We report on a pilot study exploring whether blood immune signatures can reveal early specific indicator profiles for patients meeting sepsis criteria upon hospital admission. We analysed samples of sepsis-suspected patients (N=20) and age-spanning healthy controls (N=12), using flow cytometry-based assays. We measured inflammatory markers from plasma fractions, and immunophenotyped freshly isolated unfixed PBMCs for leukocytes subsets representation and expression of activation markers, including chemokine receptors.
View Article and Find Full Text PDFWe studied simultaneous EMG and midline EEG responses, including over the cerebellum, in 10 standing subjects (35 ± 15 yr; 5 females, 5 males). Recordings were made following repeated taps to the sternum, stimuli known to evoke short-latency EMG responses in leg muscles, consistent with postural reflexes. EEG power had relatively more high-frequency components (>30 Hz) when recorded from electrodes over the cerebellum (Iz and SIz) compared with other midline electrodes.
View Article and Find Full Text PDFWe report an experiment to investigate the role of the cerebellum and cerebrum in motor learning of timed movements. Eleven healthy human subjects were recruited to perform two experiments, the first was a classical eye-blink conditioning procedure with an auditory tone as conditional stimulus (CS) and vestibular unconditional stimulus (US) in the form of a double head-tap. In the second experiment, subjects were asked to blink voluntarily in synchrony with the double head-tap US preceded by a CS, a form of Ivanov-Smolensky conditioning in which a command or instruction is associated with the US.
View Article and Find Full Text PDFThe cerebellum is known to have extensive reciprocal connectivity with the cerebral cortex, including with prefrontal and posterior parietal cortex, which play an important role on the planning and execution of voluntary movement. In the present article we report an exploratory non-invasive electrophysiological study of the activity of the cerebellum and cerebrum during voluntary finger and foot movements. In a sample of five healthy adult subjects, we recorded EEG and the electro-cerebellogram (ECeG) with a 10% cerebellar extension montage during voluntary left and right index finger and foot movements.
View Article and Find Full Text PDFThe cerebellum plays a critical role in the modulation of vestibular reflexes, dependent on input from proprioceptive afferents. The mechanism of this cerebellar control is not well understood. In a sample of 11 healthy human subjects, we investigated the effects of head orientation on ocular, cervical, postural and cerebellar short latency potentials evoked by impulsive stimuli applied at both mastoids and midline skull sites.
View Article and Find Full Text PDFWe report the results of an experiment in which electrophysiological activity was recorded from the human cerebellum and cerebrum in a sample of 14 healthy subjects before, during and after a classical eye blink conditioning procedure with an auditory tone as conditional stimulus and a maxillary nerve unconditional stimulus. The primary aim was to show changes in the cerebellum and cerebrum correlated with behavioral ocular responses. Electrodes recorded EMG and EOG at peri-ocular sites, EEG from over the frontal eye-fields and the electrocerebellogram (ECeG) from over the posterior fossa.
View Article and Find Full Text PDFWe present an initial report using 5 subjects, of short and long latency collic evoked responses following a half cycle of 100 Hz vibration (5 ms) applied to the sternocleidomastoid (SCM) tendon. These were detected in EEG and extraocular and leg muscles and compared with vestibular-dependent responses from direct mastoid stimulation. The responses from the extraocular recording site are likely to be evoked myogenic potentials, thus "collic evoked myogenic potentials" (CEMPs).
View Article and Find Full Text PDFRecordings from over the posterior fossa following impulsive acceleration stimuli have shown short latency evoked potentials of presumed cerebellar origin. In this study, we investigated the effect of posture on these cerebellar evoked potentials (CEPs) and their relationship to postural reflexes recorded from the leg muscles evoked by the same stimuli. Nine healthy subjects were tested during lying (supine and prone), sitting and standing.
View Article and Find Full Text PDFWe studied nine normal volunteers with a classical conditioning paradigm using a mastoid tap, believed to activate otolith receptors, as an unconditional stimulus (US) and the consequent blink as the unconditioned response (UR). Both visual (alternation of stripes) and an auditory tone were used as conditional stimuli (CS). Recordings were made below the eyes at IO1 and IO2, from over the frontal eye fields (C3' and C4') and over the posterior fossa, the latter at sites we have previously reported that we were able to record an evoked climbing fibre response (CFR) at short latency.
View Article and Find Full Text PDFIn this work we examine the possible neural basis for two brainstem-spinal reflexes using source analyses of brain activity recorded over the cortex and posterior fossa. In a sample of 5 healthy adult subjects, using axial and vestibular stimulation by means of applied impulsive forces, evoked potentials were recorded with 63 channels using a 10 % cerebellar extension montage. In parallel, EMG was recorded from soleus and tibialis anterior muscles and accelerometry from the lower leg.
View Article and Find Full Text PDFBackground: Screening for SARS-CoV-2 antibodies is under way in some key worker groups; how this adds to self-reported COVID-19 illness is unclear. In this study, we investigate the association between self-reported belief of COVID-19 illness and seropositivity.
Methods: Cross-sectional study of three key worker streams comprising (A) Police and Fire & Rescue (2 sites) (B) healthcare workers (1 site) and (C) healthcare workers with previously positive PCR result (5 sites).
Many bacterial species readily develop biofilms that act as a protective matrix against external challenge, e.g., from antimicrobial treatment.
View Article and Find Full Text PDFIn the original publication of the article, Fig. 3 is incorrect.
View Article and Find Full Text PDFVestibular cerebellar evoked potentials (VsCEPs) were recorded from over the occipital and cerebellar regions of the scalp using bone-conducted (BC) stimuli applied at the mastoids (impulsive accelerations and 500 Hz) and 500 Hz acoustic tones (AC). Ten healthy subjects were tested. Electrodes were positioned over the midline (Oz, Iz, CBz) and at 3, 6 and 9 cm intervals lateral to the midline electrodes bilaterally.
View Article and Find Full Text PDFWe have recently shown that it is possible to record vestibular cerebellar evoked potentials (VsCEPs) in the form of a contralateral short-latency biphasic positive-negative wave with surface electrodes placed over the posterior fossa and, in parallel with this, the spontaneous electrocerebellogram (or ECeG). VsCEPs were further shown to exhibit considerable plasticity depending on visual context and in this article we show additionally that the ECeG power and cerebro-cerebellar coherence which accompanies the VsCEPs also changes systematically during vestibular and optokinetic stimuli. In a sample of nine healthy human subjects, half of whom had VsCEPs, we recorded in parallel the ECeG and for comparison the EEG from central scalp sites.
View Article and Find Full Text PDFWe recorded evoked potentials (EPs) from over the posterior fossa and in parallel ocular vestibular evoked myogenic potentials (OVEMPs) during visuo-vestibular stimulation in a sample of 7 male and 11 female human subjects. In 9 of the 18 subjects we were able to record EPs reliably in the form of an early biphasic positive-negative wave with latencies ~12 and 17 ms ipsilateral to head acceleration direction (P12-N17) and a slightly later, contralateral, biphasic positive-negative wave with latencies ~19 and 23 ms (P19-N23). The amplitudes of the responses varied widely between subjects.
View Article and Find Full Text PDFThe electrocerebellogram (ECeG), a manifestation of cerebellar cortical local field potentials (LFPs), is characterised by a predominance of high frequency components at the gamma range (30-80 Hz) and beyond up to several hundred Hz, in contrast to the electroencephalogram (EEG) which is composed predominantly of lower frequencies at or below the gamma range. Although the potential clinical role of the ECeG has been suggested, the prospect of a non-invasive method for routine recording in humans has remained elusive. Here we show for the first time that high-frequency power characteristic of the ECeG may be easily measurable using surface electrodes placed over the posterior fossa at the approximate original 10/20 CB location.
View Article and Find Full Text PDFThis study investigated the effect of eye gaze and head position on vestibular-evoked potentials (VsEPs). Head position would be expected to affect myogenic sources, and eye position is known to affect ocular myogenic responses (ocular vestibular-evoked myogenic potentials), whereas a neurogenic source should behave otherwise. Eleven healthy subjects were recruited, and VsEPs, using 72-channel EEG, were recorded at a fixed intensity above the vestibular threshold.
View Article and Find Full Text PDFFront Hum Neurosci
September 2015
Some 20 years ago Todd and colleagues proposed that rhythm perception is mediated by the conjunction of a sensory representation of the auditory input and a motor representation of the body (Todd, 1994a, 1995), and that a sense of motion from sound is mediated by the vestibular system (Todd, 1992a, 1993b). These ideas were developed into a sensory-motor theory of rhythm and beat induction (Todd et al., 1999).
View Article and Find Full Text PDFIn this paper we present a reanalysis of electrophysiological data originally collected to test a sensory-motor theory of beat induction (Todd et al., 2002; Todd and Seiss, 2004; Todd and Lee, 2015). The reanalysis is conducted in the light of more recent findings and in particular the demonstration that auditory evoked potentials contain a vestibular dependency.
View Article and Find Full Text PDFIn this paper I give a brief summary of what is known about the acquisition, use and fate of the radium sources that were in the possession of Lord Rutherford during his lifetime. The account is written in two parts, corresponding to the periods from the discovery of radium in 1898 until his death in 1937 and then from 1937 until recent times. The history of Rutherford's radium closely shadows the history of radioactivity, the evolution of nuclear physics, the race for the bomb, and the development of the nuclear industry.
View Article and Find Full Text PDFWe report the results of a study to record vestibular evoked potentials (VsEPs) of cortical origin produced by impulsive acceleration (IA). In a sample of 12 healthy participants, evoked potentials recorded by 70 channel electroencephalography were obtained by IA stimulation at the nasion and compared with evoked potentials from the same stimulus applied to the forefingers. The nasion stimulation gave rise to a series of positive and negative deflections in the latency range of 26-72 ms, which were dependent on the polarity of the applied IA.
View Article and Find Full Text PDFThe findings are reported of an investigation into rhythmic differences between infant-directed speech (IDS) and adult-directed speech (ADS) in a corpus of utterances from Australian English mothers speaking to their infants and to another adult. Given the importance of rhythmic cues to stress and word-segmentation in English, the investigation focused on the extent to which IDS makes such cues salient. Two methods of analysis were used: one focused on segmental durational properties, using a variety of durational measures; the other focused on the prominence of vocalic/sonorant segments, as determined by their duration, intensity, pitch, and spectral balance, using individual measures as well as composite measures of prominence derived from auditory-model analyses.
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