Reduction of drive for thinness and body dissatisfaction in people with self-reported dysregulated eating behaviors after intermittent theta burst stimulation (iTBS) of the left dorsolateral prefrontal cortex

Aim: This study aimed to explore the effect of intermittent theta burst stimulation (iTBS) of the right and left dorsolateral prefrontal cortex (DLPFC) in people with self-reported dysregulated eating behaviors but without a diagnosis of eating disorders (EDs). Methods: Participants were randomly divided into two equivalent groups according to the side (right or left) of the hemisphere to be stimulated and they were tested before and after a single iTBS session. Outcome measurements were scores on self-report questionnaires assessing psychological dimensions related to eating behaviors (EDI-3), anxiety (STAI-Y), and tonic electrodermal activity. Results: The iTBS interfered with both psychological and neurophysiological measures. Significant variations of physiological arousal after iTBS of both the right and left DLPFC were witnessed by increased mean amplitude of non-specific skin conductance responses. With regard to the psychological measures, the iTBS on the left DLPFC significantly reduced the scores of the EDI-3 subscales drive for thinness and body dissatisfaction. Interestingly, these two scales are two of the three EDI-3 clinic scales (drive for thinness, body dissatisfaction, and bulimia) used as specific markers to assess the onset and/or maintenance of eating disorders. Conclusion: Our results show that the left DLPFC iTBS has an impact on the psychological dimensions that are risk factors for the onset of eating disorders, suggesting that an altered hemispheric asymmetry similar to that encountered in clinical populations is present in normal subjects even in the absence of clinical symptoms

Modulating memory performance in healthy subjects with Trancranial Direct Current Stimulation over the right dorsolateral prefrontal cortex

Objective The role of the Dorsolateral Prefrontal Cortex (DLPFC) in recognition memory has been well documented in lesion, neuroimaging and repetitive Transcranial Magnetic Stimulation (rTMS) studies. The aim of the present study was to investigate the effects of transcranial Direct Current Stimulation (tDCS) over the left and the right DLPFC during the delay interval of a non-verbal recognition memory task. Method 36 right-handed young healthy subjects participated in the study. The experimental task was an Italian version of Recognition Memory Test for unknown faces. Study included two experiments: in a first experiment, each subject underwent one session of sham tDCS and one session of left or right cathodal tDCS; in a second experiment each subject underwent one session of sham tDCS and one session of left or right anodal tDCS. Results Cathodal tDCS over the right DLPFC significantly improved non verbal recognition memory performance, while cathodal tDCS over the left DLPFC had no effect. Anodal tDCS of both the left and right DLPFC did not modify non verbal recognition memory performance. Conclusion Complementing the majority of previous studies, reporting long term memory facilitations following left prefrontal anodal tDCS, the present findings show that cathodal tDCS of the right DLPFC can also improve recognition memory in healthy subjects

Transcranial Magnetic Stimulation Trains at 1 Hz Frequency of the Right Posterior Parietal Cortex Facilitate Recognition Memory

Neuroimaging, neuropsychological, and brain stimulation studies have led to contrasting findings regarding the potential roles of the lateral parietal lobe in episodic memory. Studies using brain stimulation methods reported in the literature do not offer unequivocal findings on the interactions with stimulation location (left vs. right hemisphere) or timing of the stimulation (encoding vs. retrieval). To address these issues, active and sham 1 Hz repetitive transcranial magnetic stimulation (rTMS) trains of 600 stimuli were applied over the right or left posterior parietal cortex (PPC) before the encoding or before the retrieval phase of a recognition memory task of unknown faces in a group of 40 healthy subjects. Active rTMS over the right but not the left PPC significantly improved non-verbal recognition memory performance without any significant modulation of speed of response when applied before the retrieval phase. In contrast, rTMS over the right or the left PPC before the encoding phase did not modulate memory performance. Our results support the hypothesis that the PPC plays a role in episodic memory retrieval that appears to be dependent on both the hemispheric lateralization and the timing of the stimulation (encoding vs. retrieval)

Impairments in top down attentional processes in right parietal patients: Paradoxical functional facilitation in visual search

AbstractIt is well known that the right posterior parietal cortex (PPC) is involved in attentional processes, including binding features. It remains unclear whether PPC is implicated in top-down and/or bottom-up components of attention. We aim to clarify this by comparing performance of seven PPC patients and healthy controls (HC) in a visual search task involving a conflict between top-down and bottom-up processes. This task requires essentially a bottom-up feature search. However, top-down attention triggers feature binding for object recognition, designed to be irrelevant but interfering to the task. This results in top-down interference, prolonging the search reaction time. This interference was indeed found in our HCs but not in our PPC patients. In contrast to HC, the PPC patients showed no evidence of prolonged reactions times, even though they were slower than the HCs in search tasks without the conflict. This finding is an example of paradoxical functional facilitation (PFF) by brain damage. The PFF effect enhanced our patients’ performance by reducing the top down interference. Our finding supports the idea that right PPC plays a crucial role in top-down attentional processes. In our search tasks, right PPC induces top-down interference either by directing spatial attention to achieve viewpoint invariance in shape recognition or by feature binding

Enhancing memory performance with rTMS in healthy subjects and individuals with Mild Cognitive Impairment: the role of the right dorsolateral prefrontal cortex

A debated question in the literature is the degree of anatomical and functional lateralization of the executive control processes sub-served by the dorsolateral prefrontal cortex (DLPFC) during recognition memory retrieval. We investigated if transient inhibition and excitation of the left and right DLPFC at retrieval by means of repetitive transcranial magnetic stimulation (rTMS) modulate recognition memory performance in 100 healthy controls (HCs) and in eight patients with Mild Cognitive Impairment (MCI). Recognition memory tasks of faces, buildings, and words were used in different experiments. rTMS-inhibition of the right DLPFC enhanced recognition memory in both HCs and MCIs. rTMS-excitation of the same region in HCs deteriorated memory performance. Inhibition of the right DLPFC could modulate the excitability of a network of brain regions, in the ipsilateral as well as in the contralateral hemisphere, enhancing function in HCs or restoring an adaptive equilibrium in MCI

Boosting Phonological Fluency Following Leftward Prismatic Adaptation: A New Neuromodulation Protocol for Neurological Deficits?

Prism adaptation (PA) has been recently shown to modulate a brain frontal-parieto-temporal network, with an increase of excitation of this network in the hemisphere ipsilateral to the side of prismatic deviation. This effect raises the hypothesis that left prismatic adaptation, modulating the excitability of frontal areas of the left hemisphere could modulate subjects’ performance on linguistic tasks that map on those areas. To test this hypothesis, sixty-one healthy subjects participated in experiments in which leftward, rightward or no-PA were applied before the execution of a phonological fluency task, i.e. a task with the strict left hemispheric lateralization and mapping onto frontal areas. Leftward-PA significantly increased the number of words produced compared with the pre-PA (p = .0017), R-PA (p=.00013) and no-PA (p=.0005) sessions. In contrast, rightward-PA did not significantly modulate phonological fluency compared with the pre-PA (p = .92) and no-PA (p = .99) sessions. The effect of leftward PA on phonological fluency correlated with the magnitude of spatial aftereffect, i.e. the spatial bias towards the side of space opposite to prismatic deviation following prisms removal (r = .51; p = .04). The present findings document for the first time modulation of a language ability following prismatic adaptation. The results could have a huge clinical impact on neurological populations, opening new strategies of intervention for language and executive dysfunctions

Improvement of phonemic fluency following leftward prism adaptation

Anatomo functional studies of prism adaptation (PA) have been shown to modulate a brain frontal-parieto-temporal network, increasing activation of this network in the hemisphere ipsilateral to the side of prism deviation. This effect raises the hypothesis that left prism adaptation, modulating frontal areas of the left hemisphere, could modify subjects' performance on linguistic tasks that map on those areas. To test this hypothesis, 51 healthy subjects participated in experiments in which leftward or rightward prism adaptation were applied before the execution of a phonemic fluency task, i.e., a task with strict left hemispheric lateralization onto frontal areas. Results showed that leftward PA significantly increased the number of words produced whereas rightward PA did not significantly modulate phonemic fluency. The present findings document modulation of a language ability following prism adaptation. The results could have a huge clinical impact in neurological populations, opening new strategies of intervention for language and executive dysfunctions

Indagine sulla presenza di Salmonella spp. nelle spezie

In the last decades, food-borne infections and food poisoning, due to spices, have increased, in several European countries. The main cause is the improved consumption of ready-to-eat food and increased use of spices in food. A total of 158 samples of spices were analyzed from 2015 to 2019, they were collected in Palermo district, at commercialization or import phase. All samples were analysed for Salmonella spp. All microorganisms isolated were subjected to antibiotic resistance assay. The results of the analysis showed a satisfying hygienic quality of spices, only four samples (2,5%) of sesame showed the presence of Salmonella spp.. The Salmonella isolated strains showed sensitivity to all antibiotics tested except the ampicillin and gentamicin. The strain of S. Maastricht, instead, showed sensitivity to ampicillin and resistance to gentamicin, kanamycin, streptomycin and tetraciclin

Detection of Arcobacter spp. in food products collected from Sicilia region: A preliminary study

The aim of the study was to evaluate the occurrence of Arcobacter spp. in food samples collected from Sicilia region. A total of 91 food products of animal origin (41 meat, 17 fresh milk, 18 shellfish) and 15 samples of fresh vegetables, were examined by cultural method and confirmed by biochemical analysis and PCR methods. The detection of Arcobacter spp. was performed, after selective enrichment, on two selective agar plates: Arcobacter agar and mCCD (modified charcoal cefoperazone deoxycholate) agar supplemented with CAT (Cefoperazone, Amphotericin B and Teicoplanin). Arcobacter species were isolated using the membrane filtration technique. In 13 (14.3%) out of the 91 tested samples, the presence of Arcobacter spp. was found: the isolates were confirmed by multiplex PCR and identified as belonging to the species A. butzleri and A. cryaerophilus. The highest prevalence rate was observed in chicken meat (8.8%) followed by shellfish (3.3%). Negative results have been obtained for raw milks and vegetables samples. The preliminary study highlights the importance of this emerging pathogen and the need for further studies on its prevalence and distribution in different types of food for human consumption

Food risk associated with vegetable consumption, exposure to antimicrobial-resistant strains and pesticide residues

This preliminary study aimed to detect biological and chemical contaminants in vegetables sold in Sicily for human consumption, assess the spread of antimicrobial-resistant (AMR) strains in these foods, and characterize their antimicrobial-resistance genes. A total of 29 fresh and ready-to-eat samples were analyzed. Microbiological analyses were performed for the detection of Salmonella spp. and the enumeration of Enterococci, Enterobacteriaceae, and Escherichia coli. Antimicrobial resistance was assessed by the Kirby-Bauer method, according to the Clinical and Laboratory Standards Institute guidelines. Pesticides were detected by high-performance liquid chromatography and gas chromatography coupled with mass spectrometry. No samples were contaminated by Salmonella spp., E. coli was detected in 1 sample of fresh lettuce at a low bacterial count (2 log cfu/g). 17.24% of vegetables were contaminated by Enterococci and 65.5% by Enterobacteriaceae (bacterial counts between 1.56 log cfu/g and 5.93 log cfu/g and between 1.6 log cfu/g and 5.48 log cfu/g respectively). From 86.2% of vegetables, 53 AMR strains were isolated, and 10/53 isolates were multidrug resistant. Molecular analysis showed that the blaTEM gene was detected in 12/38 β-lactam-resistant/intermediate-resistant isolates. Genes conferring tetracycline resistance (tetA, tetB, tetC, tetD, tetW) were detected in 7/10 isolates. The qnrS gene was detected in 1/5 quinolone-resistant isolates, the sulI gene was detected in 1/4 sulfonamide-resistant/intermediate-resistant isolates and the sulIII gene was never detected. Pesticides were detected in 27.3% of samples, all of which were leafy vegetables. Despite the satisfactory hygienic status of samples, the high percentage of AMR bacteria detected stresses the need for an effective monitoring of these foods as well as adequate strategies to counteract the spread of AMR bacteria along the agricultural chain. Also, the chemical contamination of vegetables should not be underestimated, especially considering that leafy vegetables are commonly consumed raw and that no official guidelines about maximum residue limits of pesticides in ready-to-eat vegetables are available