Gains and losses in intertemporal preferences: a behavioural study

According to recent evidence (Frederick, Loewenstein, & O’Donoghue, 2002), the traditional Discounted Utility model (Samuelson, 1937) has a limited ability to describe realistic models of behaviour and indeed there are several documented empirical regularities that seem to contradict this statement both in certainty and uncertainty conditions. This study focused on one of the best documented anomalies: sign effect or gain-loss asymmetry (Frederick et al., 2002; Loewenstein & Prelec, 1992; Read, 2004). Specifically, the study investigated the intertemporal preference for symmetric monetary rewards and punishments in certain conditions, and the no wealth effects hypothesis (Dimitri, 2007) by asking subjects to choose between two positive or two negative euro amounts available at different points in time. The experimental design applied here followed the same behavioural pattern of the neuroeconomics’ study on monetary rewards realized by McClure et al. (2004). The results confirmed a gain-loss asymmetry at least for medium and large euro amount and suggested new directions of research.intertemporal preferences; gains; losses; certainty; sign effect .

Time estimation in mild Alzheimer's disease patients

<p>Abstract</p> <p>Background</p> <p>Time information processing relies on memory, which greatly supports the operations of hypothetical internal timekeepers. Scalar Expectancy Theory (SET) postulates the existence of a memory component that is functionally separated from an internal clock and other processing stages. SET has devised several experimental procedures to map these cognitive stages onto cerebral regions and neurotransmitter systems. One of these, the time bisection procedure, has provided support for a dissociation between the clock stage, controlled by dopaminergic systems, and the memory stage, mainly supported by cholinergic neuronal networks. This study aimed at linking the specific memory processes predicted by SET to brain mechanisms, by submitting time bisection tasks to patients with probable Alzheimer's disease (AD), that are known to present substantial degeneration of the fronto-temporal regions underpinning memory.</p> <p>Methods</p> <p>Twelve mild AD patients were required to make temporal judgments about intervals either ranging from 100 to 600 ms (short time bisection task) or from 1000 to 3000 ms (long time bisection task). Their performance was compared with that of a group of aged-matched control participants and a group of young control subjects.</p> <p>Results</p> <p>Long time bisection scores of AD patients were not significantly different from those of the two control groups. In contrast, AD patients showed increased variability (as indexed by increased <it>WR </it>values) in timing millisecond durations and a generalized inconsistency of responses over the same interval in both the short and long bisection tasks. A similar, though milder, decreased millisecond interval sensitivity was found for elderly subjects.</p> <p>Conclusion</p> <p>The present results, that are consistent with those of previous timing studies in AD, are interpreted within the SET framework as not selectively dependent on working or reference memory disruptions but as possibly due to distortions in different components of the internal clock model. Moreover, the similarity between the timing patterns of elderly and AD participants raises the important issue of whether AD may be considered as part of the normal aging process, rather than a proper disease.</p

Sensory Loss Mimicking Cauda Equina Syndrome due to Cervical Spinal Lesion in a Patient with Clinically Isolated Syndrome

We describe the case of a 39-year-old woman with signs and symptoms suggesting cauda equina syndrome. Lumbosacral magnetic resonance imaging (MRI) demonstrated no lesion at this level, while cervical MRI showed a T2-hyperintense lesion in the middle-right anterolateral region of the cervical spinal cord, which may explain the symptoms by involving the anterior spinothalamic tract. We suggest that in cases with cauda equina syndrome presentation and normal lumbosacral MRI, a cervicodorsal lesion should be considered during diagnostic assessment

The place of Free Will: the freedom of the prisoner

Debates about the concept of Free Will date back to ancient times. About 40 years ago Benjamin Libet designed an experiment showing that the conscious intention to move is preceded by a specific pattern of brain activation. His finding suggested that unconscious processes determine our decisions. Libet-style experiments have continued to dominate the debate about Free-Will, pushing some authors to argue that the existence of Free Will is a mere illusion. We believe that this dispute is because we often measure free will using arbitrary human decisions rather than deliberate actions. After reviewing the definition of free will and the related literature we conclude that the scientific evidence does not disprove the existence of Free Will. However, our will encounters several constraints and limitations that should be considered when evaluating our deeds’ personal responsibility

Gains and losses in intertemporal preferences: a behavioural study

The aim of this study was to investigate individual behavior in choosing symmetric monetary gains and losses under certainty. As in previous research, results showed that gains and losses are not equal and seem to be drawn by different internal principles of choice. Subjects preferred to lose sooner in time against average or high losses. Furthermore, considering the proportional difference between short and long-term alternatives of choice, the percentage of responses for early outcomes was increasing for losses and decreasing for gains

Brain air embolism secondary to atrial-esophageal fistula.

Case report of a patient who developed a cerebral air embolism secondary to atrial-esophageal fistula

Uncover the Offensive Side of Disparagement Humor: An fMRI Study

Disparagement humor is a kind of humor that denigrates, belittles an individual or a social group. In the aim to unveil the offensive side of these kinds of jokes, we have run an event-related fMRI study asking 30 healthy volunteers to judge the level of fun of a series of verbal stimuli that ended with a sentence that was socially inappropriate but funny (disparagement joke -DJ), socially inappropriate but not funny (SI) or neutral (N). Behavioral results showed disparagement jokes are perceived as funny and at the same time offensive. However, the level of offense in DJ is lower than that registered in SI stimuli. Functional data showed that DJ activated the insula, the SMA, the precuneus, the ACC, the dorsal striatum (the caudate nucleus), and the thalamus. These activations suggest that in DJ a feeling of mirth (and/or a desire to laugh) derived from the joke (e.g., SMA and precuneus) and the perception of the jokes\u2019 social inappropriateness (e.g., ACC and insula) coexist. Furthermore, DJ and SI share a common network related to mentalizing and to the processing of negative feelings, namely the medial prefrontal cortex, the putamen and the right thalamus

Diagnosis and Treatment of Peripheral and Cranial Nerve Tumors with Expert Recommendations: An EUropean Network for RAre CANcers (EURACAN) Initiative

The 2021 WHO classification of the CNS Tumors identifies as "Peripheral nerve sheath tumors" (PNST) some entities with specific clinical and anatomical characteristics, histological and molecular markers, imaging findings, and aggressiveness. The Task Force has reviewed the evidence of diagnostic and therapeutic interventions, which is particularly low due to the rarity, and drawn recommendations accordingly. Tumor diagnosis is primarily based on hematoxylin and eosin-stained sections and immunohistochemistry. Molecular analysis is not essential to establish the histological nature of these tumors, although genetic analyses on DNA extracted from PNST (neurofibromas/schwannomas) is required to diagnose mosaic forms of NF1 and SPS. MRI is the gold-standard to delineate the extension with respect to adjacent structures. Gross-total resection is the first choice, and can be curative in benign lesions; however, the extent of resection must be balanced with preservation of nerve functioning. Radiotherapy can be omitted in benign tumors after complete resection and in NF-related tumors, due to the theoretic risk of secondary malignancies in a tumor-suppressor syndrome. Systemic therapy should be considered in incomplete resected plexiform neurofibromas/MPNSTs. MEK inhibitor selumetinib can be used in NF1 children ≥2 years with inoperable/symptomatic plexiform neurofibromas, while anthracycline-based treatment is the first choice for unresectable/locally advanced/metastatic MPNST. Clinical trials on other MEK1-2 inhibitors alone or in combination with mTOR inhibitors are under investigation in plexiform neurofibromas and MPNST, respectively

MRI correlates of Parkinson's disease progression: A voxel based morphometry study

We investigated structural brain differences between a group of early-mild PD patients at different phases of the disease and healthy subjects using voxel-based morphometry (VBM). 20 mild PD patients compared to 15 healthy at baseline and after 2 years of follow-up. VBM is a fully automated technique, which allows the identification of regional differences in the gray matter enabling an objective analysis of the whole brain between groups of subjects. With respect to controls, PD patients exhibited decreased GM volumes in right putamen and right parietal cortex. After 2 years of disease, the same patients confirmed GM loss in the putamen and parietal cortex; a significant difference was also observed in the area of pedunculopontine nucleus (PPN) and in the mesencephalic locomotor region (MLR). PD is associated with brain morphological changes in cortical and subcortical structures. The first regions to be affected in PD seem to be the parietal cortex and the putamen. A third structure that undergoes atrophy is the part of the inferior-posterior midbrain, attributable to the PPN and MLR. Our findings provide new insight into the brain involvement in PD and could contribute to a better understanding of the sequence of events occurring in these patients

Interação entre aspecto gramatical e semântico na expressão de perfect universal associado ao passado no português do Brasil

O objetivo geral deste trabalho é contribuir para a investigação acerca da interação entre aspecto gramatical e semântico nas línguas. O objetivo específico é investigar se há e quais são as restrições aspectuais semânticas de uso das morfologias veiculadoras de perfect universal associado ao passado no português do Brasil. As hipóteses postuladas são duas: (i) não há restrições aspectuais semânticas de uso do pretérito imperfeito na veiculação de perfect universal associado ao passado no português do Brasil e (ii) há restrições aspectuais semânticas de uso do auxiliar no pretérito imperfeito + gerúndio na veiculação de perfect universal associado ao passado no português do Brasil. Utilizaram-se dois procedimentos metodológicos: análise de corpus linguístico e aplicação de duas versões de um experimento linguístico, um teste offline de decisão. Os resultados indicaram que ambas as formas verbais postuladas nas hipóteses são empregadas com os quatro tipos de verbo e que a morfologia de pretérito imperfeito é a mais utilizada com todos eles. Logo, apenas a segunda hipótese foi refutada. Os dados sugerem que verbos estativos e pontuais desfavorecem o emprego do auxiliar no pretérito imperfeito + gerúndio