Prefrontal Blood Research Articles

Relationship between motor learning and gambling propensity in Parkinson’s disease

ABSTRACT Introduction The basal ganglia and related dopaminergic cortical areas are important neural systems underlying motor learning and are also implicated in impulse control disorders (ICDs). Motor learning impairments and ICDs are frequently observed in Parkinson’s disease (PD). Nevertheless, the relationship between motor learning ability and ICDs has not been elucidated. Methods We examined the relationship between motor learning ability and gambling propensity, a possible symptom for prodromal ICDs, in PD patients. Fifty-nine PD patients without clinical ICDs and 43 normal controls (NC) were administered a visuomotor rotation perturbation task and the Iowa Gambling Task (IGT) to evaluate motor learning ability and gambling propensity, respectively. Participants also performed additional cognitive assessments and underwent brain perfusion SPECT imaging. Results Better motor learning ability was significantly correlated with lower IGT scores, i.e., higher gambling propensity, in PD patients but not in NC. The higher scores on assessments reflecting prefrontal lobe function and well-preserved blood perfusion in prefrontal areas were correlated with lower IGT scores along with better motor learning ability. Conclusions Our findings suggest that better motor learning ability and higher gambling propensity are based on better prefrontal functions, which are in accordance with the theory that the prefrontal cortex is one of the common essential regions for both motor learning and ICDs.

Turmeric root extract supplementation improves pre-frontal cortex oxygenation and blood volume in older males and females: a randomised cross-over, placebo-controlled study

Ageing is associated with endothelial dysfunction and reduced cerebral blood flow and oxygenation. The present study aimed to investigate whether turmeric supplementation could improve cerebral oxygenation and blood volume during brain activation via dynamic handgrip exercise in older males and females. Twelve older males and females were studied using a double-blind, placebo-controlled, cross-over design. Participants ingested turmeric root extract or placebo. Heart rate and blood pressure were measured before and 2 hours after supplementation. Afterward, the exercise protocol was started, and cerebral oxygenation and blood volume were evaluated. During exercise, changes in cerebral oxygenation were higher after turmeric extract supplementation, as was blood volume compared to placebo. Changes in heart rate, systolic blood pressure, and diastolic blood pressure were not significant. The current findings indicate the potential for curcumin as an intervention for improving cerebral oxygenation and blood volume changes in older males and females. Clinical trial registry: NCT04119752.

Metabolomics profiling of valproic acid-induced symptoms resembling autism spectrum disorders using 1H NMR spectral analysis in rat model

ABSTRACT Prenatal exposure to valproic acid (VPA) has been implicated in the manifestation of autism spectrum disorder (ASD)-like behavioral and functional changes both in human and rodents including mice and rats. The objective of this study was to determine metabolomics profiling and biomarkers related to VPA-induced symptoms resembling ASD using proton nuclear magnetic resonance (1H-NMR) spectral data. VPA was administered to pregnant rats at gestation day 12.5 and effects measured subsequently in male 4-week-old offspring pups. The sociability of VPA-treated animals was significantly diminished and exhibited ASD-like behavior as evidenced by reduction of social adaptation disorder and lack of social interactions. To find biomarkers related to ASD, the following were collected prefrontal brain cortices, urine bladder and blood samples directly from heart puncture. In all samples, principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) displayed significant clustering pattern differences between control and treated groups. Valine, taurine, myo-inositol, 3-hydroxybutyrate and 1,3-dihydroxyacetone were significantly decreased in brain cortices in treated rats. Serum metabolites of glucose, creatine phosphate, lactate, glutamine and threonine were significantly increased in VPA-administered animals. Urinary metabolites of pimelate, 3-hydroxyisovalerate and valerate were significantly reduced in VPA-treated rat, whereas galactose and galactonate levels were elevated. Various metabolites were associated with mitochondrial dysfunction metabolism and central nervous system disorders. Data demonstrated that VPA-induced alterations in endogenous metabolites of serum, urine, and brain cortex which might prove useful as biomarkers for symptoms resembling ASD as a model of this disorder.

Changes in Prefrontal Gamma-Aminobutyric Acid and Perfusion After the Computerized Relaxation Training in Women With Psychological Distress: A Preliminary Report.

Computerized relaxation training has been suggested as an effective and easily accessible intervention for individuals with psychological distress. To better elucidate the neural mechanism that underpins the effects of relaxation training, we investigated whether a 10-session computerized relaxation training program changed prefrontal gamma-aminobutyric acid (GABA) levels and cerebral blood flow (CBF) in women with psychological distress. We specifically focused on women since they were reported to be more vulnerable to develop stress-related disorders than men. Nineteen women with psychological distress but without a diagnosis of psychiatric disorders received the 10-day computerized relaxation training program that consisted of 30-min cognitive-relaxation training and 10-min breathing-relaxation training per day. At baseline and post-intervention, perceived stress levels, anxiety, fatigue, and sleep quality were assessed by self-report questionnaires. Brain magnetic resonance spectroscopy and arterial spin labeling scans were also performed before and after the intervention to evaluate GABA levels and relative CBF in the prefrontal region. Levels of perceived stress (t = 4.02, P < 0.001), anxiety (z = 2.33, P = 0.02), fatigue (t = 3.35, P = 0.004), and sleep quality (t = 4.14, P < 0.001) improved following 10 sessions of computerized relaxation training, resulting in a significant relief in composite scores of stress-related symptoms (t = −5.25, P < 0.001). The prefrontal GABA levels decreased (t = 2.53, P = 0.02), while relative CBF increased (t = −3.32, P = 0.004) after the intervention. In addition, a greater increase in relative prefrontal CBF was associated with better composite scores of stress-related symptoms following the intervention (t = 2.22, P = 0.04). The current findings suggest that computerized relaxation training may improve stress-related symptoms through modulating the prefrontal GABA levels and CBF in women with psychological distress.

Comparison of Activation in the Prefrontal Cortex of Native Speakers of Mandarin by Ability of Japanese as a Second Language Using a Novel Speaking Task.

Evidence shows that second language (L2) learning affects cognitive function. Here in this work, we compared brain activation in native speakers of Mandarin (L1) who speak Japanese (L2) between and within two groups (high and low L2 ability) to determine the effect of L2 ability in L1 and L2 speaking tasks, and to map brain regions involved in both tasks. The brain activation during task performance was determined using prefrontal cortex blood flow as a proxy, measured by functional near-infrared spectroscopy (fNIRS). People with low L2 ability showed much more brain activation when speaking L2 than when speaking L1. People with high L2 ability showed high-level brain activation when speaking either L2 or L1. Almost the same high-level brain activation was observed in both ability groups when speaking L2. The high level of activation in people with high L2 ability when speaking either L2 or L1 suggested strong inhibition of the non-spoken language. A wider area of brain activation in people with low compared with high L2 ability when speaking L2 is considered to be attributed to the cognitive load involved in code-switching L1 to L2 with strong inhibition of L1 and the cognitive load involved in using L2.

Discrimination of Verbal/Visuospatial Memory Retrieval Processes by Measuring Prefrontal Lobe Blood Volume With Functional Near-Infrared Spectrometry

In cognitive task execution, retrieval processes transfer memories from long-term storage to working memory, comprising three short-term memories—phonological loop, visuospatial sketchpad, and episodic buffer—controlled by a short-term-memory central executive. The phonological loop and visuospatial sketchpad are prominent in verbal and visuospatial information processing, respectively. Individuals differ in how they retrieve the same information. Discrimination between verbal or visuospatial memory retrieval by monitoring central executive activation is useful. Functional near-infrared spectroscopy (fNIRS) was used to assess blood volume and prefrontal lobe brain activation. Using a novel approach, blood volume during memory retrieval was obtained using fNIRS. To eliminate other factors not related to the central executive activation, a base period was observed. Dynamic range was calculated for both memory retrieval and base periods, and differences obtained at ten positions within the prefrontal lobe were used as features to discriminate between verbal and visuospatial retrieval. For discrimination, k-nearest neighbor (kNN) and support vector machine (SVM) with different kernels were applied. Our method was tested on participants in verbal/visuospatial memory retrieval experiments. As the result, accuracy, positive predictive values, and negative predictive values of kNN and SVM were 1, which indicated that the proposed method successfully discriminated between verbal/visuospatial memory retrieval through prefrontal lobe blood volume observation.

Validation of a HPLC Method for Quantification of Thiamine and Its Phosphate Esters in Rat Brain Tissue

The present data show a fast and efficient biological sample processing method for the extraction of thiamine (vitamin B1) and its mono-(TMP) and di-(TDP) phosphate esters from hippocampus, thalamus and prefrontal cortex (PFC) and blood sample of the rodents. In addition, using the hippocampus and standards of these three compounds we validated an isocratic fluorescence HPLC procedure for a simultaneous detection of them in a single chromatogram within a total run time of about 12 min. Reproducibility for TDP, TMP and B1 was 2.66%, 4.50% and 7.43% (intraday) and 37.54%, 25.39% and 25.87% (interday), respectively. Recovery assays were between 96.0% and 101.7%. The calibration curves were linear and the concentrations of the three compounds, all in nanomolar range, were determined in the brain areas and in the blood samples. When compared to the current methods in the literature, this new method provides information on essential variables, such as linearity range and limit of detection, reproducibility and stability of thiamine, TMP and TDP in rat brain samples. The present data on sample processing and B1 and its phosphate ester level determinations are the first to be validated using hippocampus samples of rats.

(S)-ketamine increases prefrontal cerebral blood flow but not glutamate levels in anterior cingulate cortex in healthy volunteers

(S)-ketamine increases prefrontal cerebral blood flow but not glutamate levels in anterior cingulate cortex in healthy volunteers

Biomarkers of response to transcranial magnetic stimulation in youth with treatment resistant major depression

BackgroundMajor depressive disorder (MDD) affects approximately 15% of youth, half of who do not respond to standard treatment. One promising intervention is repetitive transcranial magnetic stimulation (rTMS). However, response is limited, highlighting the need to focus on biomarkers to predict treatment response.ObjectivesTo explore baseline biomarkers of response associated with rTMS treatment in adolescent MDD.AimsTo determine the association between dorsolateral prefrontal cortex (DLPFC) glutamate levels, cortical thickness, and cerebral blood flow (CBF) with MDD symptomatology decrease after rTMS intervention.MethodsTwenty-four MDD youth underwent 3 weeks of rTMS, baseline and post-intervention magnetic resonance imaging scans, and short echo proton magnetic resonance spectroscopy. Response was determined by a 50% reduction of depression scores.ResultsDepressive symptoms decreased with rTMS (t = 8.304, P = 0.00). Glutamate levels differed significantly between responders and non-responders (t = 2.24, P = 0.0039), where higher glutamate changes were associated with a better response (r = 0.416, P = 0.038). Responders also exhibited thinner DLPFC (r = –0.797, P = 0.000) and lower CBF levels.ConclusionsThe development of biomarkers for rTMS represents a novel and encouraging technique for a personalized and effective treatment while reducing ineffective treatment costs and personal burden in adolescent MDD.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Near-Infrared Spectroscopy as a Useful Research Tool to Measure Prefrontal Cortex Activity During Visually Demanding Near Work

OCCUPATIONAL APPLICATIONS Effort, which overrides the need for rest and recuperation to avoid deterioration in visual performance, is commonplace in many contemporary workplaces. The prefrontal cortex is capable of allocating more mental/physical resources to carry out a given work task in the presence of fatigue. However, adverse musculoskeletal and mental health consequences are an anticipated outcome of this since fatigue is a physiological sign of the need for recuperative rest. This article outlines the current evidence suggesting that probing into prefrontal brain activity with near-infrared spectroscopy could advance progress in visual ergonomic research, and pilot data are provided that exemplify the proposed approach. Improved understanding of the age-related health consequences of straining the brain and/or the eyes “to see well” will likely help ergonomic stakeholders find better methods to meet the needs of safer and more productive work environments.TECHNICAL ABSTRACT Background: Unlike the usual skeletal muscles, ciliary muscles responsible for focusing the crystalline eye lens and extraocular muscles responsible for convergence eye movements appear resistant to fatigue. Purpose: The dual goals of this article are to briefly outline the current evidence that suggests that probing into blood flow and hemodynamic prefrontal brain activity with near-infrared spectroscopy could advance progress in visual ergonomic research and to provide pilot data exemplifying the proposed approach. Methods: The vision task consisted of sustained focusing on a contrast-varying black-and-white Gabor grating. Four participants with a median age of 46 (interquartile range 44–50) fixated the grating from a distance of 65 cm. Three counterbalanced 10-minute tasks required central fixation and accommodation/convergence on the grating target through (i) 0.0 diopter lenses, (ii) −1.5 diopter lenses, and (iii) −3.5 diopter lenses while maintaining maximal focus. Non-invasive measurements of local oxyhemoglobin (HbO2) were quantified with a one-channel near-infrared spectrometer. The near-infrared spectroscopy probe was placed on the prefrontal cortex in the vicinity of the right dorsolateral prefrontal cortex or Brodmann area 46. Accommodation response and contrast threshold were measured in parallel. Results: General estimating equation analyses showed that baseline-subtracted dorsolateral prefrontal cortex blood flow (ΔHbO2) increased significantly over time in all three lens conditions. The effect of time may be caused by a continuous increase in mental effort to compensate for progressively more mental fatigue induced by increased visual attention. The increase of dorsolateral prefrontal cortex ΔHbO2 was also larger in magnitude in participants with larger amplitudes accommodation response (i.e., in participants who minimized deterioration in visual performance). Conclusion: The results from this study indicate that oxyhemoglobin changes recorded over the dorsolateral prefrontal cortex with near-infrared spectroscopy can be used to assay the degree to which the visual system is strained during demanding near work.

Sex differences in COMT polymorphism effects on prefrontal inhibitory control in adolescence.

Catecholamine-0-methyl-transferase (COMT) gene variation effects on prefrontal blood oxygenation-level-dependent (BOLD) activation are robust; however, despite observations that COMT is estrogenically catabolized, sex differences in its prefrontal repercussions remain unclear. Here, in a large sample of healthy adolescents stratified by sex and Val(158)Met genotype (n=1133), we examine BOLD responses during performance of the stop-signal task in right-hemispheric prefrontal regions fundamental to inhibitory control. A significant sex-by-genotype interaction was observed in pre-SMA during successful-inhibition trials and in both pre-SMA and inferior frontal cortex during failed-inhibition trials with Val homozygotes displaying elevated activation compared with other genotypes in males but not in females. BOLD activation in the same regions significantly mediated the relationship between COMT genotype and inhibitory proficiency as indexed by stop-signal reaction time in males alone. These sexually dimorphic effects of COMT on inhibitory brain activation have important implications for our understanding of the contrasting patterns of prefrontally governed psychopathology observed in males and females.

Prefrontal cortical blood flow during a complex navigational task: a functional near Infrared Spectroscopy (fNIRS) study

Prefrontal cortical blood flow during a complex navigational task: a functional near Infrared Spectroscopy (fNIRS) study

Increase of prefrontal cortex blood flow during the performance of the computer version trail making test – the first report

Increase of prefrontal cortex blood flow during the performance of the computer version trail making test – the first report

Increase of prefrontal cortex blood flow during trail making test

Increase of prefrontal cortex blood flow during trail making test

Two Weeks of Daily Left Prefrontal rTMS Further Reduces Prefrontal and Cingulate Blood Flow in Depressed Patients

Two Weeks of Daily Left Prefrontal rTMS Further Reduces Prefrontal and Cingulate Blood Flow in Depressed Patients

Prefrontal cortical blood flow in monozygotic twins concordant and discordant for schizophrenia

Prefrontal cortical blood flow in monozygotic twins concordant and discordant for schizophrenia