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Denis Jabaudon

Publications and source records attributed to Denis Jabaudon.

7 recordsLinked to original sources

Preattentive interference between touch and audition: a case study on multisensory alloesthesia.

Alloesthesia is a rare clinical condition that corresponds to a spatial disorder of stimulus localization, in which patients experience a given stimulus on the side opposite to the side of stimulation. Whereas it has been mostly described for unisensory stimulations, evidence of multisensory alloesthesia is only anecdotal. Here, we investigated a case of multisensory auditory-tactile alloesthesia. Our data suggest that auditory-tactile integration and multisensory alloesthesia not only depend on attentional mechanisms, but also on somatotopic preattentive mechanisms.

Acoustic Stimulation↗

Reaching beyond the midline: why are human brains cross wired?

The crossing of nerve tracts from one hemisphere in the brain to the contralateral sense organ or limb is a common pattern throughout the CNS, which occurs at specialised bridging points called decussations or commissures. Evolutionary and teleological arguments suggest that midline crossing emerged in response to distinct physiological and anatomical constraints. Several genetic and developmental disorders involve crossing defects or mirror movements, including Kallmann's and Klippel-Feil syndrome, and further defects can also result from injury. Crossed pathways are also involved in recovery after CNS lesions and may allow for compensation for damaged areas. The development of decussation is under the control of a host of signalling molecules. Growing understanding of the molecular processes underlying the formation of these structures offers hope for new diagnostic and therapeutic interventions.

Animals↗

Usefulness of ambulatory 7-day ECG monitoring for the detection of atrial fibrillation and flutter after acute stroke and transient ischemic attack.

BACKGROUND AND PURPOSE: Although atrial fibrillation is the most frequent cause of cardioembolic stroke, this arrhythmia remains underdiagnosed, as it is often asymptomatic or intermittent and, thus, may not be detected on standard 12-lead ECG or even 24-hour ECG recording (Holter). In this study, we hypothesized that 7-day ambulatory ECG monitoring using an event-loop recording (ELR) device would detect otherwise occult episodes atrial fibrillation and flutter (AF) after acute stroke or transient ischemic attack (TIA). METHODS: One hundred forty-nine consecutive patients admitted to our neurology department with an acute stroke or TIA were systematically screened for emboligenic arrhythmias using standard ECG. In the absence of AF on standard ECG, patients underwent 24-hour ECG recording (Holter), which was followed by a 7-day ambulatory ECG monitoring (ELR) in patients with a normal Holter. Patients with previously documented persistent AF, with primary hemorrhagic stroke, or with acute large vessel dissection were not included in the study. RESULTS: AF was detected in 22 patients. Standard ECG identified AF in 2.7% of the cases at admission (4/149 patients) and in 4.1% of remaining patients within 5 days (6/145). Holter disclosed AF in 5% of patients with a normal standard ECG (7/139 patients), whereas ELR detected AF in 5.7% of patients with a normal standard ECG and normal Holter (5/88 patients). CONCLUSIONS: Following acute stroke or TIA, ELR identified patients with AF, which remained undetected with standard ECG and with Holter. ELR should, therefore, be considered in every patient in whom a cardioembolic mechanism is suspected.

Adult↗

Pathogenesis and diagnostic pitfalls of ventricular diverticula: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Ventricular diverticula are local herniations of the ventricular system occurring in association with severe, long-standing hydrocephalus. Variability in the extent and location of these ventricular pouches may produce misleading radiological conformations and raise diagnostic challenges. In this report, we discuss the pathogenesis and differential diagnosis of ventricular diverticula on the basis of a case illustration. CLINICAL PRESENTATION: We report the case of a 38-year-old woman presenting with hydrocephalus secondary to an obstructive lesion of the third ventricle. A large, dilated structure compressing the brainstem was present in the posterior fossa. INTERVENTION: The posterior fossa lesion was identified as an atrial diverticulum by injection of contrast medium into the right lateral ventricle, which led to immediate enhancement of the infratentorial cavity. Ventricular drainage and removal of the third ventricular lesion, a colloid cyst, allowed progressive collapse of the diverticulum and symptom resolution. CONCLUSION: This report discusses the pathogenesis of ventricular diverticula and demonstrates that ventriculography can be used to differentiate atrial diverticula from other posterior fossa lesions when time-consuming multiplanar magnetic resonance imaging cannot be afforded on an emergency basis.

Adult↗

Cooperation between independent hippocampal synapses is controlled by glutamate uptake.

Localized action of released neurotransmitters is the basis for synaptic independence. In the hippocampal neuropil, where synapses are densely packed, it has been postulated that released glutamate, by diffusing out of the synaptic cleft, may also activate postsynaptic receptors at neighboring synapses. Here we show that neighboring excitatory synapses on hippocampal CA1 pyramidal cells can cooperate in the activation of postsynaptic receptors through the confluence of released glutamate, and that this cooperation is controlled by glutamate uptake. Furthermore, glutamate transporters control temporal interactions between transmitter transients originating from the same axon. Thus, cooperative interactions between excitatory synapses are modulated in space and time by glutamate uptake.

Animals↗