Search results for "Dorsolateral Prefrontal Cortex"

Different Brain Circuitries Mediating Controllable and Uncontrollable Pain.

2015

Uncontrollable, compared with controllable, painful stimulation can lead to increased pain perception and activation in pain-processing brain regions, but it is currently unknown which brain areas mediate this effect. When pain is controllable, the lateral prefrontal cortex (PFC) seems to inhibit pain processing, although it is unclear how this is achieved. Using fMRI in healthy volunteers, we examined brain activation during controllable and uncontrollable stimulation to answer these questions. In the controllable task, participants self-adjusted temperatures applied to their hand of pain or warm intensities to provoke a constant sensation. In the uncontrollable task, the temperature time …

Alterations of perineuronal nets in the dorsolateral prefrontal cortex of neuropsychiatric patients

2019

Abstract Background Alterations in the structure and physiology of interneurons in the prefrontal cortex (PFC) are important factors in the etiopathology of different psychiatric disorders. Among the interneuronal subpopulations, parvalbumin (PV) expressing cells appear to be specially affected. Interestingly, during development and adulthood the connectivity of these interneurons is regulated by the presence of perineuronal nets (PNNs), specialized regions of the extracellular matrix, which are frequently surrounding PV expressing neurons. Previous reports have found anomalies in the density of PNNs in the PFC of schizophrenic patients. However, although some studies have described alterat…

Primary Sensorimotor Cortex Drives the Common Cortical Network for Gamma Synchronization in Voluntary Hand Movements

2018

Background: Gamma synchronization (GS) may promote the processing between functionally related cortico-subcortical neural populations. Our aim was to identify the sources of GS and to analyze the direction of information flow in cerebral networks at the beginning of phasic movements, and during medium-strength isometric contraction of the hand. Methods: We measured 64-channel electroencephalography in 11 healthy volunteers (age: 25 ± 8 years; four females); surface electromyography detected the movements of the dominant hand. In Task 1, subjects kept a constant medium-strength contraction of the first dorsal interosseus muscle, and performed a superimposed repetitive voluntary self-paced br…

Transcranial random noise stimulation over the primary motor cortex in PD-MCI patients: a crossover, randomized, sham-controlled study

2020

AbstractMild cognitive impairment (MCI) is a very common non-motor feature of Parkinson’s disease (PD) and the non-amnestic single-domain is the most frequent subtype. Transcranial random noise stimulation (tRNS) is a non-invasive technique, which is capable of enhancing cortical excitability. As the main contributor to voluntary movement control, the primary motor cortex (M1) has been recently reported to be involved in higher cognitive functioning. The aim of this study is to evaluate the effects of tRNS applied over M1 in PD-MCI patients in cognitive and motor tasks. Ten PD-MCI patients, diagnosed according to the Movement Disorder Society, Level II criteria for MCI, underwent active (re…

Mapping effective connectivity between the frontal and contralateral primary motor cortex using dual-coil transcranial magnetic stimulation

2019

AbstractCytoarchitectonic, anatomical and electrophysiological studies have divided the frontal cortex into distinct functional subdivisions. Many of these subdivisions are anatomically connected with the contralateral primary motor cortex (M1); however, effective neurophysiological connectivity between these regions is not well defined in humans. Therefore, we aimed to use dual-coil transcranial magnetic stimulation (TMS) to map, with high spatial resolution, the effective connectivity between different frontal regions of the right hemisphere and contralateral M1 (cM1). TMS was applied over the left M1 alone (test pulse) or after a conditioning pulse was applied to different grid points co…

2016

The negative interpretation of body sensations (e.g., as sign of a severe illness) is a crucial cognitive process in pathological health anxiety (HA). However, little is known about the nature and the degree of automaticity of this interpretation bias. We applied an implicit association test (IAT) in 20 subjects during functional magnetic resonance imaging (fMRI) to investigate behavioral and neural correlates of implicit attitudes towards symptom words. On the behavioral level, body symptom words elicited strong negative implicit association effects, as indexed by slowed reaction times when symptom words were paired with the attribute “harmless” (incongruent condition) relative to a contro…

Extraction of prefronto-amygdalar pathways by combining probability maps

2008

Many recent studies reported altered functional connectivity within the frontolimbic circuitry in a wide range of neuropsychiatric disorders. However, functional connectivity must rely on structural connections. In this study we applied a novel probabilistic fiber tracking method to assess the structural connectivity between the amygdala and different prefrontal brain regions in vivo. Twenty healthy subjects were investigated with diffusion tensor imaging. Probabilistic fiber tracking was started from the amygdala and different prefrontal brain regions. Resulting probability maps were combined using an extended multiplication of probabilistic maps to identify the most probable anatomical pa…

Wisconsin Card Sorting Test: an indicator of vulnerability to schizophrenia?

1992

The Wisconsin Card Sorting Test (WCST) is a neuropsychological test, hypothesized to be an indicator of dorsolateral prefrontal cortex (DLPFC) functioning. The performance of schizophrenic patients in our sample (off medication) was worse than the performance of healthy controls in all variables of the WCST, including perseverative responses (PR) as well as non-perseverative responses (NPR). The rate of perseverative and non-perseverative responses was neither a function of the severity of the illness (measured by SANS/SAPS scales) nor the duration of the disease. Healthy siblings of schizophrenic probands revealed more perseverative responses than healthy controls, but did not show any dif…

Linking planning performance and gray matter density in mid-dorsolateral prefrontal cortex: Moderating effects of age and sex

2012

Abstract Planning of behavior relies on the integrity of the mid-dorsolateral prefrontal cortex (mid-dlPFC). Yet, only indirect evidence exists on the association of protracted maturation of dlPFC and continuing gains in planning performance post adolescence. Here, gray matter density of mid-dlPFC in young, healthy adults (18–32 years) was regressed onto performance on the Tower of London planning task while accounting for moderating effects of age and sex on this interrelation. Multiple regression analysis revealed an association of planning performance and mid-dlPFC gray matter density that was especially strong in late adolescence and early twenties. As expected, for males better plannin…

Neural responses to emotional stimuli in comorbid borderline personality disorder and bipolar depression

2010

"\"Borderline personality disorder (BPD) is a severe clinical condition characterised by different maladaptive traits such as impulsivity and affective lability. Mood and emotion dysregulation are core features of affective disorders. Indeed patients affected by mood disorder (MD) have a significantly higher prevalence of comorbid BPD, resulting in more unstable mood and poorer response to medication. Blood oxygen level-dependent functional magnetic resonance imaging has been used to investigate the neural correlates of emotional face processing. Images for each subject were entered into an analysis of variance (ANOVA) dividing participants into three groups (MD, MD + BPD, Controls). MD + B…