The use of a detailed video-based locomotor pattern analysis system to assess the functional reinnervation of denervated hind limb muscles.

BACKGROUND: Spinal cord injuries induce a critical loss of motoneurons followed by irreversible locomotor function impairment. Surgical approaches combined with neuroprotective agents effectively rescue the damaged motoneurons and improve locomotor function. Our aim was to develop a reliable method which is able to provide quantifiable and in-depth data on the locomotor recovery during skeletal muscle reinnervation. NEW METHOD: Sprague-Dawley rats underwent lumbar 4 ventral root avulsion and reimplantation followed by riluzole treatment in order to rescue the injured motoneurons of the damaged pool. Control animals were operated, but received no riluzole treatment. The locomotor pattern of the hind limb was recorded biweekly on a special runway equipped with high resolution and high speed digital cameras producing both lateral and rear views simultaneously. All together 12 parameters of the hind limb movement pattern were evaluated by measuring specific joint angles, footprints and gait parameters in single video frames. Four months after the operation Fast Blue, a fluorescent retrograde tracer was applied to the L4 spinal nerve in order to label the reinnervating motoneurons. RESULTS: Our results confirmed the sensitivity of our arrangement and established strong relationship between the functional improvement and the morphological reinnervation. Moreover, we developed a correction method to make the system tolerant to the differences in the weight, step duration and step length. COMPARISON WITH EXISTING METHODS: There are no commercially available cheap, multi-parametric analysing equipment to characterise the gait in its complexity. CONCLUSIONS: Our system offers a modular, adaptable and expandable analysis on the reinnervation of the limb musculature in rodents.

The German health care Innovation Fund - An incentive for innovations to promote the integration of health care.

PURPOSE: Many health systems face challenges such as rising costs and lacking quality, both of which can be addressed by improving the integration of different health care sectors and professions. The purpose of this viewpoint is to present the German health care Innovation Fund (IF) initiated by the Federal Government to support the development and diffusion of integrated health care. DESIGN/METHODOLOGY/APPROACH: This article describes the design and rationale of the IF in detail and provides first insights into its limitations, acceptance and implementation by relevant stakeholders. FINDINGS: In its first period, the IF offered € 1.2 billion as start-up funding for model implementation and evaluation over a period of four years (2016-2019). This period was recently extended to a second round until 2024, offering € 200 million a year as from 2020. The IF is triggering the support of relevant insurers for the development of new integrated care models. In addition, strict evaluation requirements have led to a large number of health service research projects which assess structural and process improvements and thus enable evidence-based policy decisions. ORIGINALITY/VALUE: This article is the first of its kind to present the German IF to the international readership. The IF is a political initiative through which to foster innovations and promote integrated health care.

Delayed Spinal Cord-Brachial Plexus Reconnection after C7 Ventral Root Avulsion: The Effect of Reinnervating Motoneurons Rescued by Riluzole Treatment.

Ventral root avulsion induces dramatic loss of the affected spinal cord motoneurons. The neuroprotective effect of riluzole has been previously proven on the injured motoneurons: the vast majority of them can be rescued even when they have no possibility to regenerate their axons. In this study the number of injured motoneurons rescued by riluzole treatment and their capacity to reinnervate the denervated forelimb muscles was investigated. Surgical reconnection with a peripheral nerve graft between the affected spinal cord segment and the C7 spinal nerve was established immediately or with 1- and 3-week delay after avulsion. Avulsion and immediate reconnection of the motoneuron pool to the spinal nerve resulted in moderate reinnervation of the spinal nerve (281 ± 23 standard error of mean [SEM] retrogradely labeled motoneurons), whereas treatment of the injured motoneurons with riluzole yielded considerably higher numbers of reinnervating motoneurons (548 ± 18 SEM). Reconnection of the motor pool with the C7 spinal nerve with 1-week delay allowed fewer motor axons to reinnervate their targets in control and riluzole-treated animals (159 ± 21 vs. 395 ± 16 SEM). A clinically relevant 3-week delay in reconnection further reduced the number of reinnervating motoneurons (76 ± 22 SEM), but riluzole pre-treatment still enabled a significant number of rescued motoneurons (396 ± 17 SEM) to regenerate their axons into the C7 spinal nerve. These results show that those injured adult motoneurons that are rescued by riluzole treatment started immediately after the avulsion injury are able to reinnervate their targets even if they are provided with a conduit several weeks after the primary injury. This finding suggests that partial rescue of injured motoneurons with riluzole in patients who suffered a brachial plexus avulsion injury may provide an available pool of surviving motoneurons for late reconnection/reimplantation surgeries.

Naming of musical notes: a selective deficit in one musical clef.

We investigated the ability to perform solfeggio, i.e. oral reading of musical notes in MP, a 65 year-old female professional musician, who, following a left temporoparietal ischemia, showed a complex pattern of amusia. The deficit on which we focused was her inability to read orally the bass (F) clef, often substituting it with the violin (G) clef. This problem could not be attributed to a lack of comprehension. The patient could in fact correctly perform on the piano the same sequences she erroneously read aloud; she was also able to correctly judge whether two strings, one in bass clef and the other in violin clef, represented the same sequence of notes. The problem seems to lie in the inability to retrieve note names keeping into account the clef-rule. It is hypothesized that, in the production of note names, this function requires the identification and application of syntactic-like information, in analogy with what is thought to happen in the retrieval of other words.

Door but not four and 4 a category specific transcoding deficit in a pure acalculic patient.

We report a left parietal damaged, acalculic, non aphasic patient who showed a specific deficit in reading Arabic and spelled-out numerals. Word reading was flawless, while he showed a severe impairment in reading meaningless strings of phonemes (phonological alexia). He also showed a dissociation between the preserved ability to retrieve knowledge about general facts and the impairment in retrieving cardinal, personal and non-personal numerical facts. These findings point to a separate organization in the brain of the numerical domain.

A category-specific deficit of spatial representation: the case of autotopagnosia.

Following a vascular lesion in the parietal cortex of the language dominant hemisphere (right in one case), two patients showed a striking dissociation between spared naming, recognition and use of their body parts and an inability in localising on verbal command the same body parts on themselves and on a mannequin (Autotopagnosia, AT). The patients were submitted to a modified version of Reed and Farah Test (1995), a test that taps the ability to encode changes of body position as opposed to changes of position of objects. Their performance differed from normal controls, showing a specific deficit in encoding body position. It is suggested that AT could be the consequence of a lesion in a specific neural circuit, located in the language dominant hemisphere, whose function is to encode the body position for both oneself and others.

Titanium-niobium, a new finishing wire alloy.

The mechanical properties of the newly introduced titanium-niobium finishing wires were investigated. Both in bending and torsional loading mode, the stiffness, yield point, post-yield behavior, and springback of titanium-niobium wires were experimentally determined and compared to those of equally sized stainless steel wires. The experimentally obtained values were also validated with theoretical values from engineering formulas of cantilever deformations. The ratios for these parameters for the two materials proved to be different in bending and torsion. The stiffness of titanium-niobium in bending is roughly half of that of stainless steel, whereas in torsion it is roughly one-third. These characteristics enable the clinician to use titanium-niobium for creative bends without the excessive force levels of steel wires. The springback of titanium-niobium in bending is 14% lower than that of steel, whereas in torsion it is about the same or even slightly higher than that of steel, thus making it possible to utilize the wire for even major third-order corrections. Finally, the weldability of titanium-niobium wires was found to be good, so it is possible to weld wires of different dimensions together for the generation of differentiated force systems.

Numerical skills and aphasia.

The aim of this study was to investigate numerical difficulties in 50 patients with left hemispheric lesions. Aphasic patients were grouped according to their type of aphasia diagnosed by the Aachener Aphasia Test. The overall error rate in various transcoding and calculation tasks was clearly correlated with the severity of the language deficit, global aphasics being the most impaired patients. Broca's and Wernicke's aphasics scored similarly at the quantitative level, and amnesic aphasics were less impaired. Interestingly, qualitative analysis of the errors indicated that each group presented with specific difficulties, partially reflecting the nature of the language problems. In simple calculation, multiplication was found to be the most impaired operation, in particular in Broca's aphasics. This result supports the hypothesis that the retrieval of multiplication facts is preferentially mediated by verbal processing. Calculation procedures were mainly impaired in Wernicke's and global aphasics.

The breakdown of calculation procedures in Alzheimer's disease.

The study investigates calculation abilities in 12 patients with probable Alzheimer's disease (AD) and compares them to calculation abilities of healthy control subjects (NC) and patients with focal left hemisphere lesions (LHL). AD patients scored significantly lower than NC in all calculation tasks and lower than LHL patients in the execution of complex written calculation, but not in the retrieval of arithmetic facts. In the AD group a subject-by-subject error analysis on the complex written calculation showed a low consistency and a high variability of error types. It is suggested that AD patients' difficulties in complex calculation arise from a monitoring deficit and not from incomplete or distorted calculation algorithms. Overall, deficits in monitoring calculation procedures may be an early and common symptom of AD.

Writing arabic numerals in an agraphic patient.

We report on the writing of Arabic numerals in a patient whose alphabetical script was restricted to graphemic jargon (Schonauer & Denes, 1994). The analysis of writing errors in Arabic script over three testing sessions (4, 10, and 13 months after stroke) confirmed the separate processing of syntactic and lexical information in number production proposed by current models. The changing error pattern over time reflected some difficulties observed in developmental studies on the acquisition of Arabic numeral writing. Errors were mostly of the syntactic type and (at a certain stage) were based on the verbal form of the numerals. As reported in neuropsychological (Noel & Seron, 1995) and developmental (Power & Dal Martello, 1990; Seron & Fayol, 1994) studies, sum relations were more difficult to transcode than product relations within complex numerals.

Temporal gradient in confabulation.

We report on a patient, PL, who developed an amnesic confabulatory syndrome following heart arrest. PL's confabulation occurred both in episodic and semantic memory tasks. In a task in which she was asked to identify photographs of people and events highly familiar to her, a temporal gradient on her performance emerged. Confabulation was massive for the recognition of photographs from the eighties and decreased consistently for the recognition of photographs representing people and events from earlier decades. Correct responses, in contrast, were distributed according to an opposite pattern. Correct recognition was very high for photographs from the fifties but consistently decreased for photographs from the following decades. These results are discussed in terms of the co-occurrence and interaction of preserved awareness of the personal past and impaired ability to access less stable memories. These results also suggest that memories are not stored randomly but according to a temporal criterion that presumably reflects the relative strength and stability of stored episodic memories.

Limb-kinetic apraxia.

Five cases of limb-kinetic apraxia following primary degenerative cerebral pathology are reported. Apraxia appeared as the main symptom and was not concomitant to aphasia or to widespread cognitive impairments. Apraxia was not a consequence of elementary motor or sensory deficits, lack of coordination, or the result of the presence of rigid-akinetic symptoms. The apraxia was usually unilateral, being present in both routine activities and testing sessions and consisting of the coarse, unilateral, awkward execution of correctly planned movements. Conceptual knowledge of the movements and their ideational plan was spared. The characteristics of apraxia fit the definition of limb-kinetic apraxia originally proposed by Liepmann. The pertinent literature is reviewed.

Multiple-domain dissociation between impaired visual perception and preserved mental imagery in a patient with bilateral extrastriate lesions.

A brain-damaged patient is described whose pattern of performance provides insight into both the functional mechanisms and the neural structures involved in visual mental imagery. The patient became severely agnosic, alexic, achromatopsic and prosopagnosic following bilateral brain lesions in the temporo-occipital cortex. However, her mental imagery for the same visual entities that she could not perceive was perfectly preserved. This clear-cut dissociation held across all the major domains of high-level vision: object recognition, reading, colour and face processing. Our findings, together with other reports on domain-specific dissociations and functional brain imaging studies, provide evidence to support the view that visual perception and visual mental imagery are subserved by independent functional mechanisms, which do not share the same cortical implementation. In particular, our results suggest that mental imagery abilities need not be mediated by early visual cortices.

G.B. Vico, precursor of cognitive neuropsychology? The first reported case of noun-verb dissociation following brain damage.

The first case of selective impairment in retrieving verbs in comparison to nouns, following brain damage, was reported in 1744 by the Neapolitan philosopher G. B. Vico. He considered such observation experimental evidence of the correctness of his theory on mental organization of language, thus anticipating the methods of cognitive neuropsychology.

Preserved imagery for colours in a patient with cerebral achromatopsia.

We report the case of a patient who, after sequential bilateral strokes in the occipital regions sparing the primary visual cortex, developed a severe deficit of colour perception. At variance with other reports of acquired achromatopsic patients, she showed a perfectly vivid visual imagery for colours. These findings, together with similar data in domains other than colour processing, challenge the theories which posit that the same cognitive processes are involved in both the perception and the retrieval from memory of a given stimulus.

Remembering and knowing the past: a case study of isolated retrograde amnesia.

We describe a patient, RM, who suddenly became amnesic for premorbid autobiographic events in the absence of any known precipitating event. Learning abilities as well as semantic knowledge were normal. Knowledge of famous facts and persons was good, although not perfect. Whether RM suffered from organic or psychogenic isolated retrograde amnesia (IRA) could not be established on the basis of available clinical and neuropsychological elements. Regardless of its aetiology, RM's case respects the boundaries between semantic and episodic memory and so gives further support to the distinction between these two memory systems.

Reversible aphasia in adolescence: A late-onset form of Landau Kleffner syndrome? Report of a single case.

An adolescent boy developed a long-lasting pattern of global aphasia, concomitant to focal (left temporal) EEG abnormalities; this was followed by complete recovery. Laboratory and neuroimaging studies were within normal limits. The possibility of a late-onset Landau Kleffner syndrome is discussed.

Semantic and episodic memory in aphasia.

Within the framework of the distinction between episodic and semantic memory, it has been argued that these two memory Systems are organised in a hierarchical way. The hierarchical hypothesis assumes that episodic memory is a specific subsystem of semantic memory and therefore implies that episodic memory cannot exist without semantic memory. If this hypothesis is correct, it should be expected that (episodic) yes/no recognition performance would improve in patients with preserved semantic memory, following semantic encoding. In the present study we investigated the influence of semantic encoding on recognition memory performance in a population of 28 aphasic patients (AA) and 14 normal controls (NC). Experiment 1 considered recognition memory for semantically unrelated items, whereas Experiments 2 and 3 assessed recognition memory for semantically related items. In Experiment 3, but not in Experiment 2, subjects were explicitly instructed to make a semantic association between the items. AA were impaired, compared to NC, only on the recognition memory performance of Experiment 1. The ability to make a semantic association between two items was significantly and positively correlated to the ability to recognise, in a subsequent test, those same items. A further analysis showed that patients who were impaired on the semantic association task did significantly worse on the recognition task of Experiment 3 than NC and than patients who were unimpaired on the semantic association task. These findings are discussed in the context of memory deficits in aphasia and interpreted as giving support to the view that episodic memory for an item is affected by the level of semantic awareness of that same item.