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Patients suffering from epilepsy commonly experience behavioral symptoms. Behavioral manifestations are especially prevalent in patients with seizures originating in the limbic system. This case report illustrates how an objective, multimodality work-up can guide the clinician in the diagnosis and the treatment of a patient with a complex presentation.After the discontinuation of some medications, the patient underwent a multimodality work-up that consisted of MRI, SPECT, and conventional and quantitative EEG (LORETA). In this case, the functional imaging studies showed a convergence of findings across the three modalities: MRI, SPECT and qEEG. Because of these findings, we supported more aggressive treatment of the seizure disorder. Ultimately this treatment resulted in resolution of the aggression and the depression.In summary, when applied routinely, a comprehensive, systematic, diagnostic approach will minimize treatment false starts and failures, may reduce costs, and also, potentially decrease the severity and the duration of symptoms.

Measured values of mol fraction (X) and δ13C in the Fe(CO3)OH component of 49 samples of goethite (α-FeOOH) from a wide variety of environments range from 0.0015 to 0.0182 and from −21.7 to +3.3‰, respectively. The distribution of δ13C values appears to be bimodal. δ13C values are > −12‰ for marine hydrothermal goethites and continental goethites crystallized as secondary minerals in host rocks. With the exception of a young soil (DRR), δ13C is < −14‰ for pedogenic/oolitic and bog ore goethites.

Hydrogen isotope exchange experiments between goethite and water vapor were performed at 22°C after vacuum “outgassing” at temperatures ranging from 100 to 140°C. The results for five natural and one synthetic goethite can be most simply interpreted in terms of two hydrogen reservoirs in the mineral. One reservoir is stoichiometric, structural hydroxyl hydrogen (FeOOH) which does not seem to exchange at 22°C on the timescales of these experiments. The other reservoir, as indicated by chemical analyses, appears to be nonstoichiometric hydrogen which persists in the sample even after outgassing at 100 to 140°C. This “high temperature” nonstoichiometric (HTN) hydrogen rapidly exchanges isotopes with water vapor at 22°C and seems to have reached, or closely approached, exchange equilibrium after only 15 to 17 hours. The isotopic fractionation factor (αe−v) between the HTN hydrogen and water vapor is estimated to be about 0.996 at 22°C. The exchange experiments indicate that the D/H ratio of stoichiometric hydrogen is not changed by the procedure for outgassing at 100 to 140°C. The amount of HTN hydrogen ranges from nearly zero to about 20% of the total hydrogen among these samples. When present in higher proportions, exchange experiments of the type described here may be necessary to determine the δD value of structural OH in goethite. However, outgassing at about 100°C in vacuum prior to dehydration at 850°C appears to be sufficient for measurement of δD values of structural OH in many natural goethites.

Carbon, as a possibly “indigenous” minor element impurity in goethites, appears to exist in two principal forms: 1.(1) CO2trapped in the mineral structure and2.(2) organic matter. With one exception the total carbon content of the samples in this study ranges between 0.2 and 2.0 weight percent (reported as CO2). Total carbon δ13C values have a range from −27.2 to −8.1 per mil. Values of the mole fraction of trapped CO2in the goethite total carbon as determined for seven samples vary from 0.11 to 0.50. Much of the variation of total carbon δ13C values in these samples can be attributed to different trapped CO2/organic matter ratios in the different goethites. By analogy with speleothems and soil carbonates, δ13C values of trapped CO2could indicate whether the environment of goethite formation was relatively open or closed to mixing with CO2from the Earth's atmosphere.

A distinct relationship exists between the δD values of cellulose carbon bound hydrogen in trees and average annual temperature for a variety of trees from a wide range over North America. The slope of the δD/T relationship is 5.8‰°C−1. Samples of annual precipitation covering much the same geographical range as the trees exhibit a comparable temperature coefficient of 5.6‰°C−1. Such growth-site conditions as poor drainage and/or low relative humidity seem to perturb the spatial δD/T relationship. However, our data indicate that suitable tree growth sites are more the rule than the exception.

Concentrations of the Fe(CO 3)OH component in goethites from Phanerozoic oolitic ironstones appear to record information on the partial pressures of soil CO 2in ancient subaerial weathering environments. Application of a simple steady-state, one-dimensional, Fickian diffusion model to ancient goethite-bearing soils suggests that it may be possible to calculate lower limits for the partial pressure of oxygen in the Earth's atmosphere by using both the inferred soil CO 2partial pressure and estimates of the partial pressure of atmospheric CO 2. Extant data from colitic goethites indicate that the atmospheric PO 2value was no lower than about 13% of the present atmospheric level (PAL) in the Late Ordovician. This value affirms existing evidence for abundant molecular oxygen in the Earth's atmosphere in the Early Paleozoic, i.e., before the widespread advent of vascular plants. Extensive colonization of the continents by vascular plants in the Devonian was associated with calculated atmospheric oxygen partial pressures that were no lower than about 39% of PAL at 360 Ma BP. For Early Jurassic to Late Cretaceous samples, the calculated lower limit of atmospheric oxygen ranged from about 20 to 25% of the present value. It remains to be established whether or not there is a systematic relationship between calculated minimum Po 2values (or soil respiration rates) and the actual partial pressure of atmospheric oxygen.

Abundance and carbon isotope data from an Fe(CO3)OH component in apparent solid solution in oolitic goethites have been used to infer ancient atmospheric CO2 pressures. A test of the validity of these estimates might be comparisons of the carbon isotope compositions of Fe(CO3)OH in oolitic goethites with time-equivalent pedogenic calcites. Temporal trends of the oolitic goethite and pedogenic calcite δ13C values are generally similar, but time-equivalent samples from each of these two groups are not common in the existing data. To facilitate discussion of the concept, comparisons were made of available goethite and calcite samples even though ages of the compared samples in each pair were not identical. In four out of the five comparisons, Fe(CO3)OH abundance and δ13C data were combined with pedogenic calcite δ13C data to calculate physically reasonable soil CO2 concentrations for the ancient calcitic soids. This suggests that the compared oolitic goethite and pedogenic calcite systems were responding to the same global scale phenomenon (i.e., atmospheric CO2). Atmospheric PCO2 as determined from the goethites in these four “well-behaved” cases ranged from values indistinguishable from modern (within analytical uncertainty) to values up to approximately 16 time modern (modern atmospheric PCO2 was taken to be 10−3.5 atm). One interpretation of the fifth, “anomalous”, comparison is that atmospheric CO2 levels increased from about 3 times modern to about 18 times modern from the Triassic into the Early Jurassic. This inferred value for the PCO2 of the Early Jurassic atmosphere is not uniquely constrained by the existing data and needs to be substantiated. However, even considerably lower Early Jurassic atmospheric PCO2 values of 6 to 9 times modern (i.e., 1/3 to 1/2 of the estimated value of 18 times modern) would still indicate significant differences between the global carbon cycles then and now. These results highlight the need for more research on the behavior of the atmosphere during and after the Triassic-Jurassic transition.

1. Neurones in the supraoptic nucleus were examined for their responsiveness to microiontophoretically applied monoamines and cholinomimetic agents. One hundred and sixty‐one of the 749 neurones recorded were antidromically identified as neurosecretory cells.

THERE is considerable evidence of neuromuscular dysfunction in most patients with all types of the functional psychoses. Examples of such dysfunction are (1) increased activity of skeletal-muscle-type creatine phosphokinase (CPK) in serum in the acute stage of psychosis1–4; (2) abnormally large increases in serum CPK activity with a standardised exercise test performed by patients in symptomatic remission5; (3) morphological abnormalities in skeletal muscle fibres at biopsy, particularly scattered atrophic fibres and extensive areas of Z-band streaming6–8; and (4) abnormalities of eye movements in tracking a pendulum9. The skeletal muscle fibre abnormalities found in psychotic patients are likely to be neurogenic in origin10.

α-L-aspartyl-L-alanine, a dipeptide found in the brain, increases the amplitude of the miniature endplate potentials (MEPPs) in phrenic nerve-diaphragm preparations from rats. The peptide also stimulates the appearance of a population of ‘giant’ MEPPs.