements unaffected. This double dissociation demonstrates that the ability to infer a context of use or a hand posture from tool perception relies on distinct processes, performed in the temporal and parietal regions. The present findings suggest that tool use disorders caused by SMG lesions will be characterized by difficulties in selecting the appropriate hand posture for tool use, whereas MTG lesions will yield difficulties in using tools in the appropriate context.

To successfully interact with the environment, goal-oriented movements made by human limbs must be guided by instructions from the brain. Loss of the ability to program purposeful skilled movements, in the absence of any motor, sensory, or cognitive deficit that could fully account for this disability, is called apraxia. Several types of apraxia were described by Hugo Liepmann in the beginning of the 20th century: ideomotor apraxia, where patients make spatial movement and postural errors as well as temporal errors, limb-kinetic apraxia, where patients are unable to perform precise independend and coordinated finger movements and ideational apraxia, where patients fail to correctly sequence a series of action. More recently, three other types of apraxia have been described: conceptual apraxia, where patients have a loss of mechanical knowledge; dissociation apraxia, where patients are impaired at performing a skilled act in response to stimuli in one modality but can perform normally when the stimulus is given in another modality; and conduction apraxia, where patients are impaired at action imitation. This chapter, using an historical approach, reviews the signs associated with each of these forms of apraxia, as well as their pathophysiology.

We report data from a group of patients with mild Alzheimer's disease on a range of tasks requiring either stored semantic knowledge about objects (e.g., naming object use) or the execution of action to objects (e.g., miming and using objects). We found that the patients were impaired at miming in response to objects, even when they could describe the object's function. On the other hand, copying gestures was not impaired relative to naming gestures, indicating that an ideomotor deficit in action execution, per se, was unlikely to explain the impairments in object use. We suggest instead that the patients had an impairment in stored motor programmes for action, over and above their deficits in semantic knowledge. Despite this, the patients were better at using than at miming to objects, consistent with the view that proprioceptive input (when using objects) can directly constrain selection of the appropriate motor programme for action.

Neurologists are familiar with the standard definition of apraxia: ‘an inability to perform a motor task that cannot be adequately explained by motor weakness, sensory loss or a lack of understanding’. Being a definition of exclusion, this has led to a bewildering number of motor disorders being described as forms of apraxia, despite many of these failing to capture the essence of what apraxia really is: a disorder of motor cognition. Apraxia reflects an impairment of the storage and transformation of motor representations in the brain, either through degradation of the semantic knowledge of gestures and tool use or through inability to translate the neural representations of higher level goals accurately into lower level patterns of muscle activation and inhibition. Our current clinical approach to apraxia is similar to that proposed by Liepman in the early 20th century.1 He recognised that left hemispheric lesions tend to cause bilateral upper limb apraxia and suggested a model of motor control in which the left parietal lobe stores a ‘space–time form picture’ of a movement. For a movement to be executed, its picture must be retrieved and activated and then be associated via cortical projections with the relevant motor engrams in the prefrontal regions. From here the information passes to the primary motor cortex before being fed down the corticospinal tracts. For the right upper limb to move the information remains contained within the left hemisphere, but for the left upper limb to move the information from the left parietal lobe must first be sent to the right prefrontal and frontal regions through the corpus callosum. Using this scheme, Liepman delineated three forms of apraxia. He described ideational apraxia as a disruption of the space–time picture, in which the idea of the movement itself is lost or degraded. In ideomotor apraxia , …

A large left hemisphere porencephalic cyst was incidentally found in a 48-year-old woman (MS) with a Diagnostic and Statistical Manual (DSM)-5 diagnosis of schizophrenia. The encephaloclastic characteristics of the cyst indicated that it was acquired between the 22nd and 24th gestational weeks, after the major waves of neuronal migration had tapered off. The cyst destroyed the left temporal and occipital lobes, and the inferior parietal lobule. Surprisingly, MS had no evidence of aphasia, alexia, agraphia, or ideational apraxia; in contrast, cognitive functions dependent on the integrity of the right hemisphere were severely impaired. To test the hypothesis that the development of language in MS took place at the expense of functions that are normally carried out by the right hemisphere, we investigated MS’s correlates of oral comprehension with fMRI as a proxy for auditory comprehension and other cognitive functions strongly lateralized to the posterior left hemisphere, such as ideational praxis and reading. Comprehension of spoken language engaged the homologous of Wernicke’s area in the right planum temporale. Porencephaly may represent a natural model of neuroplasticity supervening at predictable epochs of prenatal development.

Apraxia refers to an impairment in the performance of skilled motor acts. This is in the context of normal or near-normal elementary neurological function such as motor power and sensation. In addition a long list of specific exclusions and conditions that may masquerade as apraxia need to be excluded. These include the domains of attention, cognition, motor deficits, and movement disorders

Background and purpose: Although apraxia is a typical consequence of Alzheimer’s disease (AD), the profile of apraxic impairments is still subject to debate. Here, we analysed apraxia components in patients with AD with mild-to-moderate or moderately severe dementia. Methods: Thirty-one patients were included. We first evaluated simple gestures, that is, the imitation of finger and hand configurations, symbolic gestures (recognition, production on verbal command and imitation), pantomimes (recognition, production on verbal command, imitation and production with the object), general knowledge and complex gestures (tool–object association, function–tool association, production of complex actions and knowledge about action sequences). Tests for dementia (Mini Mental State Examination and the Dementia Rating Scale), language disorders, visual agnosia and executive function were also administered. Results: Compared with controls, patients showed significant difficulties (P ≤ 0.01) in subtests relating to simple gestures (except for the recognition and imitation of symbolic gestures). General knowledge about tools, objects and action sequences was less severely impaired. Performance was frequently correlated with the severity of dementia. Multiple-case analyses revealed that (i) the frequency of apraxia depended on the definition used, (ii) ideomotor apraxia was more frequent than ideational apraxia, (iii) conceptual difficulties were slightly more frequent than production difficulties in the early stage of AD and (iv) difficulties in gesture recognition were frequent (especially for pantomimes). Conclusion: Patients with AD can clearly show gesture apraxia from the mild–moderate stage of dementia onwards. Recognition and imitation disorders are relatively frequent (especially for pantomimes). We did not find conceptual difficulties to be the main problem in early-stage AD.

The objective of the study was to determine whether ideational apraxia (IA), a loss of ability to plan the sequence of actions needed to achieve a goal, is associated with Parkinson disease (PD).: The frontal lobes play an important role in planning and sequencing, and many patients with PD have frontal lobe dysfunction.: Ten right-handed patients with PD and 10 right-handed neurologically and psychiatrically healthy people participated. To assess for IA, participants were given sets of pictures that showed the steps in completing a task, but the steps were shown out of order. The participants were required to point to the pictures in the correct sequence to complete each task. The participants also performed a control task of sequencing randomly arranged printed single words to create a sentence that described an accompanying picture.: The patients with PD performed more poorly than the controls on the action-sequencing tasks (P0.05). Errors were predominantly in sequencing rather than repetition or omission, indicating that the poor performance was not caused by perseveration. There were no group differences in the task of sequencing words to make a sentence.: These results indicate that patients with PD do have IA, an action-sequence planning deficit. Further research is needed to better understand mechanisms, ecological implications, and potential treatments.

This study evaluated the impact of distractor objects and their similarity to target objects on everyday task performance in dementia. Twenty participants with dementia due to Alzheimer’s disease (n = 12) or subcortical vascular disease (n = 8) were videotaped while they performed 3 discrete tasks: (1) make a cup of coffee, (2) wrap a gift, and (3) pack a lunch under two conditions that were counterbalanced across participants. The conditions differed in terms of the type of distractor objects included in the workspace: (1) Target-Related Distractor Condition - distractor objects were functionally and visually similar to target objects (e.g., salt for sugar) (2) Unrelated Distractor Condition - distractors were neither visually nor functionally similar to targets (e.g., glue for sugar). Participants touched (t = 4.19; p < .01) and used (z = 3.00; p < .01) significantly more distractors, made more distractor errors (i.e., substitutions; t = 2.93; p < .01), and took longer to complete tasks (t = 2.27; p < .05) in the Target-Related Distractor condition. The percent of steps accomplished and non-distractor errors did not differ across conditions (t < 1.26; p > .05 for both). In summary, distractors that were similar to targets elicited significant interference effects circumscribed to object selection. (JINS, 2010, 16, 484–494.)

Objective: To determine praxis function in patients with Parkinson’s disease (PD) and multiple system atrophy (MSA). Methods: Nineteen patients with PD and 16 patients with probable MSA were recruited into study. Twenty-five age-matched, healthy subjects were included as controls. The Mayo Clinic praxis test battery was applied. Pantomime tasks, including oral/facial, trunk, and upper extremity movement, were used to evaluate ideomotor apraxia (IMA). Sequential tasks, including Luria test for ideational apraxia (IDA) and use of actual objects, were also tested. In addition, Standardized Mini Mental Test (MMSE), Hamilton Depression (HAM-D), and Anxiety (HAM-A) Scales were used. Results: Mean ages of the study participants were 66 ± 7, 68 ± 5, and 65 ± 7 years in PD, MSA, and control groups, respectively. Mean total praxis score was significantly lower for patients with PD (92.4 ± 4) and MSA (75.9 ± 18) than for controls (97.4 ± 2) (P = 0.000). Transitive performances of upper extremities and sequential tasks were significantly impaired in patients with PD compared to control subjects (P

Apraxias are disorders of motor cognition that cannot be explained by basic sensorimotor deficits or aphasia. The relatively high frequency of apraxia (approximately half of all patients with left-hemispheric stroke suffer from apraxia during the acute phase) as well as its prognostic value for determining the outcome of rehabilitative therapy clearly convey the necessity of more comprehensive research into the pathophysiology of apraxia in order to develop new therapeutic strategies. In recent years, functional imaging (PET and fMRI) has helped to provide important new insights into the pathophysiology of ideomotor apraxia (defective movement plan) and ideational apraxia (defective action concept). In this review, the neural bases for the clinically observed dissociations between the imitation of abstract and symbolic movements (as in ideomotor apraxia) and for the object-trigger system (which is disturbed in ideational apraxia) will be exemplified. Furthermore, we will recapitulate recent studies that provide evidence for the complementary functions of the right and left parietal cortices in the spatial and temporal organization of complex, object-related actions. The particular importance of the left parietal cortex for motor cognition is further supported by studies examining the integration of spatial and temporal movement information during the generation of a movement plan as well as by the generation of such movement plans in the left parietal cortex independent from the hand that executes the movement.

Relative to our understanding of the memory and language deficits associated with Alzheimer's disease (AD), little is known about problems with everyday action performance (i.e., meal preparation, grooming). The resource theory proposes that everyday action problems are best explained by a unitary deficit in general cognitive resources. However, recent research suggests that omission and commission errors may reflect dissociable aspects of action impairment, with only omissions associated with resource limitations. This study examined everyday action performance in 70 participants with AD who also underwent a neuropsychological evaluation. First, correlation and principal component analyses were performed to examine the construct(s) that might explain everyday action impairment. Second, relations between everyday task component(s) and neuropsychological tests were examined by using correlation and regression analyses. Third, differences in everyday action error patterns were examined among participants of comparable overall impairment levels. Results showed omission and commission errors were uncorrelated and distinct components of everyday action performance, predicted by different neuropsychological tests, and differentially distributed even among participants with comparable overall impairment.

Background Upper limb apraxia is a common disorder associated with stroke that can reduce patients’ independence levels in activities of daily living and increase levels of disability. Traditional rehabilitation programs designed to promote the recovery of upper limb function have mainly focused on restorative or compensatory approaches. However, no previous studies have been completed that evaluate a combined intervention method approach, where patients concurrently receive cognitive training and learn compensatory strategies for enhancing daily living activities. Methods/Design This study will use a two-arm, assessor-blinded, parallel, randomized controlled trial design, involving 40 patients who present a left- or right-sided unilateral vascular lesion poststroke and a clinical diagnosis of upper limb apraxia. Participants will be randomized to either a combined functional rehabilitation or a traditional health education group. The experimental group will receive an 8-week combined functional program at home, including physical and occupational therapy focused on restorative and compensatory techniques for upper limb apraxia, 3 days per week in 30-min intervention periods. The control group will receive a conventional health education program once a month over 8 weeks, based on improving awareness of physical and functional limitations and facilitating the adaptation of patients to the home. Study outcomes will be assessed immediately postintervention and at the 2-month follow-up. The primary outcome measure will be basic activities of daily living skills as assessed with the Barthel Index. Secondary outcome measures will include the following: 1) the Lawton and Brody Instrumental Activities of Daily Living Scale, 2) the Observation and Scoring of ADL-Activities, 3) the De Renzi Test for Ideational Apraxia, 4) the De Renzi Test for Ideomotor Apraxia, 5) Recognition of Gestures, 6) the Test of Upper Limb Apraxia (TULIA), and 7) the Quality of Life Scale For Stroke (ECVI-38). Discussion This trial is expected to clarify the effectiveness of a combined functional rehabilitation approach compared to a conservative intervention for improving upper limb movement and function in poststroke patients. Trial registration Clinical Trial Gov number NCT02199093. The protocol registration was received 23 July 2014. Participant enrollment began on 1 May 2014. The trial is expected to be completed in March 2016. Electronic supplementary material The online version of this article (doi:10.1186/s13063-015-1034-1) contains supplementary material, which is available to authorized users.

Limb apraxia, a disorder of higher order motor control, has long been a challenge for clinical assessment and understanding (Leiguarda and Marsden, 2000). The deficits originally described in limb apraxia (Liepmann, 1920) have been classified by the nature of the errors made by the patients leading to, namely, ideational and ideomotor apraxia. The dual stream hypothesis (Goodale and Milner, 1992) has been used to explain these categories: ideational apraxia is thought to relate to a deficit in the concept of a movement (coded in the ventral stream). Patients have difficulty using objects, sequencing actions to interact with them or pantomiming their use. Ideomotor apraxia, on the other hand, is thought to arise from problems in the accurate implementation of movements within the dorsal stream. One of the limitations on understanding apraxia is the failure by the clinical literature to draw on knowledge of the factors determining actions in the environment. Here we emphasize the role of affordance. There is much recent work indicating that our responses to stimuli are strongly influenced by the actions that the objects "afford", based on their physical properties and the intentions of the actor (e.g., Tucker and Ellis, 1998). The concept of affordance, originally suggested by Gibson (1979) has been incorporated in a recent model of interactive behavior that draws from findings in non-human primates, namely the "affordance competition hypothesis" (Cisek, 2007). This postulates that interactive behavior arises by a process of competition between possible actions elicited by the environment. In this paper we argue that "affordance competition" may play a role in apraxia. We review evidence that at least some aspects of apraxia may reflect an abnormal sensitivity to competition when multiple affordances are present (Riddoch et al., 1998) and/or a poor ability to exert cognitive control over this competition when it occurs. This framework suggests a new way of conceptualizing deficits in apraxia which invites further investigations in the field.

Background In contrast to frontotemporal lobar degeneration, atrophy of the focal posterior lateral cortex has not been thoroughly studied. Three clinical types of focal cortical atrophy have been described: 1) logopenic variant of primary progressive aphasia, which presents with impaired repetition despite normal articulation; 2) posterior cortical atrophy, which presents with prominent visuospatial deficits; and 3) primary progressive apraxia. All three clinical types are characterized by specific patterns of hypometabolism/hypoperfusion: the left posterior perisylvian area in the logopenic variant of primary progressive aphasia, bilateral parietooccipital areas in posterior cortical atrophy, and the parietal cortex in primary progressive apraxia. However, not every patient clearly fits into one of these categories. Case presentation Here we describe two patients with atypical focal cortical presentations. They presented with a history of a few years of progressive transcortical sensory aphasia characterized by fluent output with normal grammar and syntax, normal repetition, sentence comprehension deficits, and anomia without loss of word meaning. They also presented with progressive apraxia that began at the initial stages. Some forms of posterior symptoms including acalculia, agraphia, and visuospatial deficits were also observed. Hypoperfusion was noted mainly in the left temporoparietal region, which is slightly posterior to the perisylvian area. Conclusions Although our cases lack in CSF findings and PIB scan, these two cases and previous reports might suggest the existence of a subgroup of patients presenting with transcortical sensory aphasia, apraxia, and posterior symptoms (acalculia, agraphia, and visuospatial deficits) in the setting of Alzheimer’s disease. This subgroup may reflect the spectrum of clinical manifestations between logopenic variant of primary progressive aphasia and posterior cortical atrophy.

Variably protease-sensitive prionopathy (VPSPr) is a recently described neurodegenerative disorder characterised by the presence of spongiform encephalopathy and an unusual immunostaining and immunoblotting pattern for the disease-associated prion protein (PrPSc).1 This links VPSPr to human prion diseases, which are uniformly fatal disorders. The clinical symptoms and the longer duration of illness make VPSPr distinct from sporadic or idiopathic Creutzfeldt-Jakob disease (sCJD).1 Doxycycline treatment has been evaluated in patients with prion disease, however, there is little evidence that it can reverse the clinical symptoms or reduce the underlying disease progression once established.2 We present a patient with VPSPr who received doxycycline and survived for an extended period of time in an akinetic and mute state. Neuropathological examination was performed using published methods and various anti-PrP antibodies.3 Frozen tissues from selected brain regions were available for biochemical analysis. Tissues were analysed for the presence of protease-resistant PrP (PrPres) as previously described (see online supplementary material).4 In May 2007, a registered psychiatrist suspected an organic affective disorder in a 54-year-old Austrian woman. Two months earlier, medical work-up for presumed weight loss of 16 kg within the past 18 months had been unremarkable. In June 2007, the patient was admitted to a clinic that specialised in disorders of the nervous system. Her family history was negative for neurodegenerative diseases and there was no evidence of exposure to toxins. She reported depressed mood and short-term memory problems, and difficulties with balance, walking, driving and cooking. On neuropsychological examination she was oriented to time, place, person and situation, Mini-Mental State Examination score was 22/30, clock drawing test score was 3/9. She had word-finding difficulties, ideational apraxia, acalculia and visuoconstructive deficits. She displayed affective incontinence with crying fits. She had gait ataxia, and extensor plantar responses were observed with increased tone …

Apraxic phenomena occur in various neurological conditions. Selective motion control is viewed as the basic capacity to make fine and precise, isolated or independent face or limb movements. Its deficit can indicate limb-kinetic apraxia if it is not explained by paresis, somatosensory deafferentation, or ataxia. The core deficit in ideomotor apraxia could be deficient movement representations, i.e. the combination of invariant features of intrinsic and extrinsic coding for a given movement, which are most important when movements have to be performed outside their typical context. Ideational apraxia would be defined by a semantic deficit related to action. Frontal apraxia is characterised by an action-sequencing deficit. A detailed model is proposed regarding processes relevant to praxis.

In the present study we analysed the perseverative behaviour of three apraxic patients (FG, CEO, and VCR) while they were pantomiming the use of common objects and during their real use. The three patients were found to perseverate from one trial to later ones aspects of a given action in the pantomiming and in real use tasks. In particular, our main result was a striking double dissociation between patients in perseverating hand and arm movements. Patients FG and CEO made more perseveration errors involving the hand than VCR did, whereas the perseverative errors made by VCR involving the arm were more numerous than those made by FG and CEO. The patients differed also in other aspects of the perseverations, e.g., their median lags. Results are used to exend previous theories developed in the linguistic domain to that of actions.

Contains fulltext : 54642.pdf (Publisher’s version ) (Closed access) The present study compared imitation performance in patients with ideomotor apraxia (IMA), eight right hemispheric-damaged patients, and eight control participants without neurological damage in three experiments. Experiment 1 confirmed in the Goldenberg test that IMA patients were particularly impaired in hand gestures and combined finger and hand gestures, but not in the imitation of finger gestures, compared to the other two groups. Experiment 2, however, demonstrated that finger selection is not per se preserved in imitative behaviour in patients with IMA. Experiment 3 confirmed this finding in an experiment under visual control. Together, the results add evidence to the idea that imitation should be viewed from a goal-directed rather than a body-mapping perspective, and that highest priority is given to more distal aspects of imitation as reaching for the correct object, rather than the means used to achieve the goal of a modelled action.

We report three PET experiments that examine the neural substrates of the conceptual components of action retrieval. In all three experiments, subjects made action or screen-size decisions to familiar objects presented either as pictures or written words (the names ofthe objects). In Experiment 1, a third task was included, requiring a decision on the real-life size of the stimuli. In Experiment 2, a third stimulus type was included, with action and size decisions also performed on pictures of meaningless novel objects. Finally, in Experiment 3, we changed the response mode from a button press to a more explicit movement made with a lsquo;lsquo;manipulandumlsquo;lsquo;. Based on neuropsychological findings, we predicted that when action responses were made to pictures of familiar or novel objects, relative to words, there would be less activation in semantic regions but greater activation in visual, motor, and perhaps parietal cor tices. We found that, action relative to screen-size decisions on both pictures and words activated the left hemisphere temporo-frontal semantic system with activation in the left posterior middle temporal cortex specific to action retrieval (Experiment 1). In addition, action retrieval elicited more activation for (1) words than pictures in areas associated with semantics; and (2) novel objects than words or familiar objects in areas associated with pre-semantic object processing. These results are discussed in the context of semantic and visual routes to action retrieval.