Ricerc@Sapienza

Our decisions often depend on multiple sensory experiences separated by time delays. The brain can remember these experiences and, simultaneously, estimate the timing between events. To understand the mechanisms underlying working memory and time encoding, we analyze neural activity recorded during delays in four experiments on nonhuman primates. To disambiguate potential mechanisms, we propose two analyses, namely, decoding the passage of time from neural data and computing the cumulative dimensionality of the neural trajectory over time.

Amyotrophic lateral sclerosis (ALS) is a complex genetic, late age-onset, progressive neurodegenerative disorder leading to the death of upper and lower motor neurons. Life expectancy after diagnosis is short due to the ongoing degeneration and to the lack of effective treatments. Axonal alterations, mitochondrial deficits, RNA changes, protein misfolding and turnover, glial dysfunction and hyperexcitability are key players in molecular mechanisms involved in the degeneration of motor neurons.

The gliotransmitter glutamate in different brain regions modulates neuronal excitability and synaptic transmission through a variety of mechanisms. Among the hallmarks of astrocytic glutamate release are the slow depolarizing inward currents (SICs) in neurons mediated by N-methyl-d-aspartate receptor activation. Different stimuli that evoke Ca 2+ elevations in astrocytes induce neuronal SICs suggesting a Ca 2+ -dependent exocytotic glutamate release mechanism of SIC generation.

Previous studies have shown that rats trained to self-administer heroin and cocaine exhibit opposite preferences, as a function of setting, when tested in a choice paradigm. Rats tested at home prefer heroin to cocaine, whereas rats tested outside the home prefer cocaine to heroin. Here, we investigated whether drug history would influence subsequent drug preference in distinct settings. Based on a theoretical model of drug-setting interaction, we predicted that regardless of drug history rats would prefer heroin at home and cocaine outside the home.

A large body of evidence that has accumulated over the past decade strongly supports the role of inflammation in the pathophysiology of human epilepsy. Specific inflammatory molecules and pathways have been identified that influence various pathologic outcomes in different experimental models of epilepsy. Most importantly, the same inflammatory pathways have also been found in surgically resected brain tissue from patients with treatment-resistant epilepsy. New antiseizure therapies may be derived from these novel potential targets.

Objectives: Thrombospondins, which are known to interact with the ?2? subunit of voltage-sensitive calcium channels to stimulate the formation of excitatory synapses, have recently been implicated in the process of epileptogenesis. No studies have been so far performed on thrombospondins in models of absence epilepsy. We examined whether expression of the gene encoding for thrombospondin-1 was altered in the brain of WAG/Rij rats, which model absence epilepsy in humans.

Despite decades of research on neurobiological mechanisms of psychostimulant addiction, the only effective treatment for many addicts is contingency management, a behavioral treatment that uses alternative non-drug reward to maintain abstinence. However, when contingency management is discontinued, most addicts relapse to drug use. The brain mechanisms underlying relapse after cessation of contingency management are largely unknown, and, until recently, an animal model of this human condition did not exist.

In astrocytes, the intracellular calcium (Ca2+) signaling mediated by activation of metabotropic glutamate receptor 5 (mGlu5) is crucially involved in the modulation of many aspects of brain physiology, including gliotransmission. Here, we find that the mGlu5-mediated Ca2+ signaling leading to release of glutamate is governed by mGlu5 interaction with Homer1 scaffolding proteins. We show that the long splice variants Homer1b/c are expressed in astrocytic processes, where they cluster with mGlu5 at sites displaying intense local Ca2+ activity.

The assertion that humans differ from animals in their use of lan- guage has been the subject of much discussion as scientists have investi- gated language use by non-human species. This paper considers Claude Perrault’s views on animal language and cognition. One of the leader members of the Early Parisian Académie Royale des Sciences, where comparative anatomy emerged in the late seventeenth century, Claude Perrault rejects both the Cartesian hypothesis of beasts as mere automa- ta and of Pineal Gland as siège de l’âme within the human brain.

This paper considers Claude Perrault’s views on animal language
and cognition, one of the leader members of the early Parisian Académie
royale des Sciences, where comparative anatomy emerged in the late seventeenth
century. Perrault rejects both the Cartesian hypothesis of beasts as
mere automata and of the Pineal Gland as siège de l’âme within the human
brain. He conceives the animal soul as an immaterial and cognitive agent
spread in the whole body, involved in the functional regulation of the all life