Ezequiel Mikulan

University of Milan | UNIMI · Department of Biomedical and Clinical Sciences "Luigi Sacco"

Hemispherotomy is a surgical procedure that disconnects a large portion of the cerebral cortex from cortical and subcortical inputs in patients with severe refractory epilepsy. Whether the disconnected cortex - inaccessible to behavioral assessment - supports consciousness remains unknown. Functional MRI studies have indicated preserved resting-sta...

The human brain exhibits a modular and hierarchical structure, spanning low-order sensorimotor to high-order cognitive/affective systems. What is the causal significance of this organization for brain dynamics and information processing properties? We investigated this question using rare simultaneous multimodal electrophysiology (stereotactic and...

Cortical stimulation with single electrical or magnetic pulses is a popular technique in clinical practice and research. However, we still do not understand the extent to which non-cortical circuits contribute to the associated evoked potentials (EPs). Here we optogenetically dissect the underlying circuit in mice, demonstrating that the late compo...

During development, the brain undergoes radical structural and functional changes following a posterior-to-anterior gradient, associated with profound changes of cortical electrical activity during both wakefulness and sleep. However, a systematic assessment of the developmental effects on aperiodic EEG activity maturation across vigilance states i...

Electrophysiological source imaging (ESI) aims at reconstructing the precise origin of brain activity from measurements of the electric field on the scalp. Across laboratories/research centers/hospitals, ESI is performed with different methods, partly due to the ill-posedness of the underlying mathematical problem. However, it is difficult to find...

Background Cortico-cortical evoked potentials (CCEPs) recorded by stereo-electroencephalography (SEEG) are a valuable tool to investigate brain reactivity and effective connectivity. However, invasive recordings are spatially sparse since they depend on clinical needs. This sparsity hampers systematic comparisons across-subjects, the detection of t...

Background: Cortico-cortical evoked potentials (CCEPs) recorded by stereo-electroencephalography (SEEG) are a valuable clinical tool to investigate brain reactivity and effective connectivity. However, these invasive recordings are spatially sparse since they depend on clinical needs. This sparsity hampers systematic comparisons across-subjects, th...

Although clinical neuroscience and the neuroscience of consciousness have long sought mechanistic explanations of tactile-awareness disorders, mechanistic insights are rare, mainly because of the difficulty of depicting the fine-grained neural dynamics underlying somatosensory processes. Here, we combined the stereo-EEG responses to somatosensory s...

Precisely localizing the sources of brain activity as recorded by EEG is a fundamental procedure and a major challenge for both research and clinical practice. Even though many methods and algorithms have been proposed, their relative advantages and limitations are still not well established. Moreover, these methods involve tuning multiple paramete...

Background Direct cortical perturbations had been used to study state-dependent changes in thalamocortical network. TMS combined with EEG has demonstrated consistent modifications among wakefulness, NREM sleep, and anesthesia; furthermore, these measurements resulted useful in the diagnosis and pathophysiological stratification of patients with dis...

The individual differences approach focuses on the variation of behavioral and neural signatures across subjects. In this context, we searched for intracranial neural markers of performance in three individuals with distinct behavioral patterns (efficient, borderline, and inefficient) in a dual-valence task assessing facial and lexical emotion reco...

Functional shifts (FSs) – morphosyntactically marked words evoking coherent but novel meanings – are ubiquitous in English and, specially, in Shakespearean literature. While their neural signatures have been explored in native speakers, no study has targeted foreign-language users, let alone comparing early and late bilinguals. Here, we administere...

The search for biomarkers of neurodegenerative diseases via fMRI functional connectivity (FC) research has yielded inconsistent results. Yet, most FC studies are blind to non-linear brain dynamics. To circumvent this limitation, we developed a “weighted Symbolic Dependence Metric” (wSDM) measure. Using symbolic transforms, we factor in local and gl...

This study assessed whether bilingual memory is susceptible to the extreme processing demands of professional simultaneous interpreters (PSIs). Seventeen PSIs and 17 non-interpreter bilinguals completed word production, lexical retrieval, and verbal fluency tasks. PSIs exhibited enhanced fluency in their two languages, and they were faster to trans...

Neural synchrony in the γ-band is considered a fundamental process in cortical computation and communication and it has also been proposed as a crucial correlate of consciousness. However, the latter claim remains inconclusive, mainly due to methodological limitations, such as the spectral constraints of scalp-level electroencephalographic recordin...

El modelo actual de la tarea de Generalización Temporal Episódica (GTE), donde los participantes juzgan si pares de estímulos auditivos son iguales en duración, predice que los resultados son independientes de la escala y orden de presentación de los estímulos. Para evaluar estas predicciones, se realizaron tres experimentos con duraciones estándar...

Interoception, the monitoring of visceral signals, is often presumed to engage attentional mechanisms specifically devoted to inner bodily sensing. In fact, most standardized interoceptive tasks require directing attention to internal signals. However, most studies in the field have failed to compare attentional modulations between internally- and...

Developing effective and affordable biomarkers for dementias is critical given the difficulty to achieve early diagnosis. In this sense, electroencephalographic (EEG) methods offer promising alternatives due to their low cost, portability, and growing robustness. Here, we relied on EEG signals and a novel information-sharing method to study resting...

Background: Alzheimer's disease (AD) as a disconnection syndrome disrupts both brain information sharing and memory binding functions. The extent to which these two phenotypic expressions are shared pathophysiological mechanisms remains unknown. Objective: To unveil the electrophysiological correlates of integrative memory impairments in AD towa...

Recent works evince the critical role of visual short-term memory (STM) binding deficits as a clinical and preclinical marker of Alzheimer’s disease. These studies suggest a potential role of posterior brain regions in both the neurocognitive deficits of Alzheimer’s patients and STM binding in general. Thereupon, we surmised that stimulation of the...

The current model of the Episodic Temporal Generalization task, where subjects have to judge whether pairs of auditory stimuli are equal in duration, predicts that results are scale-free and unaffected by the presentation order of the stimuli. To test these predictions, we conducted three experiments assessing sub- and supra-second standards and ta...

Consciousness impairments have been described as a cornerstone of epilepsy. Generalized seizures are usually characterized by a complete loss of consciousness, whereas focal seizures have more variable degrees of responsiveness. In addition to these impairments that occur during ictal episodes, alterations of consciousness have also been repeatedly...

View largeDownload slide Central to moral cognition is the detection of intentional harm. Using direct electrophysiological recordings in human subjects, Hesse et al. show that scenes of intentional harm induce early activation of the amygdala. This activation predicts intention attribution and engages a frontotemporal network, supporting the ‘man...

These authors contributed equally to this work. A decisive element of moral cognition is the detection of harm and its assessment as intentional or unintentional. Moral cognition engages brain networks supporting mentalizing, intentionality, empathic concern and evaluation. These networks rely on the amygdala as a critical hub, likely through front...

A decisive element of moral cognition is the detection of harm and its assessment as intentional or unintentional. Moral evaluation engages brain networks supporting mentalizing, intentionality, empathic concern and evaluation. This network relies on the amygdala as a critical hub, likely through frontotemporal connections indexing stimulus salienc...

The relationship between ongoing brain interoceptive signals and emotional processes has been addressed only indirectly through external stimulus-locked measures. In this study, an internal body trigger (heart evoked potential, HEP) was used to measure ongoing internally triggered signals during emotional states. We employed high-density electroenc...

Emerging theories on embodied cognition have caused high expectations, ambitious promises, and strong controversies. Several criticisms have been explained elsewhere (Mahon and Caramazza, 2008; Cardona et al., 2014) and will not be discussed further here. In this paper, we will focus on a specific explanatory strategy frequently assessed by the rad...

Research suggests that individuals with different attachment patterns process social information differently, especially in terms of facial emotion recognition. However, few studies have explored social information processes in adolescents. This study examined the behavioral and ERP correlates of emotional processing in adolescents with different a...

t is commonly assumed thatearly emotional signals provide relevant informationfor social cognition tasks. The goal of this study was to test the association between (a) cortical markers of face emotional processing and (b) social-cognitive measures,and also to build a model which can predictthis association (a & b) in healthy volunteers as well as...

The activity of the anterior cingulate cortex (ACC) has been related to decision-making (Gehring and Willoughby, 2002; Sanfey et al., 2003; Mulert et al., 2008), socially-driven interactions (Sanfey et al., 2003; Rigoni et al., 2010; Etkin et al., 2011), and empathy-related responses (van Veen and Carter, 2002; Gu et al., 2010; Lamm et al., 2011)....