Marshall Hall, the reflex arc and epilepsy

Marshall Hall (1790-1857), who graduated from the University of Edinburgh's Medical School in 1812, was considered one of the greatest physiologists of his day. He advanced knowledge in various areas of medicine, in particular elucidating the mechanism of reflex activity in 1833. Hall suggested that convulsive epileptic seizures arose from heightened activity in the afferent limb or the central component of the reflex arc. From 1838 onwards he developed the idea that reflex-mediated neck muscle spasm in seizures obstructed cerebral venous return, congested the brain and thus caused unconsciousness. Associated reflex-mediated laryngeal spasm then caused convulsing. This was the most comprehensive physiologically based explanation of the major features of the convulsive epileptic seizure then available. Hall subsequently advocated and employed tracheotomy to prevent epileptic convulsing. His idea was taken up, modified and made more acceptable by others, and for a generation was the widely acknowledged basis for interpreting epileptogenesis. However, from 1870 onwards it was superseded by John Hughlings Jackson's accumulating evidence that epileptic seizures often arose in the cerebral cortex

Absinthe, epileptic seizures and Valentin Magnan

Absinthe is an alcoholic liquor containing extracts from the wormwood plant. It was widely consumed in France in the late nineteenth century. Its production was banned in 1915, partly because it was thought to cause neurological disturbances, including mental changes and epileptic seizures. Modern knowledge of an acceptable content of the convulsant alpha-thujone in absinthe has allowed the lifting of the production bans, and called into question the experimental work of Valentin Magnan in the 1870s, which formed the scientific background to the campaign against absinthe. An examination of Magnan's published investigations suggests that his science was very adequate by the standards of his time, and that he had shown that an alcohol-soluble component of wormwood did produce lapses of consciousness, myoclonic jerks and tonic-clonic convulsions in animals. Whether that component, presumably thujone, was present at convulsant concentrations in some of the available absinthes of Magnan's time cannot now be known

Hubert Airy, contemporary men of science and the migraine aura

Although there had been occasional references to the visual aura of migraine even in ancient medicine, little attention was given to the phenomenon until the first half of the nineteenth century when French authors began to describe it. In the medicine of English-speaking countries, apart from a few descriptions, it went largely unnoticed until the British Astronomer Royal, Sir George Airy, described his own experience of the visual aura in 1865. Five years later his son, Hubert Airy, also described his experience of it and that of a number of eminent contemporary men of science. The topic of the migraine aura was almost immediately taken up by two of the younger Airy's contemporaries and fellow Cambridge medical graduates, Peter Wallrock Latham and Edward Liveing, in their monographs. Subsequently, migraine with aura quickly became a well-recognised clinical entity in British medicine

Comparisons Among Parent Reports and Self-Reports of Sleep in ADHD and Normal School-Aged Children

The objective of the study was to investigate whether school-aged children diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD) experience greater sleep disturbance than do normally-developing children. Participants included 33 parents and their children with ADHD (mean age = 10.7 ± 1.7 years) and 33 parents and their children without ADHD (mean age = 10.7 ± 1.6 years). Both parents and their children completed sleep questionnaires developed to assess a number of sleep variables. Based on parental report, the Total Sleep Disturbance score was significantly greater for the ADHD group than for the comparison group. Parents indicated that children with ADHD had significantly more disturbed sleep than did children without ADHD on 8 of the 10 sleep subscales of the Sleep Questionnaire for Parents. These were: Bedtime Resistance, Morning Difficulty, Parasomnias/Other Sleep Disturbance, Restless Legs Syndrome, Sleep Anxiety/Transitioning, Sleep Duration/Quality, Sleep Hygiene, and Sleep Onset. Although bedtimes and morning wake times were similar for children with ADHD and children in the comparison group, parents reported that children with ADHD experienced significantly less total time asleep. The children with ADHD reported their own sleep to be significantly more problematic than did the children in the comparison group. Similar to the parents\u27 reports, children\u27s reports of Total Sleep Disturbance was greater for the ADHD group than for the comparison group. Six of the 8 subscales on the Sleep Questionnaire for Children indicated more disturbed sleep for the children with ADHD: Bedtime Resistance, Daytime Sleepiness, Morning Difficulty, Sleep Anxiety/Transitioning, Sleep Duration/Quality, and Sleep Onset. These findings suggest that sleep disturbance should be routinely assessed as part of the clinical evaluation for and treatment of ADHD

Where's the harm? A social marketing approach to reframing 'problem' drinking cultures

Alcohol consumption is often linked to a broad range of social and health problems, yet alcohol also plays a fundamental role in social bonding between people. This paper considers the potential of social marketing to contribute to alcohol consumption reduction and reframe social norms that encourage 'problem' drinking. Based on qualitative research with a variety of Scottish drinkers, the paper emphasises how and why a better understanding of the culturally bound meanings of alcohol (e.g. social identity, self-concept) are of crucial importance to inform any social marketing approach to reframing excessive drinking

A proposal for a different chi-square function for Poisson distributions

We obtain an approximate Gaussian distribution from a Poisson distribution after doing a change of variable. A new chi-square function is obtained which can be used for parameter estimations and goodness-of-fit testing when adjusting curves to histograms. Since the new distribution is approximately Gaussian we can use it even when the bin contents are small. The corresponding chi-square function can be used for curve fitting. This chi-square function is simple to implement and presents a fast convergence of the parameters to the correct value, especially for the parameters associated with the width of the fitted curve. We present a Monte Carlo comparative study of the fitting method introduced here and two other methods for three types of curves: Gaussian, Breit-Wigner and Moyal, when each bin content obeys a Poisson distribution. It is also shown that the new method and the other two converge to the same result when the number of events increasesComment: 27 pages, 13 figure

Statistical uncertainty in quantum optical photodetection measurements

We present a complete statistical analysis of quantum optical measurement schemes based on photodetection. Statistical distributions of quantum observables determined from a finite number of experimental runs are characterized with the help of the generating function, which we derive using the exact statistical description of raw experimental outcomes. We use the developed formalism to point out that the statistical uncertainty results in substantial limitations of the determined information on the quantum state: though a family of observables characterizing the quantum state can be safely evaluated from experimental data, its further use to obtain the expectation value of some operators generates exploding statistical errors. These issues are discussed using the example of phase-insensitive measurements of a single light mode. We study reconstruction of the photon number distribution from photon counting and random phase homodyne detection. We show that utilization of the reconstructed distribution to evaluate a simple well-behaved observable, namely the parity operator, encounters difficulties due to accumulation of statistical errors. As the parity operator yields the Wigner function at the phase space origin, this example also demonstrates that transformation between various experimentally determined representations of the quantum state is a quite delicate matter.Comment: 18 pages REVTeX, 7 figures included using epsf. Few minor corrections made, clarified conclusion

Globular Cluster Systems in Brightest Cluster Galaxies. III: Beyond Bimodality

We present new deep photometry of the rich globular cluster (GC) systems around the Brightest Cluster Galaxies UGC 9799 (Abell 2052) and UGC 10143 (Abell 2147), obtained with the HST ACS and WFC3 cameras. For comparison, we also present new reductions of similar HST/ACS data for the Coma supergiants NGC 4874 and 4889. All four of these galaxies have huge cluster populations (to the radial limits of our data, comprising from 12000 to 23000 clusters per galaxy). The metallicity distribution functions (MDFs) of the GCs can still be matched by a bimodal-Gaussian form where the metal-rich and metal-poor modes are separated by ~0.8 dex, but the internal dispersions of each mode are so large that the total MDF becomes very broad and nearly continuous from [Fe/H] = -2.4 to Solar. There are, however, significant differences between galaxies in the relative numbers of \emph{metal-rich} clusters, suggesting that they underwent significantly different histories of mergers with massive, gas-rich halos. Lastly, the proportion of metal-poor GCs rises especially rapidly outside projected radii R > 4 R_eff, suggesting the importance of accreted dwarf satellites in the outer halo. Comprehensive models for the formation of GCs as part of the hierarchical formation of their parent galaxies will be needed to trace the systematic change in structure of the MDF with galaxy mass, from the distinctly bimodal form in smaller galaxies up to the broad continuum that we see in the very largest systems.Comment: In press for Astrophysical Journa