Left Temporal Activation Research Articles

Analysis of definite awake bruxism using a portable electromyography device.

This study aimed to compare awake bruxism events between subjective and objective evaluations using a questionnaire survey and a modified portable electromyography (EMG) device, and to examine correlations between sleep quality and awake bruxism. The Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and awareness of awake bruxism as clarified via interviews were conducted on 34 participants as subjective evaluations. The EMG device was used to record left temporal muscle activity for 6.5 h (from 09:00 to 15:30) and the number of awake bruxism episodes per hour. The participants were then classified into "bruxer" and "non-bruxer" groups based on the number of awake bruxism episodes. The mean number of awake bruxism episodes per hour was 33.6 ± 21.4, and 23% of the participants who reported having no awareness of awake bruxism in the interviews were defined as "bruxers" in the objective evaluations. In the bruxer group, positive correlations were found between the number of awake bruxism episodes and both ESS and PSQI scores. These findings suggest that objective measurements using a portable EMG device can increase the diagnostic accuracy for awake bruxism, and that sleep quality is a major risk factor for awake bruxism.

A longitudinal study of the task‐related activation trajectory in people with mild cognitive impairment and subjective cognitive decline

AbstractBackgroundBrain hyperactivation — defined as higher level of activation compared to controls — was suggested as a very early signature of prodromal Alzheimer’s disease (AD), which would gradually decrease with progression to dementia. Longitudinal studies with people who have mild cognitive impairment (MCI) and subjective cognitive decline (SCD) can be used to capture the temporal dynamics and inter‐individual differences of these very early activation changes. Here, we aimed to identify the temporal trajectory of task‐related activation in participants with SCD and MCI from the CIMA‐Q cohort, which has data collected at multiple time‐points. We thus identified subgroups based on their common activation trajectory and characterized subgroups defined from the activation trajectory.MethodThe study included 53 older participants (40 SCD; 13 MCI) from the CIMA‐Q cohort with neuroimaging data collected over at least two time‐points (66‐85 years old; 36 women, 17 men). An fMRI examination was done every two years (2‐4 time‐points; average follow‐up: 3.2 years). Task‐related activation was measured during an associative memory encoding task. Group‐based trajectory models were estimated to identify homogeneous groups of participants based on activation trajectories in the hippocampus and in regions from the cortical signature of AD. Groups defined based on activation trajectories were then compared using Apolipoprotein‐ε4 (ApoE4), baseline cognition and hippocampal volume.ResultTwo different trajectories of activation were identified: Trajectory 1 was found in several cortical regions and was characterized by a high level of initial activation, which decreased over time. Trajectory 2 was characterized by a lower activation level, which remained stable over time or increased slightly on time‐point 4. Smaller hippocampal volume and ApoE4 were associated with Trajectory 1 for the left angular gyrus, and left hippocampal and right middle temporal gyrus activation, respectively.ConclusionAn inverted U‐shape trajectory was found with high activation followed by gradually decreasing activation in AD‐signature regions. This trajectory was associated with smaller hippocampal volume and/or the presence of ApoE4 allele, both of which are biomarkers that increase the likelihood of developing AD. This finding supports the hypothesis that the inverted U‐shape trajectory of hyperactivation could be an index of prodromal AD.

Glycemic control level alters working memory neural dynamics in adults with type 2 diabetes.

Poor glycemic control in type 2 diabetes has been associated with accentuated age-related cognitive decline, although the underlying neural mechanisms are not well understood. The current study sought to identify the impact of glycemic control on the neural dynamics serving working memory in adults with type 2 diabetes. Participants (n = 34, ages = 55-73) performed a working memory task while undergoing MEG. Significant neural responses were examined relative to poorer (A1c > 7.0%) or tighter glycemic control (A1c < 7.0%). Those with poorer glycemic control showed diminished responses within left temporal and prefrontal regions during encoding and showed diminished responses within right occipital cortex during maintenance but showed an enhanced activity in the left temporal, occipital, and cerebellar regions during maintenance. Notably, left temporal activity in encoding and left lateral occipital activity in maintenance significantly predicted performance on the task such that diminished temporal activity led to longer reaction times, which were driven by the poorer glycemic control group. Greater lateral occipital activity during maintenance was associated with both lower accuracy and longer reaction times across all participants. These findings suggest that glycemic control has a robust impact on the neural dynamics serving working memory, with distinct effects by subprocess (e.g. encoding vs. maintenance) and direct effects on behavior.

Psychiatric symptoms in autoimmune encephalitis. A case report

IntroductionEarly stages of autoimmune encefalitis (AE) often present cognitive and neuropsychiatric symptoms such as personality change, irritability, axiety, depression, behavioral disorders, hallucinations, disorientation, sleep-wake cycle reversals, …). Thus often these cases are first treated as psychiatric disorders.ObjectivesA literature review throughout a case report presentation.MethodsWe present the case of a 25-year old female with a medical history of iron-deficiency anemia who arrives at the emergency service. She presents the following one week of evolution clinical picture: complex auditive hallucinations, behavioral disturbances, sleep disorder and short term memory impairment. Neurological examination, LP and craneal CT are all normal. CSF analysis has no abnormalities. Thus she entered the psychiatric ward. There she was treated with neuroleptics with no improvement of symptoms presenting a severe psychomotor agitation and language impairment. After neurology interconsultation AE is suspected.ResultsShe was performed an EEG (left temporal epileptiform activity), CSF (inflammatory pattern), MRI (bilateral temporal lobe hyperintensity). Suspecting limbic encephalitis the presence of anti-NMDAR antibodies was tested , which turned out to be positive. First she was treated with corticotherapy with mild results. Then she was treated with intravenous immunoglobulin improving significantly.ConclusionsAnti-NMDAR encephalitis is usually a multistage illness. Early in the course of disease psychiatric manifestations are not rare. Therefore the proper diagnosis and approach of AE may requiere a highly organized assessment, starting with detailed history and physical examination and an appropriate testing to exclude other possible relevant pathologies.DisclosureNo significant relationships.

Case Report: Multisystem Autoimmune and Overlapping GAD65-Antibody-Associated Neurological Disorders With Beneficial Effect of Epilepsy Surgery and Rituximab Treatment

Glutamic acid decarboxylase (GAD) antibodies are associated with disabling conditions such as stiff person syndrome, temporal lobe epilepsy (TLE), limbic encephalitis, cerebellar ataxia (CA), and ocular movement disorders, which are usually chronic and difficult to treat. GAD-related TLE has poor response to anti-seizure medications and immune therapies, and epilepsy surgery is rarely successful. We report on a 47-year-old female with history of migraine, autoimmune thyroid disease, ankylosing spondylitis, and drug-resistant TLE. A video electroencephalography recorded frequent seizures with temporo-insular semiology, correlating to left temporal epileptiform activity and left mesiotemporal hyperintensity on magnetic resonance imaging. GAD autoimmunity was confirmed by very high GAD antibody titers in serum and cerebrospinal fluid. Steroids, immunoglobulins, and cyclophosphamide had no effect, and selective left amygdalectomy was performed based on very restricted hypermetabolism on positron-emission tomography. After transient seizure freedom, significant epilepsy improvement was observed in spite of memory decline. Transient worsening was noted 1 year later during diabetes mellitus manifestation and 5 years later during presentation of progressive CA, which stabilized on rituximab treatment. We believe this case illustrates the diversity and the frequent overlap of GAD-associated disorders, the need of early and aggressive immunotherapy in severe patients, as well as the possible benefit from epilepsy surgery in some GAD-TLE.

Distributed Subnetworks of Depression Defined by Direct Intracranial Neurophysiology.

Major depressive disorder is a common and disabling disorder with high rates of treatment resistance. Evidence suggests it is characterized by distributed network dysfunction that may be variable across patients, challenging the identification of quantitative biological substrates. We carried out this study to determine whether application of a novel computational approach to a large sample of high spatiotemporal resolution direct neural recordings in humans could unlock the functional organization and coordinated activity patterns of depression networks. This group level analysis of depression networks from heterogenous intracranial recordings was possible due to application of a correlational model-based method for inferring whole-brain neural activity. We then applied a network framework to discover brain dynamics across this model that could classify depression. We found a highly distributed pattern of neural activity and connectivity across cortical and subcortical structures that was present in the majority of depressed subjects. Furthermore, we found that this depression signature consisted of two subnetworks across individuals. The first was characterized by left temporal lobe hypoconnectivity and pathological beta activity. The second was characterized by a hypoactive, but hyperconnected left frontal cortex. These findings have applications toward personalization of therapy.

Exploring the Brain Activity Related to Missing Penalty Kicks: An fNIRS Study

At vital moments in professional soccer matches, penalties were often missed. Psychological factors, such as anxiety and pressure, are among the critical causes of the mistakes, commonly known aschoking under pressure. Nevertheless, the factors have not been fully explored. In this study, we used functional near-infrared spectroscopy (fNIRS) to investigate the influence of the brain on this process. Anin-situstudy was set-up (N= 22), in which each participant took 15 penalties under three different pressure conditions: without a goalkeeper, with an amiable goalkeeper, and with a competitive goalkeeper. Both experienced and inexperienced soccer players were recruited, and the brain activation was compared across groups. Besides, fNIRS activation was compared between sessions that participants felt anxious against sessions without anxiety report, and between penalty-scoring and -missing sessions. The results show that the task-relevant brain region, the motor cortex, was more activated when players were not experiencing performance anxiety. The activation of task-irrelevant areas was shown to be related to players experiencing anxiety and missing penalties, especially the prefrontal cortex (PFC). More particularly, an overall higher activation of the PFC and an increase of PFC lateral asymmetry were related to anxious players and missed penalties, which can be caused by players' worries about the consequences of scoring or missing the penalty kicks. When experienced players were feeling anxious, their left temporal cortex activation increased, which could be an indication that experienced overthink the situation and neglect their automated skills. Besides, the left temporal cortex activation is higher when inexperienced players succeeded to score a penalty. Overall, the results of this study are in line with the neural efficiency theory and demonstrate the feasibility and ecological validity to detect neurological clues relevant to anxiety and performance from fNIRS recordingsin the field.

All talk? Challenging the use of left-temporal EEG alpha oscillations as valid measures of verbal processing and conscious motor control

This study tested the validity of EEG left-temporal alpha power and upper-alpha T7-Fz connectivity as indices of verbal activity and conscious motor control. Participants (n = 20) reached for, and transported, a jar under three conditions: a control condition and two self-talk conditions aimed at eliciting either task-unrelated verbal processing or task-related conscious control, while EEG and hand kinematics were recorded. Compared to the control condition, both self-talk conditions increased self-reported verbal processing, but only the task-related self-talk condition increased left-temporal activity (i.e., alpha power decreased). However, as cortical activity increased across the entire scalp topography, conscious control likely elicits a multitude of processes that may not be explained by left-temporal activity or verbal processing alone, but by a widespread decrease in neural efficiency. No significant effects for T7-Fz connectivity were detected. Results suggest that left-temporal EEG alpha oscillations are unlikely to uniquely reflect verbal processing during conscious motor control.

Identifying the neural basis of a language-impaired phenotype of temporal lobe epilepsy.

To identify neuroimaging and clinical biomarkers associated with a language-impaired phenotype in refractory temporal lobe epilepsy (TLE). Eighty-five patients with TLE were characterized as language-impaired (TLE-LI) or non-language-impaired (TLE-NLI) based on comprehensive neuropsychological testing. Structural magnetic resonance imaging (MRI), diffusion tensor imaging, and functional MRI (fMRI) were obtained in patients and 47 healthy controls (HC). fMRI activations and cortical thickness were calculated within language regions of interest, and fractional anisotropy (FA) was calculated within deep white matter tracts associated with language. Analyses of variance were performed to test for differences among the groups in imaging measures. Receiver operator characteristic curves were used to determine how well different clinical versus imaging measures discriminated TLE-LI from TLE-NLI. TLE-LI patients showed significantly less activation within left superior temporal cortex compared to HC and TLE-NLI, regardless of side of seizure onset. TLE-LI also showed decreased FA in the inferior longitudinal fasciculus and arcuate fasciculus compared to HC. Cortical thickness did not differ between groups in any region. A model that included language-related fMRI activations within the superior temporal gyrus, age at onset, and demographic variables was the most predictive of language impairment (area under the curve = 0.80). These findings demonstrate a unique imaging signature associated with a language-impaired phenotype in TLE, characterized by functional and microstructural alterations within the language network. Reduced left superior temporal activation combined with compromise to language association tracts underlies this phenotype, extending our previous work on cognitive phenotypes that could have implications for treatment-planning or cognitive progression in TLE.

Neurocognitive correlates of category ambiguous verb processing: The single versus dual lexical entry hypotheses

Word-class ambiguous words engender greater processing time and fMRI (BOLD signal) activation than unambiguous ones. Theoretical accounts of this phenomenon suggest that words with multiple meanings (1) are associated with multiple lexical entries and thus require greater selection demands, or (2) undergo computationally expensive grammatical processes that convert words from one word-class to another. Using an fMRI grammaticality judgment task, we tested these accounts by examining word-class ambiguous polysemic (e.g., brush) and homonymic (e.g., bear) verbs, and unambiguous verbs (e.g., bake). Results showed that ambiguous verbs evoked longer response times and greater neural activation in the left inferior frontal and parietal gyri. However, homonymic verbs also showed increased left inferior frontal and temporal neural activations compared to polysemic verbs. This indicates that rather than having multiple lexical representations like homonyms, polysemic verbs may share a core representation with their noun counterparts.

Neural correlates of word learning in children

Memory representations of words are thought to undergo changes with consolidation: Episodic memories of novel words are transformed into lexical representations that interact with other words in the mental dictionary. Behavioral studies have shown that this lexical integration process is enhanced when there is more time for consolidation. Neuroimaging studies have further revealed that novel word representations are initially represented in a hippocampally-centered system, whereas left posterior middle temporal cortex activation increases with lexicalization. In this study, we measured behavioral and brain responses to newly-learned words in children. Two groups of Dutch children, aged between 8–10 and 14–16 years, were trained on 30 novel Japanese words depicting novel concepts. Children were tested on word-forms, word-meanings, and the novel words’ influence on existing word processing immediately after training, and again after a week. In line with the adult findings, hippocampal involvement decreased with time. Lexical integration, however, was not observed immediately or after a week, neither behaviorally nor neurally. It appears that time alone is not always sufficient for lexical integration to occur. We suggest that other factors (e.g., the novelty of the concepts and familiarity with the language the words are derived from) might also influence the integration process.

Composing lexical versus functional adjectives: Evidence for uniformity in the left temporal lobe.

Featural information (e.g., color or shape) allows interlocutors to focus their attention on the specific items under discussion from the vast set of possibilities in the environment. Intriguingly, when they are used to modify and restrict nouns, adjectives can either carry featural information themselves (e.g., green car) or retrieve featural information from the context (e.g., somebody points at a car and claims that she has the same car or a different car). Do the processing of same/different car and green car share neural correlates? For the composition of nouns with feature-carrying adjectives, prior work revealed early compositional effects (roughly 200 ms after noun onset) in the left anterior temporal lobe. However, although we know that such effects do not extend to cases of numeral quantification, which add no conceptual features to the noun (e.g., two boats), we do not know whether they extend to functional adjectives that themselves introduce no features, but instead reference features in the context. To address this question, we measured magnetoencephalography (MEG) during the processing of five types of noun phrases (NPs): same NPs (e.g., same star), different NPs (e.g., different star), color NPs (e.g., green star), comparative NPs (e.g., larger star), and another NPs (e.g., another star). Our main finding was that between 185 to 240 ms after noun onset, same and different NPs patterned with the color NPs in their elicited left temporal lobe activity, and same NPs even trended toward higher amplitudes than the color NPs. This shows that the mechanism driving combinatory effects in the left temporal cortex does not require the input words to directly name conceptual features, as long as the words reference featural information in the context, and that overlapping neural correlates underlie the composition of featural information from both linguistic and nonlinguistic sources.

The neural correlates of mental arithmetic in adolescents: a longitudinal fNIRS study

BackgroundArithmetic processing in adults is known to rely on a frontal-parietal network. However, neurocognitive research focusing on the neural and behavioral correlates of arithmetic development has been scarce, even though the acquisition of arithmetic skills is accompanied by changes within the fronto-parietal network of the developing brain. Furthermore, experimental procedures are typically adjusted to constraints of functional magnetic resonance imaging, which may not reflect natural settings in which children and adolescents actually perform arithmetic. Therefore, we investigated the longitudinal neurocognitive development of processes involved in performing the four basic arithmetic operations in 19 adolescents. By using functional near-infrared spectroscopy, we were able to use an ecologically valid task, i.e., a written production paradigm.ResultsA common pattern of activation in the bilateral fronto-parietal network for arithmetic processing was found for all basic arithmetic operations. Moreover, evidence was obtained for decreasing activation during subtraction over the course of 1 year in middle and inferior frontal gyri, and increased activation during addition and multiplication in angular and middle temporal gyri. In the self-paced block design, parietal activation in multiplication and left angular and temporal activation in addition were observed to be higher for simple than for complex blocks, reflecting an inverse effect of arithmetic complexity.ConclusionsIn general, the findings suggest that the brain network for arithmetic processing is already established in 12–14 year-old adolescents, but still undergoes developmental changes.

An fMRI study on the processing of long-distance wh-movement in a second language

Recent behavioural evidence from second language (L2) learners has suggested native-like processing of syntactic structures, such as long-distance wh-dependencies in L2. The underlying processes are still largely debated, while the available neuroimaging evidence has been restricted to native (L1) processing. Here we test highly proficient L2 learners of English in an fMRI experiment incorporating a sentence reading task with long-distance wh-dependencies, including abstract syntactic categories (empty traces of wh-movement). Our results suggest that long-distance wh-dependencies impose increased working memory (WM) demands, compared to control sentences of equal length, demonstrated as increased activation of the superior and middle temporal gyri bilaterally. Additionally, our results suggest abstract syntactic processing by the most immersed L2 learners, manifested as comparable left temporal activity for sentences with wh-traces and sentences with no wh-movement. These findings are discussed against current theoretical proposals about L2 syntactic processing.

Atypical activation of action-semantic network in adolescents with autism spectrum disorder

In typical adults, fMRI studies have shown activation of primary and pre-motor regions during action word processing. Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments. ASD studies have shown atypical semantic processing and motor deficits. The objective of this study was to examine semantic processing of verbs in ASD. 15 ASD adolescents and 19 typically developing adolescents, 11–16years, completed a semantic similarity judgment task during fMRI. There were no differences in task accuracy or reaction time. At the group level, both groups had activation in left language areas; controls, but not ASD, also had activation in the left pre-supplementary motor area (pre-SMA). In ASD, less left frontal activation and reduced left lateralization of activation within these regions was associated with shorter reaction times and better language skills. More left temporal activation was associated with better language abilities in ASD. Differences in pre-SMA activation may relate to motor planning deficits or differences in approach to the semantic task in ASD. Results suggest that left frontal language areas may be less efficient in ASD and those who can compensate by recruiting more right hemisphere homologues may result in better language abilities.

Effect of essential oil and supercritical carbon dioxide extract from the root of Angelica gigas on human EEG activity

ObjectivesThe present study aimed to investigate the effect of inhalation of essential oil (EO) and supercritical carbon dioxide extract (SC-CO2) from the root of A. gigas on human electroencephalographic (EEG) activity. Materials and methodsFor this purpose, the EO was obtained from the root of A. gigas by steam distillation and SC-CO2 was obtained at 50 °C and 400 bar for 1 h. The EEG readings were recorded using the QEEG-8 system from 8 electrode sites according to the International 10-20 system. ResultsIn the EEG study, the absolute low beta (left temporal and left parietal) activity significantly increased during the inhalation of EO. In the case of SC-CO2 inhalation, there was no significant change in absolute waves. ConclusionThe results revealed that the EO of A. gigas root produced significant changes in the absolute low beta activity and these changes may enhance the language learning abilities of human brain.

The role of emotional inhibitory control in specific internet addiction – an fMRI study

BackgroundAddicts to specific internet applications involving communication features showed increased social anxiety, emotional competence deficits and impaired prefrontal-related inhibitory control. The dorsal Anterior Cingulate Cortex (dACC) likely plays an important role in cognitive control and negative affect (such as social exclusion, pain or anxiety). AimTo assess (social) anxiety-related inhibitory control in specific internet addiction (addicted use of games and social networks) and its relation to altered dACC activation. MethodsN=44 controls and n=51 specific internet addicts completed an anxious words-based Affective Go/No-Go task (AGN). A subsample of n=23 healthy controls and n=25 specific internet addicts underwent functional Magnetic Resonance Imaging (fMRI) while completing an Emotional Stroop Task (EST) with socially anxious, positive, negative and neutral words. Subgroups of internet gaming and social network addicts were exploratively assessed. Psychometric measures of social anxiety, emotional competence and impulsivity were additionally explored. ResultsSpecific internet addicts showed higher impulsivity, social anxiety and reduced emotional competence. Between-group differences in AGN and EST behavioral measures were not detected. No group differences were found in the dACC, but explorative analyses revealed decreased left middle and superior temporal gyrus activation during interference of socially anxious words in internet gaming and relative to social network addicts. ConclusionGiven the function of the left middle temporal gyrus in the retrieval of words or expressions during communication, our findings give a first hint that social words might be less retrievable in the semantic storage of internet gaming addicts, possibly indicating deficiencies in handling speech in social situations.

Word and object recognition during reading acquisition: MEG evidence

Studies on adults suggest that reading-induced brain changes might not be limited to linguistic processes. It is still unclear whether these results can be generalized to reading development. The present study shows to which extent neural responses to verbal and nonverbal stimuli are reorganized while children learn to read. MEG data of thirty Basque children (4–8y) were collected while they were presented with written words, spoken words and visual objects. The evoked fields elicited by the experimental stimuli were compared to their scrambled counterparts. Visual words elicited left posterior (200–300ms) and temporal activations (400–800ms). The size of these effects increased as reading performance improved, suggesting a reorganization of children’s visual word responses. Spoken words elicited greater left temporal responses relative to scrambles (300–700ms). No evidence for the influence of reading expertise was observed. Brain responses to objects were greater than to scrambles in bilateral posterior regions (200–500ms). There was a greater left hemisphere involvement as reading errors decreased, suggesting a strengthened verbal decoding of visual configurations with reading acquisition. The present results reveal that learning to read not only influences written word processing, but also affects visual object recognition, suggesting a non-language specific impact of reading on children’s neural mechanisms.

Functional Changes in the Language Network in Response to Increased Amyloid β Deposition in Cognitively Intact Older Adults.

Word finding symptoms are frequent early in the course of Alzheimer’s disease and relate principally to functional changes in left posterior temporal cortex. In cognitively intact older adults, we examined whether amyloid load affects the network for language and associative-semantic processing. Fifty-six community-recruited subjects (52–74 years), stratified for apolipoprotein E and brain-derived neurotrophic factor genotype, received a neurolinguistic assessment, 18 F-flutemetamol positron emission tomography, and afunctional MRI of the associative-semantic system. The primary measure of amyloid load was the cerebral-to-cerebellar gray matter standardized uptake value ratio in a composite cortical volume of interest (SUVRcomp). The primary outcome analysis consisted of a whole-brain voxelwise linear regression between SUVRcomp and fMRI responseduringassociative-semantic versusvisuoperceptualprocessing.Higheractivityin oneregion,theposteriorleftmiddle temporal gyrus, correlated positively with increased amyloid load. The correlation remained significant when only the word conditions were contrasted but not for pictures. According to a stepwise linear regression analysis, offline naming reaction times correlated positively with SUVRcomp. A binary classification into amyloid-positive and amyloid-negative cases confirmed our findings. The left posterior temporal activity increase may reflect higher demands for semantic control in the presence of a higher amyloid burden.

Decreased sleep duration is associated with increased fMRI responses to emotional faces in children

In adults and children, sleep loss is associated with affective dysregulation and increased responsivity to negative stimuli. Adult functional neuroimaging (fMRI) studies have demonstrated associations between restricted sleep and neural alterations in the amygdala and reward circuitry when viewing emotional picture and face stimuli. Despite this, few studies have examined the associations between short sleep duration and emotional responsivity in typically developing children, and no studies have investigated this relationship using fMRI. The current study examined the relationship between sleep duration and fMRI activation to emotional facial expressions in 15 male children (ages 7–11 years). During fMRI scanning, subjects viewed and made perceptual judgments regarding negative, neutral, and positive emotional faces. Maternal reported child sleep duration was negatively associated with (a) activation in the bilateral amygdala, left insula, and left temporal pole activation when viewing negative (i.e., fearful, disgust) vs. neutral faces, (b) right orbitofrontal and bilateral prefrontal activation when viewing disgust vs. neutral faces, and (c) bilateral orbitofrontal, right anterior cingulate, and left amygdala activation when viewing happy vs. neutral faces. Consistent with our prediction, we also noted that emotion-dependent functional connectivity between the bilateral amygdala and prefrontal cortex, cingulate, fusiform, and occipital cortex was positively associated with sleep duration. Paralleling similar studies in adults, these findings collectively suggest that decreased sleep duration in school-aged children may contribute to enhanced reactivity of brain regions involved in emotion and reward processing, as well as decreased emotion-dependent functional connectivity between the amygdala and brain regions associated with emotion regulation.