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Riassunto. Ennio De Renzi (1924-2014), medico e neurologo, è il fondatore della neuropsicologia italiana moderna. De Renzi non soltanto svolse importanti ricerche, ma dettò anche principi metodologici, superando le insufficienze dell’osservazione clinica tradizionale, qualitativa e rivolta al «caso appariscente»: la ricerca va svolta in gruppi di pazienti; l’esame è standardizzato; le prestazioni dei pazienti vanno confrontate con quelle di persone non cerebrolese, con procedure statistiche. Questo metodo, cui tutt’oggi ancora si ispirano gli studi «di gruppo», assegna un ruolo minore ai «casi singoli». Questi, tuttavia, che pure possono esser condotti in accordo con le raccomandazioni di De Renzi, hanno dato e danno un contributo importante allo studio dell’organizzazione funzionale dei processi cognitivi e delle loro basi neurali.

Left neglect dyslexia (ND) is a component deficit of the syndrome of spatial unilateral neglect (USN) that is frequently associated with manifestations of USN outside the reading domain, conjuring up a double dissociation of deficits, and prima facie suggesting the independence of these putative discrete components of USN. However, while the number of right-brain-damaged patients with left USN without ND is quite sizeable across studies, right-brain-damaged patients with left ND without any other manifestation of left USN are quite rare, some with bilateral damage, one with a developmental disorder. This asymmetry supports the suggestion that ND is an intrinsic component of extra-personal USN, that shares with it most of the affected processes and representations of near extra-personal space. In line with this conclusion, the severity of left ND has been repeatedly found to be related with that of other manifestations of extra-personal USN, outside the reading domain. Furthermore, the sensory lateralized stimulations (caloric and galvanic vestibular, visual optokinetic, neck muscle vibration, head and trunk rotation, visuo-motor adaptation to optical prisms that displace the visual scene laterally), and transcranial magnetic stimulations of the brain, overall modulate left ND, as other manifestations of extra-personal USN. ND may be temporarily improved, worsened or left unchanged, according to the directionality of the stimulation. These effects appear to involve primarily egocentric/viewer/centred representations of written material, both lexical and non-lexical in nature (words, nonwords, text). Importantly, results from experimental, single session, paradigms, have been used to develop successful rehabilitation paradigms of ND.

Introduction : Despite tDCS is increasingly used in experimental and clinical settings, its precise mechanisms remain largely unknown. At a neuronal level, tDCS modulates the cortical excitability by shifting the resting membrane potential in a polarity-dependent way: anodal stimulation increases the spontaneous firing rate, while cathodal decreases it. So far, the neurophysiological underpinnings of the immediate and delayed effects of tDCS are still unclear, as well as, how the stimulation of a given cerebral region may affect the activity of anatomically connected regions. In a previous study it has been investigated the tDCS anodal’s effect on the cortical excitability, by the means of TMS-EEG, showing a diffuse rise of cortical excitability in a bilateral fronto-parietal networks. Methods : Fifteen healthy, right-handed volunteers participated in the study. Single pulse TMS was delivered over the left posterior parietal cortex (PPC), before, during, and after a 10 minutes long session of cathodal tDCS stimulation over the right PPC, while EEG was recorded from 60 channels. For each TMS session, indexes of global and local cerebral excitability were obtained, computed as global and local mean field power (Global Mean Field Power, GMFP and Local Mean Field Power, LMFP) on the mean TMS-evoked potentials (TEPs) for three temporal windows: 0-50, 50-100 and 100-150 ms. The global index was computed on all the 60 channels. While, the local indexes were computed in four different clusters of electrodes: left and right, in frontal and parietal regions. Results : The preliminary results show no differences in both the TMS sessions during and after cathodal tDCS compared to pre-stimulation one, both at global and local level. A further test using bayesian analysis was performed, providing a moderate indication toward null hypothesis. Discussion : These results are consistent with the literature in which the coupling of anodal-excitatory and cathodal-inhibitory effects are well established in the sensory and motor domains, both at physiological and behavioral levels, while the evidence is more controversial for higher-level mental activity. References : Bindman L. et al. Nature. (1962) 196:584e585. Jacobson L.et al. Exp Brain Res. (2012) 216(1):1-10. Romero Lauro L. J. Et al. Cortex, (2014) 58:99e111

Despite transcranial direct current stimulation (tDCS) is a widely used non-invasive brain stimulation techniques, the cathodal tDCS effects on task performance are still controversial and unclear. A deeper understanding of the plastic changes induced by cathodal tDCS would be crucial to improving the refinement of stimulation protocols for clinical and research purposes. In a previous study, we investigated the effect of cathodal tDCS on cortical excitability at a resting state, using a combination of Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG). Results showed no significant modulation effects during and after cathodal stimulation in comparison to a pre-tDCS session. In the present study, we used the same paradigm to study the effect of cathodal tDCS during a task. Single TMS pulses were delivered over the left posterior parietal cortex (PPC), before and after 15 minutes of cathodal or sham tDCS over the right PPC, while recording hd-EEG. During the tDCS stimulation, the subjects were involved in a Posner task that requires visual-attentional abilities, likely involving the PPC. We opted for the Posner task in our experimental protocol on the basis of the results of a pilot study in which we found that cathodal tDCS over the right PPC reduced the performance at the same task, increasing reaction times. As in the previous study, we estimated the indexes of global and local cortical excitability, both at sensors and cortical sources level. At sensors, global and local mean field power (GMFP and LMFP) were computed for three temporal windows (0-50, 50-100 and 100-150 ms), in all channels (GMFP), and in four different clusters of electrodes (LMFP, left and right, in frontal and parietal regions). After source reconstruction, Significant Current Density was computed at a global level, and in four Broadmann’s areas (left/right BA 6 and 7). At a behavioural level, we expected to replicate the results of the pilot study; while at a neurophysiological level we predicted a reduction of cortical excitability only in the areas strictly involved in the task performance. Such results would confirm the hypothesis of a causal interaction between the spontaneous ongoing cortical activity and the electric stimulation.

Despite transcranial direct current stimulation (tDCS) is increasingly used in experimental and clinical settings, its precise mechanisms of action remain largely unknown. At a neuronal level, tDCS modulates the cortical excitability by shifting the resting membrane potential in a polarity-dependent way: anodal stimulation increases the spontaneous firing rate in the stimulated region, while cathodal decreases it. So far, the neurophysiological underpinnings of the immediate and delayed effects of tDCS are still unclear, as well as, it is not fully understood how the stimulation of a given cerebral region may affect the activity of anatomically connected regions. In a previous study it has been investigated the tDCS anodal’s role in the cortical excitability, by a combination of Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG). Results showed a diffuse rise of cortical excitability in a bilateral fronto-parietal networks. In the present study, we used the same technique and methodological setting in order to explore local and global cortical excitability modulation during and after cathodal tDCS. Single pulse TMS was delivered over the left posterior parietal cortex (PPC), before, during, and after 10 minutes of tDCS over the right PPC, while EEG was recorded from 60 channels. For each session, indexes of global and local cerebral excitability were obtained, computed as global and local mean field power (Global Mean Field Power, GMFP and Local Mean Field Power, LMFP) on mean TMS-evoked potentials (TEPs) for four temporal windows: 0-50, 50-100, 100-150 and 150-200 milliseconds. The global index was computed on all 60 channels. The local indexes were computed in four clusters of electrodes: left and right, in frontal and parietal regions. The preliminary results on nine subjects show no differences in both sessions during and after cathodal tDCS compared to pre-stimulation session. These preliminary results suggest the existence of a difference effect due to anodal and cathodal tDCS stimulation, also in other areas, different from the motor cortex.

A series of five experiments explore the influence of articulatory suppression on immediate memory for auditorily presented items with a view to testing the revised concept of an articulatory loop. The concept of a unitary short-term memory system was subsequently questioned by Baddeley and Hitch, who suggested that it should be replaced by a multi-component working memory. The loop was assumed to hold about 1.5 sec of speech-based material in temporary storage and to be capable of maintaining this by means of articulatory rehearsal. Three variables were manipulated in Experiment 1: the phonological similarity of the material, the rate of presentation and articulatory suppression. The revised model makes a distinction between a phonological store and an articulatory rehearsal process. Material can be registered in the store in two ways, either through articulatory rehearsal, an optional process, or via auditory presentation, a process that leads to obligatory registration.

Da qualche anno anche in Italia si sono a acciate sulla scena del diritto e del processo penale le c.d. neuroscienze,vale a dire quel complesso di discipline che indaga sulle connessioni neuronali dei comportamenti umani. A livello teorico, e de iure condendo, la dottrina penalistica si è, quindi, interrogata sulla possibilità di una “rifondazione” del diritto penale che faccia tesoro delle acquisizioni neuroscienti che (per quanto riguarda, in primis, il possibile superamento del dogma della volontà libera e non determinata). A livello pratico, e de iure condito, si registrano, intanto, alcune applicazioni delle neuroscienze nalizzate a fornire la prova di questo o quell’elemento del reato: questo secondo approccio, indubbiamente più proli co del primo, dopo aver riscosso un iniziale favore presso la giurisprudenza di merito, sembra, tuttavia, ora scontrarsi con un profondo scetticismo da parte della giurisprudenza di legittimità. In recent years, also in Italy the neurosciences, namely the set of scienti c disciplines that investigates, among other topics, the neural basis of human behavior, and its disorders, started to interact with criminal law and criminal procedure. At a theoretical level, and de iure condendo, criminal law scholars investigated then whether criminal law may be “refounded”, also on the basis of scienti c evidence from advances in neuroscience ( rst of all, as to the possible overcoming of the dogma of free and self-determined will). At a practical level, and de iure condito, some applications of the neurosciences, aimed at providing the evidence of one or of another essential element of the crime, are on record: the latter approach, so far apparently more proli c than the former, after having obtained some approval by the decisions of the Italian courts of rst instance and courts of appeals, seems, however, at present to be received with deep skepticism by the Italian Supreme Court.

La stimolazione elettrica transcranica (tDCS) è sempre più impiegata sia in ambito clinico sia sperimentale, nonostante questo i suoi precisi meccanismi di funzionamento rimangono in gran parte sconosciuti. È noto che a livello neuronale, la tDCS modula l’eccitabilità corticale modificando il potenziale di membrana a riposo in modo polarità-dipendente: la stimolazione anodica aumenta il firing rate spontaneo delle regioni direttamente stimolate, al contrario quella catodica lo diminuisce (Bindman et Al, 1964). Tuttavia, le basi neurofisiologiche degli effetti della tDCS, diretti e post-stimolazione, sono ancora poco chiare, così come non si è ancora del tutto compreso come la stimolazione di una data area possa indurre degli effetti anche in regioni anatomicamente connesse a essa (Jacobson et al. 2012). In un precedente lavoro sono stati esplorati gli effetti della stimolazione tDCS anodica sull’eccitabilità corticale tramite l’utilizzo di una tecnica che combina la Stimolazione Magnetica Transcranica (TMS) alla registrazione Elettroencefalografica (EEG). I risultati hanno mostrato un diffuso aumento dell’eccitabilità corticale in un network bilaterale fronto-parietale (Romero Lauro et al., 2014). Nel presente studio è stata utilizzata la stessa tecnica e il medesimo setting sperimentale al fine di esplorare gli effetti di modulazione dell’eccitabilità corticale indotti dalla stimolazione tDCS catodica, sia a livello globale sia a livello locale. Materiali e Metodi È stata applicata la TMS a impulso singolo sulla corteccia parietale posteriore (PPC) sinistra, prima, durante e dieci minuti dopo la stimolazione tDCS in corrispondenza della PPC destra. Durante le tre sessioni di stimolazione sono stati registrati i potenziali evocati dalla TMS (TEPs) mediante una cuffia a sessanta canali. Dei TEPs sono state considerate per l’analisi quattro diverse finestre temporali: 0 (onset TMS) -50, 50-100, 100-150 and 150-200 millisecondi. Per ognuna di esse sono stati ricavati gli indici di eccitabilità corticale, sia globale sia locale, calcolando rispettivamente il Global e Local Mean Field Power (GMFP e LMFP) sulla media dei TEPs. Il GMFP è stato ottenuto analizzando il segnale derivante da tutti i sessanta canali EEG. Il LMFP, invece, è stato calcolato su quattro clusters di elettrodi: parietale destro (CP2, CP4, P2, e P4), parietale sinistro (CP1, CP3, P1, e P3), frontale destro (F2, F6, FC2, e FC6) e frontale sinistro (F1, F5, FC1, e FC3). Risultati e Discussione I risultati preliminari mostrano un’assenza di differenze significative tra le tre condizioni di stimolazione. Un’analisi bayesiana mostra un’indicazione moderata per l’ipotesi nulla. Questi risultati sono in linea con gli studi in letteratura che riportano come gli effetti della tDCS catodica risultino piuttosto controversi quando sono interessate aree che sottendono a funzioni cognitive di ordine superiore (Jacobson et al., 2012). Bibliografia 1. Bindman, L. J., Lippold, O. C., & Redfearn, J. W. (1962). Long-lasting changes in the level of the electrical activity of the cerebral cortex produced by polarizing currents. Nature, 196, 584e585. 2. Jacobson, L., Koslowsky, M., & Lavidor, M. (2012). tDCS polarity effects in motor and cognitive domains: a meta-analytical review. Experimental brain research, 216(1), 1-10. 3. Romero Lauro, L. J., Rosanova, M., Mattavelli, G., Convento, S., Pisoni, A., Opitz, A., et al. (2014). TDCS increases cortical excitability: direct evidence from TMS-EEG. Cortex, 58, 99e111.

Introduction: Sound-induced flash illusions(SIFI) permit to evaluate crossmodal audio-visual perception. When one flash is accompanied by two beeps, it is perceived as two flashes(’fission’illusion); a ‘fusion’ illusion occurs when a single beep causes the fusion of a double flash stimulus. SIFI strictly depends on cortical excitability: healthy controls perceive less illusions by increasing visual cortex excitability through anodal tDCS [1]. Aim: to evaluate if, due to cortical hyperexcitability, differences in SIFI occur in migraine and further changes can be found across migraine cycle, migraine chronification an drug overuse. Methods: we enrolled 64 patients with episodic migraine, 32 with-(MWA) and 32 without-aura(MWO) (42 F, mean age 32,3±16yrs), 44 patients with chronic migraine with medication overuse headache (36 F, mean age 39.2 ±12.2), and 20 healthy controls (13 F, mean age 38±18). All underwent a paradigm for SIFI induction where had to report the number of flashes seen. 13 of MWO and 12 out of MWA were examined in both ictal and interictal phase Results: all migraine groups showed significantly less SIFI than controls (p

In questo capitolo si descrivono i principali metodi per indagare gli effetti della riabilitazione dei deficit neuropsicologici. Sono poi discussi i trattamenti riabilitativi dei principali disordini per i quali sono disponibili le evidenze più ampie: l’afasia, l’amnesia, la malattia di Alzheimer (attivazione cognitiva) e la negligenza spaziale unilaterale. Sono inoltre descritti i trattamenti dei deficit di memoria a breve termine verbale e sensoriali visivi (emianopsia). I trattamenti riabilitativi dell’aprassia, dell’attenzione e dei disturbi del comportamento sono descritti nei rispettivi capitoli (capp. 9, 12 e 16).