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Biomedical subjects

F Moss

Publications and source records attributed to F Moss.

At least 19 recordsLinked to original sources
PubMed2003

Stochastic phase synchronization in the crayfish mechanoreceptor/photoreceptor system.

The two light-sensitive neurons in the crayfish's abdominal sixth ganglion ("caudal photoreceptors," or CPRs), are both primary light sensors and secondary neurons in a mechanosensory pathway. Pei et al. (1996) demonstrated that light enhances the transduction of weak, periodic hydrodynamic stimuli (measured as an increase in the signal-to-noise ratio at the stimulus frequency in the power spectrum of the recorded neural spikes). This has been interpreted as a stochastic resonance effect, in which added light increases the noise intensity of the input to the photoreceptor (possibly through fluctuations in membrane potential), leading to an enhancement of the signal-to-noise ratio (SNR). Here, we discuss the recent demonstration (Bahar et al., 2002) of the correlation between a stochastic-resonance-like effect and an increase in stochastic phase synchronization between the neural response and a periodic mechanical stimulus. We also discuss a novel effect (Bahar et al., 2002) in which light increases the SNR of the second higher harmonic of a periodic input signal, effectively rectifying the input signal. This "second harmonic effect" can also be interpreted in terms of stochastic phase synchronization (Bahar et al., 2002). We review other recent results on the role of stochastic phase synchronization in mediating sensory responses in the crayfish nervous system.

Animals↗
PubMed2001

Entropy and local uncertainty of data from sensory neurons.

We present an empirical comparison between neural interspike interval sequences obtained from two different kinds of sensory receptors. Both differ in their internal structure as well as in the strength of correlations and the degree of predictability found in the respective spike trains. As a further tool in this context, we suggest the local uncertainty, assigning a well-defined predictability to individual spikes. The local uncertainty is demonstrated to reveal significant patterns within the interspike interval sequences, even when its overall structure is (almost) random. Our approach is based on the concept of symbolic dynamics and information theory.

Animals↗
PubMed2001

Synchronization of hyperexcitable systems with phase-repulsive coupling.

We study two-dimensional arrays of FitzHugh-Nagumo elements with nearest-neighbor coupling from the viewpoint of synchronization. The elements are diffusively coupled. By varying the diffusion coefficient from positive to negative values, interesting synchronization patterns are observed. The results of the simulations resemble the intracellular oscillation patterns observed in cultured human epileptic astrocytes. Three measures are proposed to determine the degree of synchronization (or coupling) in both the simulated and the experimental system.

Astrocytes↗
PubMed2001

Behavioral stochastic resonance: how a noisy army betrays its outpost.

Juvenile paddlefish prey upon single zooplankton by detecting a weak electric signature resulting from its feeding and swimming motions. Moreover, it has recently been shown that paddlefish make use of stochastic resonance near the threshold for prey detection: a process termed behavioral stochastic resonance. But this process depends upon an external source of electric noise. A swarm of plankton, for example, Daphnia, can provide this noise. Assuming that juvenile paddlefish attack single Daphnia as outliers in the vicinity of the swarm, making use of noise from the swarm, we calculate the spatial distribution of the average phase locking period for the subthreshold signals acting at the paddlefish rostrum. Numeric evaluation of analytic formulas supports the notion of a noise-induced widening of the capture area quantitatively.

Algorithms↗
PubMed2001

Working and learning together: good quality care depends on it, but how can we achieve it?

Educating healthcare professionals is a key issue in the provision of quality healthcare services, and interprofessional education (IPE) has been proposed as a means of meeting this challenge. Evidence that collaborative working can be essential for good clinical outcomes underpins the real need to find out how best to develop a work force that can work together effectively. We identify barriers to mounting successful IPE programmes, report on recent educational initiatives that have aimed to develop collaborative working, and discuss the lessons learned. To develop education strategies that really prepare learners to collaborate we must: agree on the goals of IPE, identify effective methods of delivery, establish what should be learned when, attend to the needs of educators and clinicians regarding their own competence in interprofessional work, and advance our knowledge by robust evaluation using both qualitative and quantitative approaches. We must ensure that our education strategies allow students to recognise, value, and engage with the difference arising from the practice of a range of health professionals. This means tackling some long held assumptions about education and identifying where it fosters norms and attitudes that interfere with collaboration or fails to engender interprofessional knowledge and skill. We need to work together to establish education strategies that enhance collaborative working along with profession specific skills to produce a highly skilled, proactive, and respectful work force focused on providing safe and effective health for patients and communities.

Cooperative Behavior↗
PubMed2001

Informed consent and the preregistration house officer.

A survey of preregistration house officers demonstrated that less than a third had never felt compelled to obtain consent from patients for procedures they themselves did not understand. This had occurred frequently for over a fifth of respondents. Learning how to obtain informed consent is an important part of the education and training of a doctor. The wrong lessons will be learned if they feel compelled to do this when ill-equipped with relevant information about risks and alternatives.

Hospitals, District↗