Ovidiu Lungu

• PhD in Social Psychology; postdocs in Neuroscience
• Université de Montréal

ABSTRACT: The term "brain fog" has emerged from the observations of neuropsychiatric conditions present in post-COVID-19 infections. This is characterized by concentration and memory problems, selective attention disorders and difficulties in executive functions, yet it is unclear how long these deficits may persist and which cognitive functions ar...

Somatotopy, the topographical arrangement of sensorimotor pathways corresponding to distinct body parts, is a fundamental feature of the human central nervous system (CNS). Traditionally, investigations into brain and spinal cord somatotopy have been conducted independently, primarily utilizing body stimulations or movements. To date, however, no s...

Somatotopy, the topographical arrangement of sensorimotor pathways corresponding to distinct body parts, is a fundamental feature of the human central nervous system (CNS). Traditionally, investigations into brain and spinal cord somatotopy have been conducted independently, primarily utilizing body stimulations or movements. To date, however, no s...

The development of appropriate and valid multicultural and multilingual instruments research is necessary due to a growing multicultural and multilingual society in the 21st century. We explored the use of a cognitive scale related to subjective complaints, focusing on the first step: a cross-cultural and semantic validation. This study presents th...

Simultaneous functional magnetic resonance imaging (fMRI) of the spinal cord and brain represents a powerful method for examining both ascending sensory and descending motor pathways in humans in vivo . However, its image acquisition protocols, and processing pipeline are less well established. This limitation is mainly due to technical difficultie...

The spinal cord is a critical component of the central nervous system, transmitting and integrating signals between the brain and the periphery via topographically organized functional levels. Despite its central role in sensorimotor processes and several neuromotor disorders, mapping the functional organization of the spinal cord in vivo in humans...

Mapping the neural patterns that drive human behavior is a key challenge in neuroscience. Even the simplest of our everyday actions stem from the dynamic and complex interplay of multiple neural structures across the central nervous system (CNS). Yet, most neuroimaging research has focused on investigating cerebral mechanisms, while the way the spi...

Background: Parkinson's disease (PD) has traditionally been viewed as an α-synucleinopathy brain pathology. Yet evidence based on postmortem human and animal experimental models indicates that the spinal cord may also be affected. Objective: Functional magnetic resonance imaging (fMRI) seems to be a promising candidate to better characterize spi...

Objective: To develop a taxonomy of interventions aimed at reducing emergency department (ED) transfers and/or hospitalizations from long-term care (LTC) homes. Design: A systematic scoping review. Setting and participants: Permanent LTC home residents. Methods: Experimental and comparative observational studies were searched in MEDLINE, CIN...

The spinal cord is important for sensory guidance and execution of skilled movements. Yet its role in human motor learning is not well understood. Despite evidence revealing an active involvement of spinal circuits in the early phase of motor learning, whether long-term learning engages similar changes in spinal cord activation and functional conne...

Background Delirium is a significant cause of morbidity and mortality among older people admitted to both acute and long-term care facilities (LTCFs). Multicomponent interventions have been shown to reduce delirium incidence in the acute care setting (30–73%) by acting on modifiable risk factors. Little work, however, has focused on using this appr...

Most of our knowledge about the human spinal ascending (sensory) and descending (motor) pathways comes from non-invasive electrophysiological investigations. However, recent methodological advances in acquisition and analyses of functional magnetic resonance imaging (fMRI) data from the spinal cord, either alone or in combination with the brain, ha...

The brain detects deviations from intended behaviors by estimating the mismatch between predicted and actual outcomes. Axiomatic to these computations are salience and valence prediction error signals, which alert the brain to the occurrence and value of unexpected events. Despite the theoretical assertion of these prediction error signals, it is u...

In the absence of any task, both the brain and spinal cord exhibit spontaneous intrinsic activity organised in a set of functionally relevant neural networks. However, whether such resting-state networks (RSNs) are interconnected across the brain and spinal cord is unclear. Here, we used a unique scanning protocol to acquire functional images of bo...

The possibilities of substantial long-term improvement of predictive timing might be sometimes seen as limited, with scanty information of neural substrates underlying the potential learning process. To address this issue, we have investigated the performance of 21 baseball professionals and 21 matched controls in a predictive motor timing task pre...

Background: Parkinson's disease (PD) results in both motor and non-motor symptoms. Traditionally, the underlying mechanism of PD has been linked to neurodegeneration of the basal ganglia. Yet it does not adequately account for the non-motor symptoms of the disease, suggesting that other brain regions may be involved. One such region is the cerebell...

Recently, an increasing interest in investigating interactions between brain regions using functional connectivity (FC) methods has shifted the initial focus of cognitive neuroimaging research from localizing functional circuits based on task activation to mapping brain networks based on intrinsic FC dynamics. Leveraging the advantages of the latte...

Background: Schizophrenia is characterized by self-disturbances, including impaired self-evaluation abilities and source monitoring. The cortical midline structures (e.g., medial prefrontal cortex, anterior and posterior cingulate cortex, and precuneus) and the temporoparietal junction are known to play a key role in self-related processing. In the...

Although recently conceptualized as a neural node essential for a vast spectrum of associative and cognitive processes, the cerebellum has largely eluded attention in the research of aging, where it is marginalized mainly to structural analyses. In the current cross-sectional study of 67 healthy subjects of various ages (20 to 76 years), we sought...

Among healthy volunteers in psychiatric brain functional magnetic resonance imaging (fMRI) research studies, the prevalence of incidentalomas can be as high as 34%, of which 10% show clinical significance. An incidentaloma is a lesion found by coincidence without clinical symptoms or suspicion. Like lesions and other types of accidental findings, i...

FMRI studies investigating the acquisition of sequential motor skills in humans have revealed learning-related functional reorganizations of the cortico-striatal and cortico-cerebellar motor systems accompanied with an initial hippocampal contribution. Yet, the functional significance of these activity level changes remains ambiguous as they convey...

Background: It has been proposed that physical exercise can help improve upper limb functions in Parkinson’s disease (PD) patients; yet evidence for this hypothesis is limited. Objective: To assess the effects of aerobic exercise training (AET) on general upper limb functions in sedentary people with PD and healthy adults (HA). Methods: Two groups,...

There is now ample evidence that sleep spindles play a critical role in the consolidation of newly acquired motor sequences. Previous studies have also revealed that the interplay between different types of sleep oscillations (e.g. spindles, slow waves, sharp-wave ripples) promotes the consolidation process of declarative memories. Yet the function...

FMRI studies investigating the acquisition of sequential motor skills in humans have revealed learning-related functional reorganizations of the cortico-striatal and cortico-cerebellar motor systems in link with the hippocampus. Yet, the functional significance of these activity level changes is not fully understood as they convey the evolution of...

Patients with schizophrenia often demonstrate impairment in social-cognitive functions as well as disturbances in large-scale network connectivity. The ventro-medial prefrontal cortex (vmPFC) is a core region of the default mode network, with projections to limbic structures. It plays an important role in social and emotional decision making. We in...

Despite the high prevalence of suicidal ideas/attempts in schizophrenia, only a handful of neuroimaging studies have examined the neurobiological differences associated with suicide risk in this population. The main objective of the current exploratory study is to examine the neurofunctional correlates associated with a history of suicide attempt i...

We investigated the influence of anger processing on cognitive control in male schizophrenia patients presenting violent behaviors. We recruited 23 patients without and 24 patients with (SCZ+V) a history of violent behaviors, as well as 22 healthy non-violent men. Participants were administered an affective (angry-neutral faces) Go/NoGo task while...

The learning of sequential motor behaviors involves the integration of separate movements into a unified and coordinated sequence of actions through practice. Neuroimaging studies in humans strongly suggest that this form of procedural memory relies on the progressive reorganization of motor-related neural networks over the course of learning. This...

Transferring patients from the nursing home (NH) to the acute care setting is associated with increased mortality and morbidity. To date, several types of interventions seeking to reduce potentially avoidable hospital transfers have been proposed, yet there is a lack of systematic evidence regarding their effectiveness. In response to this knowledg...

Background Cigarette smoking is highly prevalent in schizophrenia and is one of the main factors contributing to the significantly decreased life expectancy in this population. Schizophrenia smokers, compared to their counterparts with no comorbid psychiatric disorder, are largely unaware and indifferent to the long-term negative consequences of ci...

Background: Cigarette smoking is highly prevalent in schizophrenia and is one of the main factors contributing to the significantly decreased life expectancy in this population. Schizophrenia smokers, compared to their counterparts with no comorbid psychiatric disorder, are largely unaware and indifferent to the long-term negative consequences of c...

Motor memory consolidation is thought to depend on sleep-dependent reactivation of brain areas recruited during learning. However, up to this point, there has been no direct evidence to support this assertion in humans, and the physiological processes supporting such reactivation are unknown. Here, simultaneous electroencephalographic and functiona...

Functional and structural brain changes associated with the cognitive processing of emotional visual stimuli were assessed in schizophrenic patients after 16 weeks of antipsychotic treatment with ziprasidone. Forty-five adults aged 18 to 40 were recruited: 15 schizophrenia patients (DSM-IV criteria) treated with ziprasidone (mean daily dose = 120 m...

Although specialized communication tools can effectively reduce acute care transfers, few studies have assessed the factors that may influence the use of such tools by nursing staff at the individual level. We evaluated the associations between years of experience, tool-related training, nursing attitudes, and intensity of use of a communication to...

Background: Although dystonia is traditionally conceptualized as a basal ganglia disorder, increasing interest has been directed at a different neural network node, the cerebellum, which may play a significant role in the pathophysiology of dystonia. Abnormal sensorimotor processing and disturbed motor schemes, possibly attributable to cerebellar...

Background: There is increasing evidence that executive functions and attention are associated with gait and balance, and that this link is especially prominent in older individuals or those who are afflicted by neurodegenerative diseases that affect cognition and/or motor functions. People with Parkinson’s disease (PD) often present gait disturbance...

Sentences such as The author started the book are indeterminate because they do not make explicit what the subject (the author) started doing with the object (the book). In principle, indeterminate sentences allow for an infinite number of interpretations. One theory, however, assumes that these sentences are resolved by semantic coercion, a lingui...

Essential tremor (ET), clinically characterized by postural and kinetic tremors, predominantly in the upper extremities, originates from pathological activity in the dynamic oscillatory network comprising the majority of nodes in the central motor network. Evidence indicates dysfunction in the thalamus, the olivocerebellar loops, and intermittent c...

Background: Aerobic exercise training (AET) has been shown to provide general health benefits, and to improve motor behaviours in particular, in individuals with Parkinson's disease (PD). However, the influence of AET on their motor learning capacities, as well as the change in neural substrates mediating this effect remains to be explored. Objecti...

Supplementary material

Older adults show impaired consolidation in motor sequence learning (MSL) tasks, failing to demonstrate the sleep-dependant performance gains usually seen in young individuals. To date, few studies have investigated the white matter substrates of MSL in healthy aging, and none have addressed how fiber pathways differences may contribute to the age-...

We previously demonstrated that predictive motor timing (i.e., timing requiring visuomotor coordination in anticipation of a future event, such as catching or batting a ball) is impaired in patients with spinocerebellar ataxia (SCA) types 6 and 8 relative to healthy controls. Specifically, SCA patients had difficulties postponing their motor respon...

Background Evidence suggests a 2.1–4.6 times increase in the risk of violent behavior in schizophrenia compared to the general population. Current theories propose that the processing of negative emotions is defective in violent individuals and that dysfunctions within the neural circuits involved in emotion processing are implicated in violence. A...

Although numerous studies have convincingly demonstrated that sleep plays a critical role in motor sequence learning (MSL) consolidation, the specific contribution of the different sleep stages in this type of memory consolidation is still contentious. To probe the role of stage 2 non-REM sleep (NREM2) in this process, we used a conditioning protoc...

Using the remarkable overlap between brain circuits affected in Parkinson’s disease (PD) and those underlying motor sequence learning, we may improve the effectiveness of motor rehabilitation interventions by identifying motor learning facilitators in PD. For instance, additional sensory stimulation and task cueing enhanced motor learning in people...

De nombreuses études ont montré qu’il y a une association entre les comportements violents et le fait d’avoir un diagnostic de schizophrénie (Sz) [1,2]. Cependant, il a aussi été démontré que seulement une minorité des patients sera violente [3]. Plusieurs études ont considéré ces phénomènes afin de mieux identifier les personnes à risque et, par l...

To examine the neural correlates of emotion processing in treatment-resistant patients with schizophrenia (SCZ-TR). Twenty-two SCZ-TR patients on clozapine, 24 schizophrenia patients on antipsychotics other than clozapine, and 39 healthy controls were scanned using functional neuroimaging while viewing positive, negative and neutral images. Emotion...

Recent advances in the field of cognitive neuroscience have revealed that direct gaze modulates activity in cortical and subcortical key regions of the 'social brain network', including the inferior frontal gyrus (IFG) and the anterior rostral medial prefrontal cortex (arMPFC). However, very little is known about how direct gaze is processed during...

The spinal cord participates in the execution of skilled movements by translating high-level cerebral motor representations into musculotopic commands. Yet, the extent to which motor skill acquisition relies on intrinsic spinal cord processes remains unknown. To date, attempts to address this question were limited by difficulties in separating spin...

A large body of neurophysiological work in animals and humans has revealed that the spinal cord is not a simple bystander of the central nervous system or just a bundle of nerves relaying signals from brain to the muscles and from sensory organs back to the brain. Yet, the spinal cord is like a Cinderella for the neuroimaging community at large, wh...

The salience network (SN), a set of brain regions composed of the anterior fronto-insular cortex (aFI) and the anterior cingulate cortex (ACC), is usually involved in interoception, self-regulating, and action selection. Accumulating evidence indicates that dysfunctions in this network are associated with various pathophysiological deficits in both...

Minor motor and sensory impairments, including movement sequencing, are frequent symptoms in schizophrenia. In a previous study (Kasparek et al., 2012) we showed abnormal cortico-cerebellar functional connectivity during execution of motor task only in schizophrenia patients (SZP) with sequencing deficit. This suggests that the abnormal connectivit...

Pressure ulcer prevention is an important long-term care (LTC) quality indicator. While the Braden Scale is a recommended risk assessment tool, there is a paucity of information specifically pertaining to its validity within the LTC setting. We therefore undertook a systematic review and meta-analysis comparing Braden Scale predictive and concurren...

Motor sequences can be learned using an incremental approach by starting with a few elements and then adding more as training evolves (e.g., learning a piano piece); conversely, one can use a global approach and practice the whole sequence in every training session (e.g., shifting gears in an automobile). Yet, the neural correlates associated with...

Background / Purpose: Older adults exhibit normal motor sequence learning (MSL), but show impaired consolidation, failing to demonstrate the spontaneous gains in performance usually seen in young adults following a retention interval that includes sleep. The brain regions functionally engaged in explicit MSL have been extensively described, yet t...

Introduction Published studies demonstrated that the cerebellum and basal ganglia participate in various motor and non-motor task related to prediction. In a series of behavioural and functional imaging studies we studied different populations of patients with movements disorders to clarify the role of the cerebellum and basal ganglia with respect...

Objectives.This study assessed the effect of aging on 3 attentional control functions (ACFs)-shifting, inhibition, and updating-and on their contribution to working memory (WM) tasks. Complex WM tasks (the Brown-Peterson procedure, the reading span, and the alpha span) and tasks used to derive composite measures of the ACFs were administered to 75...

The purpose of this study was to investigate the predictive function of sleep spindles in motor sequence consolidation. BOLD responses were acquired in 10 young healthy subjects who were trained on an explicitly known 5-item sequence using their left nondominant hand, scanned at 9:00 pm while performing that same task and then were retested and sca...

Motor learning has mostly been studied in laboratory settings where participants execute the task alone, unlike in real life, where people perform activities together with others. Recent discovery of mirror neuron system (MNS)—linking perception of others' actions and execution of our own—makes the scarcity of studies on social aspects of motor lea...

The cerebellum, basal ganglia (BG), and other cortical regions, such as supplementary motor area (SMA) have emerged as important structures dealing with various aspects of timing, yet the modulation of functional connectivity between them during motor timing tasks remains unexplored. We used dynamic causal modeling to investigate the differences in...

Although dystonia has traditionally been regarded as a basal ganglia dysfunction, recent provocative evidence has emerged of cerebellar involvement in the pathophysiology of this enigmatic disease. This review synthesizes the data suggesting that the cerebellum plays an important role in dystonia etiology, from neuroanatomical research of complex n...

Motor sequence learning is known to rely on more than a single process. As the skill develops with practice, two different representations of the sequence are formed: a goal representation built under spatial allocentric coordinates and a movement representation mediated through egocentric motor coordinates. This study aimed to explore the influenc...

Traditionally, the pathophysiology of cervical dystonia has been regarded mainly in relation to neurochemical abnormities in the basal ganglia. Recently, however, substantial evidence has emerged for cerebellar involvement. While the absence of neurological "cerebellar signs" in most dystonia patients may be considered at least provoking, there are...

Essential tremor (ET) is the most common movement disorder in humans. It is characterized by a postural and kinetic tremor most commonly affecting the forearms and hands. Isolated head tremor has been found in 1-10% of patients, suggesting that ET may be a composite of several phenotypes. The exact pathophysiology of ET is still unknown. ET has bee...

Previous anatomical volumetric studies have shown that healthy aging is associated with gray matter tissue loss in specific cerebral regions. However, these studies may have potentially missed critical elements of age-related brain changes, which largely exist within interrelationships among brain regions. This magnetic resonance imaging research a...

There is evidence that some atypical antipsychotics, including olanzapine, can produce unwanted metabolic side effects, weight gain and diabetes. However, neuronal correlates of change related to food information processing have not been investigated with these medications. We studied the effect of a pharmacological manipulation with an antipsychot...

Background: Given the undesired metabolic side effects of atypical antipsychotic medication it is important to understand the neuronal basis related to processing of appetite regulation in patients affected by schizophrenia. Methods: Here we used functional magnetic resonance imaging (fMRI) to assess brain activity in response to food cues and n...