Search results for "Experimental"

Typical asymmetry in the hemispheric activation during an fMRI verbal comprehension paradigm is related to better performance in verbal and non-verba…

2018

Chronic exposure to seizures in patients with left hemisphere (LH) epileptic focus could favor higher activation in the contralateral hemisphere during language processing, but the cognitive effects of this remain unclear. This study assesses the relationship between asymmetry in hemispheric activation during language fMRI and performance in verbal and non-verbal tasks. Whereas prior studies primarily used fMRI paradigms that favor frontal lobe activation and less prominent activation of the medial or superior temporal lobes, we used a verbal comprehension paradigm previously demonstrated to activate reliably receptive language areas. Forty-seven patients with drug-resistant epilepsy candid…

2015

Age is known to affect prefrontal brain structure and executive functioning in healthy older adults, patients with neurodegenerative conditions and TBI. Yet, no studies appear to have systematically investigated the effect of age on cognitive performance in patients with focal lesions. We investigated the effect of age on the cognitive performance of a large sample of tumour and stroke patients with focal unilateral, frontal (n=68), or non-frontal lesions (n=45) and healthy controls (n=52). We retrospectively reviewed their cross sectional cognitive and imaging data. In our frontal patients, age significantly predicted the magnitude of their impairment on two executive tests (Raven's Advanc…

Force Control and Motor Unit Firing Behavior Following Mental Fatigue in Young Female and Male Adults

2020

Purpose: The neuromuscular mechanisms leading to impaired motor performance in the presence of mental fatigue remain unclear. It is also unknown if mental fatigue differentially impacts motor performance in males and females. The purpose of this study was to assess the impact of mental fatigue on force production and motor unit (MU) firing behavior in males and females. Methods: Nineteen participants performed 10-s isometric dorsiflexion (DF) contractions at 20 and 50% maximum voluntary contraction (MVC) before, during, and after completing 22 min of the psychomotor vigilance task (PVT), to induce mental fatigue. The DF force and indwelling MU firing behavior of the tibialis anterior (TA) w…

Linguistic multifeature MMN paradigm for extensive recording of auditory discrimination profiles

2011

We studied whether a multifeature mismatch negativity (MMN) paradigm using naturally produced speech stimuli is feasible for studies of auditory discrimination accuracy of adult participants. A naturally produced trisyllabic pseudoword was used in the paradigm, and MMNs were recorded to changes that were acoustic (changes in fundamental frequency or intensity) or potentially phonological (changes in vowel identity or vowel duration). All the different changes were presented in three different word segments (initial, middle, or final syllable). All changes elicited an MMN response, but the vowel duration change elicited a different response pattern than the other deviant types. Changes in vo…

Tactile enumeration: A case study of acalculia

2018

Abstract Enumeration is one of the building blocks of arithmetic and fingers are used as a counting tool in early steps. Subitizing—fast and accurate enumeration of small quantities—has been vastly studied in the visual modality, but less in the tactile modality. We explored tactile enumeration using fingers, and gray matter (GM) changes using voxel-based morphometry (VBM), in acalculia. We examined JD, a 22-year-old female with acalculia following a stroke to the left inferior parietal cortex. JD and a neurologically healthy normal comparison (NC) group reported how many fingers were stimulated. JD was tested at several time points, including at acute and chronic phases. Using the sensory …

Detecting impaired language processing in patients with mild cognitive impairment using around‐the‐ear cEEgrid electrodes

2021

Mild cognitive impairment (MCI) is the term used to identify those individuals with subjective and objective cognitive decline but with preserved activities of daily living and an absence of dementia. Although MCI can impact functioning in different cognitive domains, most notably episodic memory, relatively little is known about the comprehension of language in MCI. In this study, we used around-the-ear electrodes (cEEGrids) to identify impairments during language comprehension in patients with MCI. In a group of 23 patients with MCI and 23 age-matched controls, language comprehension was tested in a two-word phrase paradigm. We examined the oscillatory changes following word onset as a fu…

Amygdala response to anticipation of dyspnea is modulated by 5-HTTLPRgenotype

2015

Dyspnea anticipation and perception varies largely between individuals. To investigate whether genetic factors related to negative affect such as the 5-HTTLPR polymorphism impact this variability, we investigated healthy, 5-HTTLPR stratified volunteers using resistive load induced dyspnea together with fMRI. Alternating blocks of severe and mild dyspnea ("perception") were differentially cued ("anticipation") and followed by intensity and unpleasantness ratings. In addition, volunteers indicated their anticipatory fear during the anticipation periods. There were no genotype-based group differences concerning dyspnea intensity and unpleasantness or brain activation during perception of sever…

Effect of synchronized or desynchronized music listening during osteopathic treatment: An EEG study

2013

While background music is often used during osteopathic treatment, it remains unclear whether it facilitates treatment, and, if it does, whether it is listening to music or jointly listening to a common stimulus that is most important. We created three experimental situations for a standard osteopathic procedure in which patients and practitioner listened either to silence, to the same music in synchrony, or (unknowingly) to different desynchronized montages of the same material. Music had no effect on heart rate and arterial pressure pre- and posttreatment compared to silence, but EEG measures revealed a clear effect of synchronized versus desynchronized listening: listening to desynchroni…

Children with dyslexia reveal abnormal native language representations: Evidence from a study of mismatch negativity

2011

Although a deficit perceiving phonemes, as indexed by the mismatch negativity (MMN), is apparent in developmental dyslexia (DD), studies have not yet addressed whether this deficit might be a result of deficient native language speech representations. The present study examines how a native-vowel prototype and an atypical vowel are discriminated by 9-year-old children with (n 5 14) and without (n 5 12) DD. MMN was elicited in all conditions in both groups. The control group revealed enhanced MMN to the native-vowel prototype in comparison to the atypical vowel. Children with DD did not show enhanced MMN amplitude to the native-vowel prototype, suggesting impaired tuning to native language s…

Consensus protocol for EEG and amplitude-integrated EEG assessment and monitoring in neonates

2021

The aim of this work is to establish inclusive guidelines on electroencephalography (EEG) applicable to all neonatal intensive care units (NICUs). Guidelines on ideal EEG monitoring for neonates are available, but there are significant barriers to their implementation in many centres around the world. These includebarriers due to limited resources regarding the availability of equipment and technical and interpretive round-the-clock personnel. On the other hand, despite its limitations, amplitude-integrated EEG (aEEG) (previously called Cerebral Function Monitor [CFM]) is a common alternative used in NICUs.The Italian Neonatal Seizure Collaborative Network (INNESCO), working with all nation…