Executive function (EF) refers to the higher-order cognitive control process for the attainment of a specific goal. There are several subcomponents of EF, such as inhibition, cognitive shifting, and working memory. Extensive neuroimaging research in adults has revealed that the lateral prefrontal cortex plays an important role in EF. Developmental studies have reported behavioral evidence showing that EF changes significantly during preschool years. However, the neural mechanism of EF in young children is still unclear. This article reviews recent near-infrared spectroscopy (NIRS) research that examined the relationship between the development of EF and the lateral prefrontal cortex. Specifically, this review focuses on inhibitory control, cognitive shifting, and working memory in young children. Research has consistently shown significant prefrontal activation during tasks in typically developed children, but this activation may be abnormal in children with developmental disorders. Finally, methodological issues and future directions are discussed.
prefrontal cortex; executive function; young children; NIRS; developmental disorders
In Japan there are a number of children and adolescents with emotion-related disorders including psychosomatic diseases (orthostatic dysregulation, anorexia nervosa, recurrent pains), behavior problems and school absenteeism. According to our previous report, the Japanese children had significantly higher score of physical symptoms and psychiatric complaints than did the Swedish children, and these were more strongly influenced by school-related stress than by home-related stress. To enforce countermeasures for psychosomatic problems in children, the Japanese Society of Psychosomatic Pediatrics (established in 1982) have started several new projects including multi-center psychosomatic researches and society-based activities. In this article, we present an outline of our study on mental health in Japanese children in comparison with Swedish children. Countermeasures including clinical guidelines for child psychosomatic diseases are reviewed and discussed.
Psychosomatic disease; Orthostatic dysregulation; Anorexia nervosa; School absenteeism; Migraine
The intimate relationship between the urinary and genital systems permits stimuli in one system to influence the other. At least 15 per cent of women with symptoms of cystitis have no organic basis for their complaints. In psychiatric studies it has been noted that sexual conflict is the primary etiological factor in these patients. In some cases, continuance of the disorder leads to irreversible organic change. Urinary symptoms such as frequency, urgency, burning or retention are most common in women and become an automatic response to anxiety-provoking or sexual stimuli.
In men, functional urinary symptoms are relatively infrequent. Often they indicate problems of genital dysfunction. Complaints of impotence, penile pain, testicular pain, or non-specific urethritis stem back to difficulties in their sexual lives. Many of the patients have symptoms of a generalized anxiety tension state due to sexual problems.
A purely organic consideration of genitourinary disorders will lead to erroneous conclusions and unsatisfactory therapeutic results. The psychosomatic approach—that is, considering both physical and psychological aspects—will explain many hitherto difficult cases.
MazeSuite is a complete toolset to prepare, present and analyze navigational and spatial experiments1. MazeSuite can be used to design and edit adapted virtual 3D environments, track a participants' behavioral performance within the virtual environment and synchronize with external devices for physiological and neuroimaging measures, including electroencephalogram and eye tracking.
Functional near-infrared spectroscopy (fNIR) is an optical brain imaging technique that enables continuous, noninvasive, and portable monitoring of changes in cerebral blood oxygenation related to human brain functions2-7. Over the last decade fNIR is used to effectively monitor cognitive tasks such as attention, working memory and problem solving7-11. fNIR can be implemented in the form of a wearable and minimally intrusive device; it has the capacity to monitor brain activity in ecologically valid environments.
Cognitive functions assessed through task performance involve patterns of brain activation of the prefrontal cortex (PFC) that vary from the initial novel task performance, after practice and during retention12. Using positron emission tomography (PET), Van Horn and colleagues found that regional cerebral blood flow was activated in the right frontal lobe during the encoding (i.e., initial naïve performance) of spatial navigation of virtual mazes while there was little to no activation of the frontal regions after practice and during retention tests. Furthermore, the effects of contextual interference, a learning phenomenon related to organization of practice, are evident when individuals acquire multiple tasks under different practice schedules13,14. High contextual interference (random practice schedule) is created when the tasks to be learned are presented in a non-sequential, unpredictable order. Low contextual interference (blocked practice schedule) is created when the tasks to be learned are presented in a predictable order.
Our goal here is twofold: first to illustrate the experimental protocol design process and the use of MazeSuite, and second, to demonstrate the setup and deployment of the fNIR brain activity monitoring system using Cognitive Optical Brain Imaging (COBI) Studio software15. To illustrate our goals, a subsample from a study is reported to show the use of both MazeSuite and COBI Studio in a single experiment. The study involves the assessment of cognitive activity of the PFC during the acquisition and learning of computer maze tasks for blocked and random orders. Two right-handed adults (one male, one female) performed 315 acquisition, 30 retention and 20 transfer trials across four days. Design, implementation, data acquisition and analysis phases of the study were explained with the intention to provide a guideline for future studies.
Transcranial magnetic stimulation (TMS) is a neuropsychiatric tool that can serve as a useful method to better understand the neurobiology of cognitive function, behavior, and emotional processing. The purpose of this paper is to examine the utility of TMS as a means of measuring neocortical function in neuropsychiatric disorders in general, and schizophrenia in particular, for the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) initiative. When incorporating TMS paradigms in research studies, methodological considerations include technical aspects of TMS, cohort selection and confounding factors, and subject safety. Available evidence suggests benefits of TMS alone or in combination with neurophysiologic and neuroimaging methods, including positron emission tomography (PET), single photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), functional MRI (fMRI), functional near infrared spectroscopy (fNIRS), magnetoencephalography (MEG), and electroencephalography (EEG), to explore neocortical function. With the multiple TMS techniques including single-pulse, paired-pulse, paired associative stimulation, and repetitive TMS and theta burst stimulation, combined with neurophysiologic and neuroimaging methods, there exists a plethora of TMS experimental paradigms to modulate different neocortical physiologic processes. Specifically, TMS can measure cortical excitability, intracortical inhibitory and excitatory mechanisms, and local and network cortical plasticity. Coupled with functional and electrophysiological modalities, TMS can provide insight into the mechanisms underlying healthy neurodevelopment and aging, as well as neuropsychiatric pathology. Thus, TMS could be a useful tool in the CNTRICS armamentarium of biomarker methods. Future investigations are warranted to optimize TMS methodologies for this purpose.
Transcranial magnetic stimulation; TMS; schizophrenia; CNTRICS; cortical function; biological marker
Near-infrared spectroscopy has helped our understanding of the neurobiological mechanisms of psychiatric disorders and has advantages including noninvasiveness, lower cost, and ease of use compared with other imaging techniques, like functional magnetic resonance imaging. The verbal fluency task is the most common and well established task used to assess cognitive activation during near-infrared spectroscopy. Recent functional neuroimaging studies have shown that the orbitofrontal cortex and other brain regions, including the dorsolateral prefrontal cortex, may play important roles in the pathophysiology of obsessive-compulsive disorder (OCD). This study aimed to evaluate hemodynamic responses in the dorsolateral prefrontal cortex in patients with OCD using near-infrared spectroscopy during the verbal fluency task and to compare these with dorsolateral prefrontal cortex responses in healthy controls.
Twenty patients with OCD and 20 controls matched for age, gender, handedness, and estimated intelligence quotient participated in this study. The verbal fluency task was used to elicit near-infrared spectroscopic activation and consisted of a 30-second pre-task, followed by three repetitions of a 20-second verbal fluency task (total 60 seconds), followed by a 70-second post-task period. The near-infrared spectroscopy experiment was conducted on the same day as surveys of obsessive-compulsive symptoms, depression, and anxiety. Z-scores for changes in the concentration of oxygenated hemoglobin were compared between the OCD patients and controls in 14 channels set over the left and right dorsolateral prefrontal cortex and frontopolar areas.
During the verbal fluency task, significant task-related activation was detected in both the OCD group and the controls. Changes in oxygenated hemoglobin concentration in the right dorsolateral prefrontal cortex were significantly smaller in the OCD group than in the controls, but were not statistically significant after correction for multiple comparisons.
Patients with OCD have reduced prefrontal, especially right dorsolateral prefrontal, cortical hemodynamic responses as measured by near-infrared spectroscopy during the verbal fluency task. These results support the hypothesis that the dorsolateral prefrontal cortex plays a role in the pathophysiology of OCD.
functional neuroimaging; near-infrared spectroscopy; obsessive-compulsive disorder; prefrontal hemodynamic response; verbal fluency task; dorsolateral prefrontal cortex
To examine the relationship between lifestyles and psychosomatic symptoms in children, we conducted a self-administered questionnaire survey of elementary school students and junior high school students in Japan.
We designed an original questionnaire to investigate the lifestyles and psychosomatic symptoms of children. In 1997, responses to the questionnaires were elicited from public elementary school fourth grade students (then aged 9–10) and public junior high school seventh grade students (then aged 12–13). The survey was repeated annually for three years as the students advanced through school.
For both boys and girls, each cross-sectional analysis revealed a strong relationship between lifestyle behaviors and psychosomatic symptoms. Psychosomatic, symptoms scores varied according to daily hours of sleep, eating of breakfast, having strong likes and dislikes of food, bowel habits, and daily hours of television watching. Both boys and girls with “good” lifestyle, behaviors evaluated by the HPI (Health Practice Index) showed lower scores for psychosomatic symptoms.
These findings show that the lifestyle behaviors of children are significantly associated with psychosomatic symptoms and suggest that poor lifestyle behaviors are likely to increase physical and psychological health risks.
lifestyles; psychosomatic symptoms; elementary school; junior high school; health practice index
Cochlear implants (CI) are commonly used to treat deafness in young children. While many factors influence the ability of a deaf child who is hearing through a CI to develop speech and language skills, an important factor is that the CI has to stimulate the auditory cortex. Obtaining behavioral measurements from young children with CIs can often be unreliable. While a variety of noninvasive techniques can be used for detecting cortical activity in response to auditory stimuli, many have critical limitations when applied to the pediatric CI population. We tested the ability of near-infrared spectroscopy (NIRS) to detect cortical responses to speech stimuli in pediatric CI users. Neuronal activity leads to changes in blood oxy- and de-oxyhemoglobin concentrations that can be detected by measuring the transmission of near-infrared light through the tissue. To verify the efficacy of NIRS, we first compared auditory cortex responses measured with NIRS and fMRI in normal-hearing adults. We then examined four different participant cohorts with NIRS alone. Speech-evoked cortical activity was observed in 100% of normal-hearing adults (11 of 11), 82% of normal-hearing children (9 of 11), 78% of deaf children who have used a CI >4 months (28 of 36), and 78% of deaf children who completed NIRS testing on the day of CI initial activation (7 of 9). Therefore, NIRS can measure cortical responses in pediatric CI users, and has the potential to be a powerful adjunct to current CI assessment tools.
Cochlear implant; NIRS; fMRI; hearing; brain; auditory cortex; speech detection
Measurements of human brain function in children are of increasing interest in cognitive neuroscience. Many techniques for brain mapping used in children, including functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG), magnetoencephalography (MEG) and transcranial magnetic stimulation (TMS), use probes placed on or near the scalp. The distance between the scalp and the brain is a key variable for these techniques because optical, electrical and magnetic signals are attenuated by distance. However, little is known about how scalp-brain distance differs between different cortical regions in children or how it changes with development. We investigated scalp-brain distance in 71 children, from newborn to age 12 years, using structural T1-weighted MRI scans of the whole head. Three-dimensional reconstructions were created from the scalp surface to allow for accurate calculation of brain-scalp distance. Nine brain landmarks in different cortical regions were manually selected in each subject based on the published fNIRS literature. Significant effects were found for age, cortical region and hemisphere. Brain-scalp distances were lowest in young children, and increased with age to up to double the newborn distance. There were also dramatic differences between brain regions, with up to 50% differences between landmarks. In frontal and temporal regions, scalp-brain distances were significantly greater in the right hemisphere than in the left hemisphere. The largest contributors to developmental changes in brain-scalp distance were increases in the corticospinal fluid (CSF) and inner table of the cranium. These results have important implications for functional imaging studies of children: age and brain-region related differences in fNIRS signals could be due to the confounding factor of brain-scalp distance and not true differences in brain activity.
In an evolutionary model, health and disease are regarded as
successful and respectively failed adaptation to the demands of
the environment. The social factors are critical for a
successful adaptation, while emotions are means of both signaling
the organism's state and of adapting the physiological responses
to environmental challenges. Hence the importance of a
biopsychosocial model of health and disease. Psychoemotional
distress generates and/or amplifies somatic symptoms. Somatization may
be viewed as an altered cognitive process, inclining the individual to
an augmented perception of bodily sensations and to an increased degree
of complexity in reporting negative experiences (hence the
greater cognitive effort allocated thereto). Somatosensory
amplification and alexithymia are key elements in this process.
The brain's right hemisphere is more involved in the generation
of emotionally conditioned somatization symptoms. Somatic symptoms
have various psychological and social functions and are strongly
influenced by the particular belief system of the
individual. Inappropriately perceiving the environment as an aggressor
and excessively responding to it (by activating the cytokine system
in correlation with the arousal of the psychic, nervous, and
endocrine systems) may be a key element in the altered cognition
conducive to ill health.
somatoform disorders; unexplained physical symptoms; somatization; amplification; alexithymia; cognitive model; cytokine
Over the last five to ten years there has been an increase in psychosomatic complaints (PSC) in Swedish children. The objective of the study was to examine the relation between PSC and sense of coherence (SOC).
A cross-sectional school survey in the county of Västmanland, Sweden. All 16- and 19-year old adolescents present at school on the day of the survey were asked to complete a questionnaire in their classrooms during a one-lesson hour session under the supervision of their teachers. Totally 3,998 students in both private and public schools, studying in ninth grade elementary school or third grade secondary school participated.
The results from our study show that there is a statistically significant relation between PSC and SOC among adolescents. It also shows that adolescents with a weak SOC score have more symptoms of PSC.
Our study indicates that SOC can help the adolescents to choose a coping strategy that is appropriate for the situation and thereby may prevent them from developing PSC. However, additional studies are needed to confirm our findings.
Children with pervasive developmental disorder (PDD) are thought to have poor imitation abilities. Recently, this characteristic has been suggested to reflect impairments in mirror neuron systems (MNS). We used near-infrared spectroscopy (NIRS) to examine the brain activity of children with PDD during tasks involving imitation and observations of others.
The subjects were 6 male children with PDD (8–14 years old) and 6 age- and gender-matched normal subjects (9–13 years old). A video in which a woman was opening and closing a bottle cap was used as a stimulus. Hemoglobin concentration changes around the posterior part of the inferior frontal gyrus and the adjacent ventral premotor cortex were measured with a 24-channel NIRS machine during action observation and action imitation tasks. Regional oxygenated hemoglobin concentration changes were significantly smaller in the PDD group than in the control group. Moreover, these differences were clearer in the action observation task than in the action imitation task.
Dysfunction in the MNS in children with PDD was suggested by the reduced activation in key MNS regions during tasks involving observations and imitations of others. These preliminary results suggest that further studies are needed to verify MNS dysfunction in children with PDD.
Pervasive developmental disorder; Imitation; Mirror neuron systems; Near-infrared spectroscopy
As a continuation of our earlier work, we present in this study a Kalman filtering based algorithm for the elimination of motion artifacts present in Near Infrared spectroscopy (NIR) measurements. Functional NIR measurements suffer from head motion especially in real world applications where movement cannot be restricted such as studies involving pilots, children, etc. Since head movement can cause fluctuations unrelated to metabolic changes in the blood due to the cognitive activity, removal of these artifacts from NIR signal is necessary for reliable assessment of cognitive activity in the brain for real life applications.
Previously, we had worked on adaptive and Wiener filtering for the cancellation of motion artifacts in NIR studies. Using the same NIR data set we have collected in our previous work where different speed motion artifacts were induced on the NIR measurements we compared the results of the newly proposed Kalman filtering approach with the results of previously studied adaptive and Wiener filtering methods in terms of gains in signal to noise ratio. Here, comparisons are based on paired t-tests where data from eleven subjects are used.
The preliminary results in this current study revealed that the proposed Kalman filtering method provides better estimates in terms of the gain in signal to noise ratio than the classical adaptive filtering approach without the need for additional sensor measurements and results comparable to Wiener filtering but better suitable for real-time applications.
This paper presented a novel approach based on Kalman filtering for motion artifact removal in NIR recordings. The proposed approach provides a suitable solution to the motion artifact removal problem in NIR studies by combining the advantages of the existing adaptive and Wiener filtering methods in one algorithm which allows efficient real time application with no requirement on additional sensor measurements.
Brain microvascular pathology is a common finding in Alzheimer's disease and other dementias. However, the extent to which microvascular abnormalities cause or contribute to cognitive impairment is unclear. Noninvasive near-infrared spectroscopy (NIRS) can address this question, but its use for clarifying the role of microvascular dysfunction in dementia has been limited due to theoretical and practical considerations. We developed a new noninvasive NIRS method to obtain quantitative, dynamic measurements of absolute brain hemoglobin concentration and oxygen saturation and used it to show significant cerebrovascular impairments in a rat model of diet-induced vascular cognitive impairment. We fed young rats folate-deficient (FD) and control diets and measured absolute brain hemoglobin and hemodynamic parameters at rest and during transient mild hypoxia and hypercapnia. With respect to control animals, FD rats featured significantly lower brain hemoglobin concentration (72±4 μmol/L versus 95±6 μmol/L) and oxygen saturation (54%±3% versus 65%±2%). By contrast, resting arterial oxygen saturation was the same for both groups (96%±4%), indicating that decrements in brain hemoglobin oxygenation were independent of blood oxygen carrying capacity. Vasomotor reactivity in response to hypercapnia was also impaired in FD rats. Our results implicate microvascular abnormality and diminished oxygen delivery as a mechanism of cognitive impairment.
aging; capillaries; CBF; NIRS; nutrition; VCI
Cerebral palsy (CP) is the most common motor disorder in children. Currently available neuroimaging techniques require complete body confinement and steadiness and thus are extremely difficult for pediatric patients. Here, we report the use and quantification of functional near infrared spectroscopy (fNIRS) to investigate the functional reorganization of the sensorimotor cortex in children with hemiparetic CP. Ten of sixteen children with congenital hemiparesis were measured during finger tapping tasks and compared with eight of sixteen age-matched healthy children, with an overall measurement success rate of 60%. Spatiotemporal analysis was introduced to quantify the motor activation and brain laterality. Such a quantitative approach reveals a consistent, contralateral motor activation in healthy children at 7 years of age or older. In sharp contrast, children with congenital hemiparesis exhibit all three of contralateral, bilateral and ipsilateral motor activations, depending on specific ages of the pediatric subjects. This study clearly demonstrates the feasibility of fNIRS to be utilized for investigating cortical reorganization in children with CP or other cortical disorders.
Functional near-infrared spectroscopy (fNIRS) is a relatively new technique that can measure hemoglobin changes in brain tissues, and its use in psychiatry has been progressing rapidly. Although it has several disadvantages (e.g., relatively low spatial resolution and the possibility of shallow coverage in the depth of brain regions) compared with other functional neuroimaging techniques (e.g., functional magnetic resonance imaging and positron emission tomography), fNIRS may be a candidate instrument for clinical use in psychiatry, as it can measure brain activity in naturalistic position easily and non-invasively. fNIRS instruments are also small and work silently, and can be moved almost everywhere including schools and care units. Previous fNIRS studies have shown that patients with schizophrenia have impaired activity and characteristic waveform patterns in the prefrontal cortex during the letter version of the verbal fluency task, and part of these results have been approved as one of the Advanced Medical Technologies as an aid for the differential diagnosis of depressive symptoms by the Ministry of Health, Labor and Welfare of Japan in 2009, which was the first such approval in the field of psychiatry. Moreover, previous studies suggest that the activity in the frontopolar prefrontal cortex is associated with their functions in chronic schizophrenia and is its next candidate biomarker. Future studies aimed at exploring fNIRS differences in various clinical stages, longitudinal changes, drug effects, and variations during different task paradigms will be needed to develop more accurate biomarkers that can be used to aid differential diagnosis, the comprehension of the present condition, the prediction of outcome, and the decision regarding treatment options in schizophrenia. Future fNIRS researches will require standardized measurement procedures, probe settings, analytical methods and tools, manuscript description, and database systems in an fNIRS community.
near-infrared spectroscopy; verbal fluency task; biological markers; early intervention; clinical outcome
Background: Autism spectrum disorder (ASD) has been called a “developmental disconnection syndrome,” however the majority of the research examining connectivity in ASD has been conducted exclusively with older children and adults. Yet, prior ASD research suggests that perturbations in neurodevelopmental trajectories begin as early as the first year of life. Prospective longitudinal studies of infants at risk for ASD may provide a window into the emergence of these aberrant patterns of connectivity. The current study employed functional connectivity near-infrared spectroscopy (NIRS) in order to examine the development of intra- and inter-hemispheric functional connectivity in high- and low-risk infants across the first year of life.
Methods: NIRS data were collected from 27 infants at high risk for autism (HRA) and 37 low-risk comparison (LRC) infants who contributed a total of 116 data sets at 3-, 6-, 9-, and 12-months. At each time point, HRA and LRC groups were matched on age, sex, head circumference, and Mullen Scales of Early Learning scores. Regions of interest (ROI) were selected from anterior and posterior locations of each hemisphere. The average time course for each ROI was calculated and correlations for each ROI pair were computed. Differences in functional connectivity were examined in a cross-sectional manner.
Results: At 3-months, HRA infants showed increased overall functional connectivity compared to LRC infants. This was the result of increased connectivity for intra- and inter-hemispheric ROI pairs. No significant differences were found between HRA and LRC infants at 6- and 9-months. However, by 12-months, HRA infants showed decreased connectivity relative to LRC infants.
Conclusions: Our preliminary results suggest that atypical functional connectivity may exist within the first year of life in HRA infants, providing support to the growing body of evidence that aberrant patterns of connectivity may be a potential endophenotype for ASD.
autism; functional connectivity; near-infrared spectroscopy; endophenotype; infancy
Executive function refers to the cognitive processes necessary for goal-directed cognition and behavior, which develop across childhood and adolescence. Recent experimental research indicates that both acute and chronic aerobic exercise promote children’s executive function. Furthermore, there is tentative evidence that not all forms of aerobic exercise benefit executive function equally: Cognitively-engaging exercise appears to have a stronger effect than non-engaging exercise on children’s executive function. This review discusses this evidence as well as the mechanisms that may underlie the association between exercise and executive function. Research from a variety of disciplines is covered, including developmental psychology, kinesiology, cognitive neuroscience, and biopsychology. Finally, these experimental findings are placed within the larger context of known links between action and cognition in infancy and early childhood, and the clinical and practical implications of this research are discussed.
Aerobic Exercise; Physical Activity; Executive Function; Cognition; Infancy/Childhood
This study investigates the neuronal correlates of empathic processing in children aged 4–8 years, an age range discussed to be crucial for the development of empathy. Empathy, defined as the ability to understand and share another person's inner life, consists of two components: affective (emotion-sharing) and cognitive empathy (Theory of Mind). We examined the hemodynamic responses of preschool and school children (N = 48), while they processed verbal (auditory) and non-verbal (cartoons) empathy stories in a passive following paradigm, using functional Near-Infrared Spectroscopy. To control for the two types of empathy, children were presented blocks of stories eliciting either affective or cognitive empathy, or neutral scenes which relied on the understanding of physical causalities. By contrasting the activations of the younger and older children, we expected to observe developmental changes in brain activations when children process stories eliciting empathy in either stimulus modality toward a greater involvement of anterior frontal brain regions. Our results indicate that children's processing of stories eliciting affective and cognitive empathy is associated with medial and bilateral orbitofrontal cortex (OFC) activation. In contrast to what is known from studies using adult participants, no additional recruitment of posterior brain regions was observed, often associated with the processing of stories eliciting empathy. Developmental changes were found only for stories eliciting affective empathy with increased activation, in older children, in medial OFC, left inferior frontal gyrus, and the left dorsolateral prefrontal cortex. Activations for the two modalities differ only little, with non-verbal presentation of the stimuli having a greater impact on empathy processing in children, showing more similarities to adult processing than the verbal one. This might be caused by the fact that non-verbal processing develops earlier in life and is more familiar.
OFC; cognitive empathy; affective empathy; children; fNIRS; verbal; non-verbal
Functional neuroimaging and related neuroimaging techniques are becoming important tools for rehabilitation research. Functional neuroimaging techniques can be used to determine the effects of brain injury or disease on brain systems related to cognition and behavior and to determine how rehabilitation changes brain systems. These techniques include: functional magnetic resonance imaging (fMRI), positron emission tomography (PET), electroencephalography (EEG), magnetoencephalography (MEG), near infrared spectroscopy (NIRS), and transcranial magnetic stimulation (TMS). Related diffusion weighted magnetic resonance imaging techniques (DWI), including diffusion tensor imaging (DTI) and high angular resolution diffusion imaging (HARDI), can quantify white matter integrity. With the proliferation of these imaging techniques in rehabilitation research, it is critical that rehabilitation researchers, as well as consumers of rehabilitation research, become familiar with neuroimaging techniques, what they can offer, and their strengths and weaknesses The purpose to this review is to provide such an introduction to these neuroimaging techniques.
The aims of the present study are to investigate whether there are differences in health-related quality of life (HRQoL) between girls and boys in two different age groups, to study how much of children’s variance in HRQoL can be explained by common psychosomatic health symptoms, and to examine whether the same set of psychosomatic symptoms can explain differences in HRQoL, both between girls and boys and between older and younger school children.
A cross-sectional study was conducted of 253 children, 99 of ages 11–12 years (n=51 girls, n=48 boys) and 154 of ages 15–16 years (n=82 girls, n=72 boys), in Swedish schools. The KIDSCREEN-52 instrument, which covers 10 dimensions of HRQoL and additional questions about psychosomatic health symptoms, were used. Analyses of variance were conducted to investigate differences between the genders and age groups, and in interaction effects on the KIDSCREEN-52 dimensions. Regression analyses were used to investigate the impacts of psychosomatic symptoms on gender and age group differences in HRQoL.
Boys rated themselves higher than girls on the KIDSCREEN dimensions: physical and psychological well-being, moods and emotions, self-perception, and autonomy. Main effects of age group were found for physical well-being, psychological well-being, moods and emotions, self-perception, autonomy, and school environment, where younger children rated their HRQoL more highly than those aged 15–16 years. Girls rated their moods and emotions dramatically lower than boys in the older age group, but the ratings of emotional status were more similar between genders at younger ages. Psychosomatic symptoms explained between 27% and 50% of the variance in the children’s HRQoL. Sleeping difficulties were a common problem for both girls and boys. Depression and concentration difficulties were particularly associated with HRQoL among girls whereas stomach aches were associated with HRQoL among boys.
Girls and adolescents experience poorer HRQoL than boys and younger children, but having psychosomatic symptoms seem to explain a substantial part of the variation. Strategies to promote health among school children, in particular to alleviate sleep problems among all children, depression and concentration difficulties among girls, and stomach aches among boys, are of great importance.
Health; Quality of life; Gender; School; Children; Adolescents; Psychosomatic symptoms; Sleep problems; KIDSCREEN
Functional neuroimaging techniques such as functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS) can be used to isolate an evoked response to a stimulus from significant background physiological fluctuations. Data analysis approaches typically use averaging or linear regression to remove this physiological baseline with varying degrees of success. Biophysical model-based analysis of the functional hemodynamic response has also been advanced previously with the Balloon and Windkessel models. In the present work, a biophysical model of systemic and cerebral circulation and gas exchange is applied to resting state NIRS neuroimaging data from 10 human subjects. The model further includes dynamic cerebral autoregulation, which modulates the cerebral arteriole compliance to control cerebral blood flow. This biophysical model allows for prediction, from noninvasive blood pressure measurements, of the background hemodynamic fluctuations in the systemic and cerebral circulations. Significantly higher correlations with the NIRS data were found using the biophysical model predictions compared to blood pressure regression and compared to transfer function analysis (multifactor ANOVA, p<0.0001). This finding supports the further development and use of biophysical models for removing baseline activity in functional neuroimaging analysis. Future extensions of this work could model changes in cerebrovascular physiology that occur during development, aging and disease.
Physiological modeling; dynamic cerebral autoregulation; NIRS; fMRI; Balloon model; Windkessel
Deficits in brain networks that support cognitive regulatory functions are prevalent in many psychiatric disorders. Findings across neuropsychology and neuroimaging point to broad-based impairments that cross traditional diagnostic boundaries. These dysfunctions are largely separate from the classical symptoms of the disorders, and manifest in regulatory problems in both traditional cognitive and emotional domains. As such, they relate to the capacity of patients to engage effectively in their daily lives and activity, often persist even in the face of symptomatically effective treatment, and are poorly targeted by current treatments. Advances in cognitive neuroscience now allow us to ground an understanding of these cognitive regulatory deficits in the function and interaction of key brain networks. This emerging neurobiological understanding furthermore points to several promising routes for novel neuroscience-informed treatments targeted more specifically at improving cognitive function in a range of psychiatric disorders.
amygdala; anxiety; bipolar; cingulate; default mode; depression; emotion regulation; executive function; prefrontal; schizophrenia
The last decade has witnessed an explosion of research into the neural mechanisms underlying emotion processing on the one hand, and cognitive control and executive function on the other hand. More recently, studies have begun to directly examine how concurrent emotion processing influences cognitive control performance but many questions remain currently unresolved. Interestingly, parallel to investigations in healthy adults, research in developmental cognitive neuroscience and developmental affective disorders has provided some intriguing findings that complement the adult literature. This review provides an overview of current research on cognitive control and emotion interactions. It integrates parallel lines of research in adulthood and development and will draw on several lines of evidence ranging from behavioral, neurophysiological, and neuroimaging work in healthy adults and extend these to work in pediatric development and patients with affective disorders. Particular emphasis is given to studies that provide information on the neurobiological underpinnings of emotional and cognitive control processes using functional magnetic resonance imaging. The findings are then summarized and discussed in relation to neurochemical processes and the dopamine hypothesis of prefrontal cortical function. Finally, open areas of research for future study are identified and discussed within the context of cognitive control emotion interactions.
review; emotion cognitive control interaction; development; anxiety; depression
Functional near infrared spectroscopy (fNIRS) is a non-invasive, safe, and portable optical neuroimaging method that can be used to assess brain dynamics during skill acquisition and performance of complex work and everyday tasks. In this paper we describe neuroergonomic studies that illustrate the use of fNIRS in the examination of training-related brain dynamics and human performance assessment. We describe results of studies investigating cognitive workload in air traffic controllers, acquisition of dual verbal-spatial working memory skill, and development of expertise in piloting unmanned vehicles. These studies used conventional fNIRS devices in which the participants were tethered to the device while seated at a workstation. Consistent with the aims of mobile brain imaging (MoBI), we also describe a compact and battery-operated wireless fNIRS system that performs with similar accuracy as other established fNIRS devices. Our results indicate that both wired and wireless fNIRS systems allow for the examination of brain function in naturalistic settings, and thus are suitable for reliable human performance monitoring and training assessment.
fNIRS; optical brain monitoring; working memory training; prefrontal cortex; hemodynamic response; wireless NIRS