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Abstract: In this paper, I shall illustrate the personality of Rita Levi-Montalcini and highlight how she first emerged within a prestigious school, while under the direction of Giuseppe Levi, a most inspiring and stimulating figure. Between 1919 and 1938, he created a rich environment capable of influencing the minds of innumerable students; among them, three future Nobel Prize winners, Renato Dulbecco, Salvador Luria, and Rita Levi-Montalcini, who were companions in the same classroom. In 1938, due to the racial laws for the defence of the race, Luria and Levi-Montalcini were banned from entering the university premises. In a small working space in her bedroom—“a minuscule laboratory not unlike a convent cell”—Levi-Montalcini, supported by Levi, made a most outstanding discovery that opened a new chapter in neurobiology. Further collaborations with Viktor Hamburger and Stanley Cohen led Levi-Montalcini to the discovery of the nerve growth factor (NGF): a remarkable accomplishment which turned out to represent a milestone in the development of modern cell biology.Graphical abstract: [ABSTRACT FROM AUTHOR]

Great attention has been given so far to cerebellar control of posture and of skilled movements despite the well-demonstrated interconnections between the cerebellum and the autonomic nervous system. Here is a review of the link between these two structures and a report on the recently acquired evidence for its involvement in the world of emotions. In rodents, the reversible inactivation of the vermis during the consolidation or the reconsolidation period hampers the retention of the fear memory trace. In this region, there is a long-term potentiation of both the excitatory synapses between the parallel fibres and the Purkinje cells and of the feed-forward inhibition mediated by molecular layer interneurons. This concomitant potentiation ensures the temporal fidelity of the system. Additional contacts between mossy fibre terminals and Golgi cells provide morphological evidence of the potentiation of another feed-forward inhibition in the granular layer. Imaging experiments show that also in humans the cerebellum is activated during mental recall of emotional personal episodes and during learning of a conditioned or unconditioned association involving emotions. The vermis participates in fear learning and memory mechanisms related to the expression of autonomic and motor responses of emotions. In humans, the cerebellar hemispheres are also involved at a higher emotional level. The importance of these findings is evident when considering the cerebellar malfunctioning in psychiatric diseases like autism and schizophrenia which are characterized behaviourally by emotion processing impairments. [ABSTRACT FROM AUTHOR]

Preimplantation culture of mouse embryos has been suggested to result in reduced anxiety-like behavior in adulthood. Here, we investigated the effects of in vitro fertilization (IVF), embryo culture, and different diets on anxiety-like behavior using the elevated plus maze (EPM). We hypothesized that exposure to suboptimal conditions during the preimplantation stage would interact with the suboptimal diet to alter behavior. The expression of genes related to anxiety was then assessed by quantitative real-time polymerase chain reaction in various brain regions. When fed a normal diet during gestation and a moderately high-fat Western diet (WD) postnatally, naturally conceived (NC) and IVF mice showed similar anxiety-like behavior on the EPM. However, when fed a low-protein diet prenatally and a high-fat diet postnatally (LP/HF), NC mice showed a modest increase in anxiety-like behavior, whereas IVF mice showed the opposite: a strongly reduced anxiety-like behavior on the EPM. The robust reduction in anxiety-like behavior in IVF males fed the LP/HF diets was, intriguingly, associated with reduced expression of MAO-A, CRFR2, and GABA markers in the hypothalamus and cortex. These findings are discussed in relation to the developmental origin of health and disease hypothesis and the 2-hit model, which suggests that 2 events, occurring at different times in development, can act synergistically with long-term consequences observed during adulthood. [ABSTRACT FROM PUBLISHER]

Intramyocardial fat can be observed in different pathologic processes including arrhythmogenic right ventricular cardiomyopathy (ARVC) and in old myocardial infarction (OMI) In SSFP images, fat is hyperintense and surrounded by a black boundary, called 'Indian Ink' artifact that is generated when fat and water coexist in the same voxel. Aim of this study was to compare the SSFP with the conventional FSE and STIR (FSE/STIR) method for the detection of LV intramyocardial fat. Fifty-four consecutive patients with OMI (>1,000 days) and 69 patients with a diagnosis of ARVC underwent magnetic resonance. LV fat was detected in 29 patients (53.7%) in SSFP images and in 28 patients (51.9%) in FSE/STIR images. At Bland- Altman plot a close agreement was found between the extent of fat measured in SSFP images and in FSE images. However, a slight systematic overestimation, was found for the fat quantification in the SSFP images. In the ARVC group, both FSE/STIR and SSFP images evidenced fat infiltration in LV myocardium in 11 patients (15.9%) without any mismatch. SSFP had 100% sensitivity and 98.8% of specificity to detect LV intramyocardial fat in ARVC and in ischemic heart disease. SSFP sequence with TR/TE = 2 is capable in identifying and quantifying the presence of fat tissue within the LV myocardium in patients with previous myocardial infarction and ARVC. [ABSTRACT FROM AUTHOR]

In the adult brain, new synapses are formed and pre-existing ones are lost, but the function of this structural plasticity has remained unclear. Learning of new skills is correlated with formation of new synapses. These may directly encode new memories, but they may also have more general roles in memory encoding and retrieval processes. Here we investigated how mossy fibre terminal complexes at the entry of hippocampal and cerebellar circuits rearrange upon learning in mice, and what is the functional role of the rearrangements. We show that one-trial and incremental learning lead to robust, circuit-specific, long-lasting and reversible increases in the numbers of filopodial synapses onto fast-spiking interneurons that trigger feedforward inhibition. The increase in feedforward inhibition connectivity involved a majority of the presynaptic terminals, restricted the numbers of c-Fos-expressing postsynaptic neurons at memory retrieval, and correlated temporally with the quality of the memory. We then show that for contextual fear conditioning and Morris water maze learning, increased feedforward inhibition connectivity by hippocampal mossy fibres has a critical role for the precision of the memory and the learned behaviour. In the absence of mossy fibre long-term potentiation in Rab3a−/− mice, c-Fos ensemble reorganization and feedforward inhibition growth were both absent in CA3 upon learning, and the memory was imprecise. By contrast, in the absence of adducin 2 (Add2; also known as β-adducin) c-Fos reorganization was normal, but feedforward inhibition growth was abolished. In parallel, c-Fos ensembles in CA3 were greatly enlarged, and the memory was imprecise. Feedforward inhibition growth and memory precision were both rescued by re-expression of Add2 specifically in hippocampal mossy fibres. These results establish a causal relationship between learning-related increases in the numbers of defined synapses and the precision of learning and memory in the adult. The results further relate plasticity and feedforward inhibition growth at hippocampal mossy fibres to the precision of hippocampus-dependent memories. [ABSTRACT FROM AUTHOR]

Copyright of Rendiconti Lincei: Scienze Fisiche e Naturali is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract??Congenital ventricular diverticulum is a rare cardiac abnormality, frequently associated with other cardiac or non-cardiac congenital malformations. Clinically, congenital ventricular diverticulum may be asymptomatic or cause systemic embolization, heart failure, ventricular rupture, ventricular arrhythmia and sudden death. Cardiac magnetic resonance (CMR) can be a useful non-invasive and non-ionizing method to confirm the presence, size and extent of left ventricular (LV) diverticulum and its tissue characterization. In these reports we documented the presence of six diverticuli in patients underwent to CMR for other clinical indications. In all the cases, magnetic resonance showed an accurate assessment of diverticuli. [ABSTRACT FROM AUTHOR]

With an ever-increasing understanding of the brain mechanisms associated with core human attributes and values, there is an increasing public interest in the results of neuroscience research and the ways in which that new knowledge will be used. Here, we present perspectives on engaging the public on these issues on an international scale, the role of the media, and prospects for the new field of neuroethics as both a focus and a driver of these efforts. [ABSTRACT FROM AUTHOR]

With an ever-increasing understanding of the brain mechanisms associated with core human attributes and values, there is an increasing public interest in the results of neuroscience research and the ways in which that new knowledge will be used. Here, we present perspectives on engaging the public on these issues on an international scale, the role of the media, and prospects for the new field of neuroethics as both a focus and a driver of these efforts. [ABSTRACT FROM AUTHOR]

The paper describes the study carried out on a sample of 27 coronary artery disease patients, aiming to determine a correlation between coronary artery disease and anomalies in the retinal circulation. Patients underwent selective coronary arteriography and fundus fluorescein angiography that allowed us to investigate the dye dynamics and to detect abnormalities of time evolution, vessel walls, and flux. During the fluorescein angiography we measured time events as the choroidal flush (ta) the start of the laminar phase (tb), and the end of the laminar phase (tc) and we took pictures that were digitally processed in order to compute the ROI1/ROI2 value, assumed as a numerical index of ischemia of the optic disc. In the examined sample we found ta=61±109, tb=65±107, tc=159±155, and ROI1/ROI2=0.968±0.300. Normal ranges for these parameters were determined by the fundus fluorescein angiography of a control group of 10 patients, unaffected by coronary artery disease and ischemic pathology of the retinal network; we found ta=12±4, tb=16±8.5, tc=44±9.3, and ROI1/ROI2=0.735±0.086. Eighty-five percent of coronaropatic patients showed ischemia of the optic disc, 89% anomalies of the epi-peripapillar network, 70% anomalies of the papillo-macular network, and 89% evidence of at least two findings of ischemia; 85% of patients showed a value of ROI1/ROI2 out of the normal range. The unpaired Student's t-test between the coronaropatic and the control group does not show significant differences between ta and tb; on the contrary, those with coronary disease and the control group were statistically different for tc ( p≤0.02). Moreover, we have found a correlation between the numerical index of optic disc ischemia and the severity of coronary artery disease (r=0.68, p≤0.01). Hence, the vascular abnormalities shown by the fluorescein angiography can constitute valid noninvasive markers and can advise further cardiological tests for a coronary artery disease not yet diagnosed. [ABSTRACT FROM AUTHOR]

While sustained retinal slip is assumed to be the basic conditioning stimulus in adaptive modifications of the vestibulo-ocular reflex (VOR) gain, several observations suggest that eye motion-related signals might also be involved. We oscillated pigmented rats over periods of 20 min around the vertical axis, at 0.3 Hz and 20°/s peak velocity, in different retinal slip and/or eye motion conditions in order to modify their VOR gain. The positions of both eyes were recorded by means of a phase-detection coil system with the head restrained. The main findings came from the comparison of two basic conditions - including their respective controls - in which one or both eyes were reversibly immobilised by threads sutured to the eyes. In the first condition the animals were rotated in the light with one eye immobilised and the other eye free to move but covered. Rotation in the light in this open-loop condition immediately elicited high-gain compensatory eye movements of the non-impeded, covered eye. At the end of this training procedure, the VOR gain increased by 42.3%. In the second condition, both eyes were immobilised and one eye was covered. The result was an increase in the VOR gain of 26.3%. These two conditions were similar as to the visuo-vestibular drive during the exposure, but different as to the resulting - and allowed - eye motion, showing that the condition where the larger eye movements occurred yielded the larger VOR gain change. Our data support the idea proposed by Collewijn and Grootendorst (1979, p. 779) and Collewijn (1981, p. 146) that '[retinal] slip and eye movements seem to be relevant signals for the adaptation of the rabbit's visuo-vestibular oculomotor reflexes'. Our data also suggest that sensory information related to eye movements, more likely than efference copy, is the coding signal for eye movement which combines with the retinal slip signal to generate adaptive changes of the VOR. [ABSTRACT FROM AUTHOR]

The gain of the vestibulo-ocular reflex (VOR) of intact pigmented rats was adaptively modified by training protocols that created a visual-vestibular conflict. For training, head restrained animals were oscillated on a turntable in front of an optokinetic pattern projected onto a cylindrical wall. The optokinetic pattern either moved the same amplitude with the animal ('in-phase': 0.05 Hz ± 20°/s) or opposite in direction ('out-of-phase': turntable and pattern 0.05 Hz ± 10°/s each). VOR responses were tested in darkness before and after each 8 min training period for a duration of 40 min. During 'out-of-phase' training the gain of compensatory eye movements measured in light was close to 2 from the beginning on and the VOR tested in darkness increased in gain progressively from 0.48 (±0.12) to 0.9 (±0.3; P < 0.05) in 5 out of 7 rats. Two rats did not adapt their VOR gain. Phase values decreased slightly by about 10°. During 'in-phase' stimulation compensatory eye movements were almost completely suppressed (gain close to 0) from the beginning on and the VOR tested in darkness decreased gradually in gain from 0.62 (±0.17) to 0.13 (±0.1; P<0.001) in all 6 trained rats. Phase values decreased in parallel from 151° to 119° ( P< 0.01). The effectiveness of the 'in-phase' training paradigm in the absence of compensatory eye movements indicates that retinal image slip is the relevant signal for adaptation. In seven rats with histologically verified almost complete inferior olive (IO) lesions (chemically induced at least 45 days prior to training), 'out-of-phase' and 'in-phase' stimulation evoked compensatory eye movements with gains comparable to those in intact rats. VOR parameters measured in darkness were altered with respect to those of control rats. Gain differed extremely between individuals and phase lag re acceleration was in all IO-lesioned rats larger than in intact rats. The time constant of the VOR in response to table velocity steps was significantly longer (17 s ±4) than in intact rats (11 s ± 3). Training did not alter the gain of the VOR in 5 out of 7 IO-lesioned rats. One rat increased its gain during 'out-of-phase' training in the first, but not during a second training session (and not during 'in-phase' training) and another rat decreased its gain during 'in-phase' training (but not during 'out-of-phase' training). These changes in VOR gain might have occurred by chance rather than by learning. The absence of adaptation in IO-lesioned rats can be explained either by the absence of climbing fiber mediated slip signals in the cerebellar cortex or by lesion-induced secondary changes which result in a long-term reduction of the inhibitory efficacy of Purkinje-cells. In the absence of arousing stimuli VOR responses of intact rats exhibit a strong decrement during table oscillations in darkness. Between trials, with the rat at rest, response magnitude recovered spontaneously. Six out of 8 IO-lesioned rats expressed a very similar modification of their VOR gain. These results indicate that the neural mechanisms responsible for adaptive gain decrease during 'in-phase' training and those responsible for a gain decrease during short-term habituation are different. [ABSTRACT FROM AUTHOR]

The present study was aimed at investigating the alterations of the spontaneous saccadic eye movements of pigmented rats following ethanol administration. In addition we have studied the efficacy of the imidazobenzodiazepine Ro 15-4513 in reversing the effects of alcohol on saccades. The horizontal component of spontaneous eye movements was recorded by means of the magnetic field search coil technique on 11 head-restrained, pigmented rats. After the intraperitoneal injection of ethanol (1 g/kg) spontaneous saccades showed: i) a backward post-saccadic drift, with an exponentiallike time course (time constant 100-150 ms); ii) a remarkable reduction of mean saccadic amplitude, up to 37% of control; iii) a significant decrease of peak velocity, which was reduced to about 80% of control. All these effects appeared and developed within a few minutes after the administration and were still present one hour later. When Ro 15-4513 (5 mg/kg) was injected i.p., 15 min after ethanol, the post-saccadic drift amplitude was immediately reduced and the drift was completely abolished within about 30 min. Mean saccadic amplitude returned to control values within a few minutes and was then steadily maintained for the following period examined (30 min). On the contrary, peak velocity showed only a slight tendency to recover which never was significant. When the same dose of Ro 15-4513 was injected alone there was no post-saccadic drift. However, mean saccadic amplitude increased, almost immediately, up to 160% of control. Its value showed a slight constant decrease in the following 30 min. Peak velocity was only slightly increased (up to 106% of control), but never was significantly different from control. Our results show that ethanol induces a remarkable impairment in the performance of spontaneous saccades. The imidazobenzodiazepine Ro 15-4513 is able to reverse completely only some of the alcohol-induced alterations, i.e. the posts-accadic drift and the reduction of saccadic amplitude, while it fails to counter efficiently the reduction of peak velocity. Ro 15-4513 exerts an intrinsic action, which is opposite to that of ethanol, on some of the saccadic parameters we have examined. [ABSTRACT FROM AUTHOR]

Unitary climbing fibre activity has been systematically recorded in the rabbit cerebellar cortex at the level of the Purkinje cell layer every 100 μm along the longitudinal axis of the folium. In one group of animals, spontaneous activity was identified in 197 out of 204 (96.6%) explored layers, and was uninterruptedly present up to 2,400 μm along the folia. In a second group of animals, stimulating electrodes were placed in the inferior olive and it was found that spontaneous or evoked climbing fibre activity was absent in only 19 out of 422 explored layers: 377 (89.3%) showed a spontaneous and 396 (93.8%) a short latency evoked activity. If some limitations of the method are considered, it can be concluded that all Purkinje cells receive climbing fibre innervation from cells of the inferior olive. The present experiments support the conclusion that the inferior olive is the unique source of climbing fibres. [ABSTRACT FROM AUTHOR]

In intact and decerebrate pigeon, both under barbiturate anaesthesia, the spontaneous activity of single Purkinje cells has been analysed. The average frequency of the simple spikes was similar to that described in mammals and was essentially the same in the intact and decerebrate preparations. The average frequency of the complex spikes was higher than that found in mammals and it was significantly depressed in the decerebrate pigeon as compared with the intact one. The amount of the depression, however, was less than that described in mammals. For the simple spikes a correlation was found between the mean interspike interval and both the standard deviation and the percentage of intervals at the mode. The correlation indicates that as the frequency increases the firing tends to become more regular. The same conclusion applies to the complex spikes, although in this case the only significant correlation was between the mean interval and standard deviation. Interval histograms of simple spikes were usually unimodal, but were occasionally also bimodal in both intact and decerebrate pigeons. Interval histograms of complex spikes were usually multimodal with many peaks at regular intervals, the highest peak not necessarily being the first one. The duration of the basic interval varied in different cells from 65 to 130 ms. The probability of firing of the simple spikes is always reduced following the appearance of a complex spike. The duration of the pause is related to the frequency of the simple spikes; the higher the frequency, the shorter the pause. [ABSTRACT FROM AUTHOR]

In Wistar rats we have studied the effect of inferior olive lesion or activation on the threshold of a flexor reflex elicited by a nociceptive stimulus applied to the hindpaw. When the inferior olive is lesioned by means of 3-acetylpyridine, the threshold value is significantly decreased. A recovery occurs in 3-4 weeks. When the inferior olive is activated by means of harmaline, the threshold value is significantly increased. These experiments suggest the inferior olive activity exerts an inhibitory effect on flexor reflex activity. The recovery of the threshold value depends, probably, on the plastic reorganization of the cerebellar circuits, which occurs after inferior olive lesion. [ABSTRACT FROM AUTHOR]

Metabolic activity of the intracerebellar nuclei during cryoinactivation of the inferior olive was studied in the anaesthetized rat by using the C-2-deoxyglucose method. Single unit recording of Purkinje cells was simultaneously monitored in the cerebellar cortex. Local inactivation in the inferior olive resulted in regional suppression of complex spike discharges in the cerebellar cortex. An increased metabolic activity was observed in the cerebellar nuclei contralateral to the cryoinactivation site correlating the somatotopically arranged olivo-cerebello-nuclear circuit. This increase was shown to be due specifically to inactivation of the inferior olive, since it was not obtained in a rat in which the inferior olive was previously destroyed by neurotoxic doses of 3-acetylpyridine. The results are interpreted as being due to an increased presynaptic activity of the terminals of the Purkinje cells which fire simple spikes at high rates after climbing fibre deafferentation. [ABSTRACT FROM AUTHOR]

Following an almost total chemical lesion of the inferior olive, the inhibitory control of the cerebellar Purkinje cells upon their target neurones, mainly in Deiters nucleus, remains practically unchanged. This result is at variance with some recent findings having important implications in the cerebellar theories of motor learning. [ABSTRACT FROM AUTHOR]

Iodide-induced hypothyroidism has been observed in subjects treated with compounds with mild antithyroid activity. The hypoglycemic agent tolbutamide belongs to the aminoheterocyclic group, a class of compounds with antithyroid effect. Thus it was thought interesting to study the effect of large doses of iodide on thyroid function in diabetics chronically treated with tolbutamide. Basal thyroid function as assessed by clinical examination and iodothyronine and TSH concentrations was normal in all patients. Furthermore, in diabetics treated with tolbutamide, hormone concentrations were not different from those of patients treated with insulin or diet. Serum T4, T3 and TSH did not show any significant variation throughout the investigation period. Our results suggest that thyroid function is not affected by chronic treatment with tolbutamide even when large doses of iodide are administered. [ABSTRACT FROM AUTHOR]

In the intact, unanesthetized, freely-moving cat the Purkinje cell activity driven by the mossy fiber system presents phasic increases in coincidence with movements of wakefulness or desynchronized sleep. Its rate of discharge may range between wide limits. In contrast, activity driven by the climbing fiber system varies between much more restricted limits. In the absence of movements its rate of dischange is higher during the desynchronized stage of sleep as compared to the synchronized one. In coincidence with the phasic events of paradoxical sleep the rate of discharge presents often a decrease. Some units, which have been assumed to be mossy and climbing fiber afferents, have a behavior similar to the mossy and climbing fiber driven activity, cespectively. Some characteristics of olivo-cerebellar neurons have been presented. A possible role of the mossy fiber and climbing fiber systems, respectively for phasic and tonic functions, is discussed. The pattern of activity during sleep is discussed in relation to the pattern observed in other brain areas. It is suggested that the cerebellum contributes to the collapse of the postural tonus which occurs during paradoxical sleep. [ABSTRACT FROM AUTHOR]

Caloric and galvanic stimulation of the labyrinth can modulate the activity of the Purkinje cells of the cerebellum through both mossy fibre and climbing fibre systems. The former system is modulated in a higher frequency range than the latter. These results were obtained mainly in the vestibular area, but they were also present in other areas of the cerebellum. [ABSTRACT FROM AUTHOR]

In precollicular decerebrate cats, limb nerves have been stimulated and field potentials and unitary activity recorded from the cerebellar cortex. Doses of pentothal up to 8 mg/kg affect neither the activity evoked in the fast mossy fibre pathways, nor the size of the postsynaptic potentials in granule cells, but the axon discharge in these latter cells is clearly affected. With 4-8 mg/kg the axon discharge of granule cells is abolished and as a consequence Purkinje cells do not respond to the peripheral stimulation via the mossy fibres. In contrast the activity evoked through the climbing fibres is enhanced. This effect takes place at precerebellar level. Both the effects on the mossy fibre and climbing fibre pathways show a recovery in 15-60 min depending on the dose. [ABSTRACT FROM AUTHOR]

In cats without general anaesthesia electric stimulation of the optic chiasma evoked usually in the depth of the cerebellar cortex of lobuli VI and VII a sequence of waves at a latency of 7-10 msec which have been shown to be due to the mossy fibre input. A later wave at a latency of 18-20 msec was also sometimes found in isolation or in association with the early wave. This later field has been identified as due to the climbing fibre input. Unitary recordings have given support to this interpretation. Some correlation has been made with recordings obtained by electric stimulation of the superior colliculus and by flash stimulation of the retinae. It is concluded that the optic pathways project to the visual area of the cerebellar cortex through both mossy and climbing fibre inputs, although from this study based mainly on the laminar analysis of evoked fields, the former input seems to be more widespread and more consistently obtained than the latter. [ABSTRACT FROM AUTHOR]

Stimulation of the parallel fibres, or the mossy fibres, in the cerebellar cortex depresses the potential generated in the granular layer by anti-dromic invasion of the Purkinje cells (N), and that generated by the axon discharge of granule cells (P). The reduction of these potentials indicate inhibitions mediated respectively by basket and Golgi cells. The depressions of both N and P potentials are unaffected by strychnine at doses of up to 1 mg/kg. Picrotoxin and bicuculline reduce or suppress both inhibitions at doses of 2 to 5 mg/kg and 0.2 to 0.4 mg/kg respectively. The action of the picrotoxin is long lasting or even possibly irreversible, whereas that of bicuculline lasts only a few minutes. The ratio by weight between the dose of picrotoxin and that of bicuculline necessary to reduce the N and P depression exceeds 10. These results indicate that gamma-aminobutyric acid may be the chemical inhibitory transmitter at basket cell - Purkinje cell and Golgi cell - granule cell synapses. [ABSTRACT FROM AUTHOR]

In decerebrate cats, caloric and galvanic stimulations of the labyrinth were able to modulate the activity of the Purkinje cells through both the afferents which terminate in the cerebellar cortex as mossy fibres and climbing fibres. In response to these stimulations, several patterns of response were seen. For the galvanic stimulation a predominant pattern was described. In most cases the mossy fibre driven activity had an effect which was opposite to that of the climbing fibre one. The climbing fibre driven activity could be modulated only in the low frequency range, but it can interfere remarkably with the mossy fibre one. The results described were obtained not only in the so-called vestibular area of the cerebellum, but also in other areas. [ABSTRACT FROM AUTHOR]

Stimulation of forelimb and hindlimb areas of the sensorimotor cortex in the cat evokes in the lobus anterior of the cerebellum an early response at latency of 3-3.5 msec due to the mossy fibre input (MF) and a later response at latency of 13-16 msec due to the climbing fibre (CF) input. In the pars intermedia these two types of responses are organized in a somatotopic manner: the hindlimb area projects in lobuli HIV and HIII whereas the forelimb area projects to lobulus HV. In the vermis a somatotopic arrangement is less clear. Both forelimb and hindlimb areas of the sensorimotor cortex project to lobuli III, IV and V: on a maintained somatotopy in a caudo-rostral direction there is a tendency for the hindlimb area of the sensorimotor cortex to be well represented in a longitudinal strip close to the paravermal sulcus. This arrangement in the vermis is evident for the CF pathways, but more difficult to demonstrate for the MF pathways. The forelimb area of the sensorimotor cortex projects to those areas of the lobus anterior impinged upon by the forelimb nerves through both the MF and CF systems and the same holds true for the hindlimb area and the hindlimb nerves. [ABSTRACT FROM AUTHOR]

Responses were evoked in the anterior lobe of the cerebellum by volleys in group I and II fibers of forelimb and hindlimb nerves - cutaneous, muscular, joint and fascial. These responses have been observed along microelectrode tracks that traverse the whole depth of the anterior lobe. These tracks have been identified in histological sections, and the recording sites along these tracks have been determined. It has been shown that there are many distinguishing features for the responses produced by the two types of afferent input to the cerebellum: climbing fibers and mossy fibers. The depth profiles are of particular importance in the differentiation of the CF and MF responses, and they correspond to those already determined for the exposed surface areas of the cerebellar cortex. As would be expected from the distribution of synapses by the CF fibers to the Purkinje cell dendrites, there is a maximum extracellular negativity deep in the molecular layer with sources superficial and deep thereto. In contrast, the mossy fiber input produces a powerful synaptic excitation in the granular layer, which is recorded there as a negative wave (N). The mossy fiber input by sequential relay also produces a negative wave (N) in the molecular layer. This wave is distinguished from the CF-evoked negative wave because it is not reversed in the fissura and the adjacent superficial molecular layer. An important distinguishing feature of the MF- and CF-evoked responses is that the latencies of the former are shorter by 6-12 msec for forelimb nerves and by 9-15 msec for hindlimb nerves. It is thus possible to measure the sizes of the MF and CF responses in the same traces. Another distinguishing feature is the failure of the CF responses with stimulus frequencies of 5-15/sec, whereas the MF-evoked potentials are well maintained above 15/sec. Also CF-evoked responses show much more size and latency variance than the MF-evoked responses, and often the facilitation of two or three volleys is required in order to evoke a stable CF response. By utilizing these various tests it is always possible to distinguish between the CF- and the MF-evoked responses recorded along the microelectrode tracks in the anterior lobe. [ABSTRACT FROM AUTHOR]

Volleys in group I and II fibers of muscle nerves and group II fibers of cutaneous, joint and fascial nerves have evoked CF responses in the anterior lobe of the cerebellum. In the pars intermedia there is a fairly sharp somatotopic localization of the forelimb CF responses to the Vth lobule (Larsell) and the hindlimb to the IVth and IIIrd lobules. In the vermis there is much more admixture, with the hindlimb-evoked responses tending to dominate in the lateral vermis of the Vth lobule, and the forelimb more medially. In the IVth and IIIrd lobules forelimb responses were rare and were never large. In the medial vermis up to 1-1.7 mm from the midline there were no CF-evoked responses from the limb nerves. These distributions of CF-evoked responses are remarkably different from those reported by Oscarsson, and consideration is given to the factors responsible for this discrepancy. A more detailed examination was made of the CF-evoked responses from a large variety of hindlimb and forelimb nerves. Observations were made along many tracks usually arranged in a transverse plane, and it was found that between different recording sites along the same track or along adjacent tracks, there was a great deal of variation in the relative magnitudes of the CF-evoked responses from the different nerves. These distributions have an ill-defined patchy character so that at any focus there is opportunity for the most diverse kinds of piecemeal integration. These findings on the CF-input are considered in relationship to the mossy fiber input. It is pointed out that the pathways conveying CF-input to the cerebellum have a level of discriminative input adequate for the operation of fine control. [ABSTRACT FROM AUTHOR]

Copyright of Acta Diabetologica Latina is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Editorial. Discusses the dendritic spines of Purkinje cells in the cerebellar cortex. Factors that control spinogenesis in neurons; Inhibitory action of climbing fibers on spine formation; Total number of spines in the proximal dendrites of rat cerebellum; Implications on the understanding of mechanisms responsible for information transmission and synaptic plasticity.

A letter to the editor is presented in response to the article "Neuronal circuits for fear and anxiety" by P. Tovote, J. P. Fadok, and A. Lüthi in the 2015 issue.

Purpose: Surprisingly, an important characteristic of astigmatism has been overlooked by ophthalmic and clinical scientists. Apparently, refractive astigmatism is due largely to a form of high spatial frequency image distortion. Methods: Characteristic astigmatic image distortion can be minimized or eliminated by using a low-pass spatial filter (here, a ground glass plate was employed for this purpose). The ground glass is placed a short distance in front of a visual acuity chart, or it may be used with other tests, such as vernier acuity. Results: This test has been performed by us on large numbers of patients and test subjects. A clinician can try this test for himself/herself. Place a +2.00 D.C. (any axis) lens in front of the eye; the usual distortions will be observed. Locate the ground glass plate as described. The usual distortions associated with the conoid of Stürm will not be visible or will be virtually eliminated, although some image blur will remain. Conclusions: This technique has significance, e.g., in visual screening programs in developing nations, or in assessing patients with media disorders prior to ophthalmic surgery. [ABSTRACT FROM AUTHOR]