Longitudinal associations between resting-state, interregional theta-beta phase-amplitude coupling and cognition in 12-15-year-old adolescents.

Some researchers theorize that musicians’ greater language ability is mediated by greater working memory because music and language share the same processing resources. Prior work using working memory sentence processing dual-task paradigms have shown that holding verbal information (e.g., words) in working memory interferes with sentence processing. In contrast, visuospatial stimuli are processed in a different working memory store and should not interfere with sentence processing. We tested whether music showed similar interference to sentence processing as opposed to noninterference like visuospatial stimuli. We also compared musicians to nonmusicians to investigate whether musical training improves verbal working memory. Findings revealed that musical stimuli produced similar working memory interference as linguistic stimuli, but visuospatial stimuli did not—suggesting that music and language rely on similar working memory resources (i.e., verbal skills) that are distinct from visuospatial skills. Musicians performed more accurately on the working memory tasks, particularly for the verbal and musical working memory stimuli, supporting an association between musicianship and greater verbal working memory capacity. Future research is necessary to evaluate the role of music training as a cognitive intervention or educational strategy to enhance reading fluency.

FIGURE 1. The Atkinson and Shiffrin Model of memory is diagramed in the gray panel. Sensory information is perceived and suppressed via selective attention processes, then briefly held in the limited-capacity modality-specific sensory register. Information enhanced by selective attention enters into short term memory (STM). The process of rehearsal (maintenance) can sustain information in STM. Information in STM is automatically encoded (stored, consolidated) into long term memory (LTM). Although flawed, this model continues to provide a simple and easy approach to understanding memory. Assumptions that proved to be inconsistent with research included that any information in STM will transfer to LTM and that STM is required

SUMMARYNeuronal oscillations are suggested to play an important role in auditory working memory (WM), but their contribution to content-specific representations has remained unclear. Here, we measure magnetoencephalography during a retro-cueing task with parametric ripple-sound stimuli, which are spectrotemporally similar to speech but resist non-auditory memory strategies. Using machine learning analyses, with rigorous between-subject cross-validation and non-parametric permutation testing, we show that memorized sound content is strongly represented in phase-synchronization patterns between subregions of auditory and frontoparietal cortices. These phase-synchronization patterns predict the memorized sound content steadily across the studied maintenance period. In addition to connectivity-based representations, there are indices of more local, “activity silent” representations in auditory cortices, where the decoding accuracy of WM content significantly increases after task-irrelevant “impulse stimuli.” Our results demonstrate that synchronization patterns across auditory sensory and association areas orchestrate neuronal coding of auditory WM content. This connectivity-based coding scheme could also extend beyond the auditory domain.

Researchers propose that the recovery of language function following stroke depends on the recruitment of perilesional regions in the left hemisphere and/or homologous regions in the right hemisphere. Many investigations of recovery focus on changes in gray matter regions, whereas relatively few examine white matter tracts and none address the role of these tracts in the recovery of verbal working memory. The present study addressed these gaps, examining the role of left versus right hemisphere tracts in the longitudinal recovery of phonological and semantic working memory. For 24 individuals with left hemisphere stroke, we assessed working memory performance within 1 week of stroke (acute time point) and at more than 6 months after stroke (chronic time point). To address whether recovery depends on the recruitment of left or right hemisphere tracts, we assessed whether changes in working memory were related to the integrity of five white matter tracts in the left hemisphere which had been implicated previously in verbal working memory and their right hemisphere analogues. Behavioral results showed significant improvement in semantic but not phonological working memory from the acute to chronic time points. Improvements in semantic working memory significantly correlated with tract integrity as measured by functional anisotropy in the left direct segment of the arcuate fasciculus, inferior fronto-occipital fasciculus and inferior longitudinal fasciculus. The results confirm the role of white matter tracts in language recovery and support the involvement of the left rather than right hemisphere in the recovery of semantic working memory.

Multiple Sclerosis, Cannabinoids, and Cognition

Early adolescent psychological distress and cognition, correlates of resting-state EEG, interregional phase-amplitude coupling.

Cross-frequency coupling between the phase of slower oscillatory activity and the amplitude of faster oscillatory activity in the brain (phase-amplitude coupling; PAC), is a promising new biological marker for mental health. Prior research has demonstrated that PAC is associated with mental health. However, most research has focused on within-region theta-gamma PAC in adults. Our recent preliminary study found increased theta-beta PAC was associated with increased psychological distress in 12 year olds. It is important to investigate how PAC biomarkers relate to mental health and wellbeing in youth. Thus, in this study, we investigated longitudinal associations between interregional (posterior-anterior cortex) resting-state theta-beta PAC (Modulation Index [MI]), psychological distress and wellbeing in N = 99 adolescents (aged 12-15 years). In the right hemisphere, there was a significant relationship, whereby increased psychological distress was associated with decreased theta-beta PAC and psychological distress increased with increased age. In the left hemisphere, there was a significant relationship, whereby decreased wellbeing was associated with decreased theta-beta PAC and wellbeing scores decreased with increased age. This study presents novel findings demonstrating longitudinal relationships between interregional, resting-state theta-beta PAC and mental health and wellbeing in early adolescents. This EEG marker may facilitate improved early identification of emerging psychopathology.

The impact of non-clinical obsessive compulsive symptoms (OCS) on neuropsychological functioning in schizophrenia has received little investigation. We evaluated whether severity and subtype of OCS are associated with executive functioning in schizophrenia. Twenty-nine patients with schizophrenia and 32 healthy subjects completed questionnaire and performance-based measures of executive functioning Overall OCS severity in patients was associated with poorer monitoring and cognitive flexibility per a questionnaire. Obsessing, hoarding, and checking were related to poorer executive functioning in daily life. Performance-based scores showed few correlations with OCS. Findings indicate that severity of non-clinical OCS subtypes contribute to the heterogeneity of executive functions in schizophrenia.

To explore the changes of executive function in patients with temporal lobe epilepsy and analyze its correlation with P300 event-related potentials. Fifty patients with temporal lobe epilepsy and 30 age, gender and education-matched healthy control subjects were assessed by neuropsychological tests, including Montreal cognitive assessment (MoCA), working memory, verbal fluency, trail making, digit span, digit symbol and Stroop color-word interference to detect P300 event-related potentials. In temporal lobe epilepsy group, the scores in MoCA, verbal and non-verbal working memory, verbal fluency, digit span, digit symbol and Stroop test were lower than those of the normal control group. And trail making tests A and B became prolonged (P < 0.05). Comparing with normal control group, temporal lobe epilepsy patients had prolonged latency [(332 ± 33)ms] and decreased P300 amplitude [(10 ± 8)µV] (P < 0.05). Comparing epileptogenic focus group on the left and right sides, there was statistically significant difference in verbal working memory (P < 0.05). There was a negative correlation of P300 latency and MoCA, non-verbal working memory, digit span and digit symbol test scores (r = -0.29--0.45, P < 0.05). And a positive correlation of P300 amplitude and MoCA, non-verbal working memory, digit symbol conversion and Stroop scores was also found (r = 0.37-0.47, P < 0.05). P300 amplitude was more relevant to overall cognitive level and executive functions. Temporal lobe is involved in the regulation of executive functions. Besides a wide range of cognitive impairment, temporal lobe epilepsy patients have a number of executive dysfunctions, including working memory, cognitive flexibility, attention and inhibitory control ability. And an impairment of verbal working memory is evident in left-sided lesion. Their manifestations include decreased latency and amplitude of P300 on executive function tests. Therefore these two objective parameters may be employed to evaluate the cognitive impairment in patients with temporal lobe epilepsy.

Researchers propose that the recovery of language function following stroke depends on the recruitment of perilesional regions in the left hemisphere and/or homologous regions in the right hemisphere (Kiran, 2012). Many investigations of recovery focus on changes in gray matter regions (e.g., Turkeltaub et al., 2011), whereas relatively few examine white matter tracts (e.g., Schlaug et al., 2009) and none address the role of these tracts in the recovery of verbal working memory (WM). The present study addressed these gaps, examining the role of left vs. right hemisphere tracts in the longitudinal recovery of phonological and semantic WM. For 24 individuals with left hemisphere stroke, we assessed WM performance within one week of stroke (acute timepoint) and at more than six months after stroke (chronic timepoint). To address whether recovery depends on the recruitment of left or right hemisphere tracts, we assessed whether changes in WM were related to the integrity of five white matter tracts in the left hemisphere which had been implicated previously in verbal WM and their right hemisphere analogues. Behavioral results showed significant improvement in semantic but not phonological WM from the acute to chronic timepoints. Improvements in semantic WM significantly correlated with tract integrity as measured by functional anisotropy in the left direct segment of the arcuate fasciculus, inferior fronto-occipital fasciculus and inferior longitudinal fasciculus. The results confirm the role of white matter tracts in language recovery and support the involvement of the left rather than right hemisphere in the recovery of semantic WM.

In view of the negative impact of anxiety on working memory, we induced anxiety in 26 patients with acute stroke and 33 healthy controls, and studied how the anxiety affected their emotional reactivity and how the reactivity affected their verbal and visuospatial working memory. We compared the overall findings with those in 1 of our patients (C.B.) who had presented with an abnormally high level of state anxiety. We gave verbal and visuospatial 1-back tasks under both neutral and anxiogenic conditions, and we compared participants' working memory scores, self-reported levels of state anxiety, and electrodermal activity. When comparing performance in the neutral condition, the control and patient groups exhibited disrupted verbal working memory, which was associated with greater electrodermal activity and higher state anxiety during the anxiogenic condition. Although patient C.B. also had heightened electrodermal activity during the anxiogenic condition, she experienced a significant reduction in her state anxiety. Her verbal working memory was better during the anxiogenic than the neutral condition. Because of the phonological (subvocal speech) nature of verbal working memory, a higher level of anxious apprehension could explain the increase in state anxiety and the corresponding disruption of verbal working memory in our patient and control groups during the anxiogenic condition. C.B.'s lower state anxiety and selective improvement in verbal working memory during the anxiogenic condition suggest that she felt less anxious apprehension.

It has been thought that coordination of briefly maintained information (working memory) and social cognition (mentalizing) rely on different brain mechanisms. However, the dorsomedial prefrontal cortex (DMPFC) seems to control the mentalizing and the visual working memory networks. We aimed to show (1) that visual working memory and social cognition share the same neural communication mechanism (i.e., interregional phase-amplitude coupling) and (2) that this mechanism is behaviorally relevant. We analyzed electrical brain activity from 98 volunteers who differed in the extent of (subclinical) autistic personality traits. Participants performed a social, visual and verbal working memory task, each implemented in a low and a high cognitive load version. We analyzed how slow rhythmical brain activity in the DMPFC controls distributed posterior regions associated with working memory and mentalizing via phase-amplitude coupling. First, individuals with low autistic personality traits use slow rhythmical brain activity in the DMPFC to precisely tune communication with posterior brain areas depending on the effort necessary in the visual and social tasks. Second, individuals with high autistic personality traits struggle in fine-tuning this mechanism, which is associated with difficulties in efficiently adapting brain activity to the difficulty level of a visual working memory task; and they demonstrate problems with efficiently synchronizing the relevant cortical network in a social cognition task. While these findings suggest a unified function of brain oscillations in cognitive coordination between social and visual tasks, they could also explain why individuals with high autistic personality traits can have difficulties with demanding cognitive processing and mentalizing.

The Relationship Between Physical Activity and Executive Functions Among Youth in Low-Income Urban Schools in the Northeast and Southwest United States.

ABSTRACTThis study tests the factor structure, measurement invariance, and correlates of the Childhood Executive Functioning Inventory (CHEXI) with a large and diverse sample of 3- to 5-year-olds (n = 844). Consistent with previous studies, a two-factor model that distinguishes working memory from inhibition provides the best fit to the observed data. This two-factor model has been shown to demonstrate strong measurement invariance for different subgroups of children (boys vs. girls, high vs. low income). Whereas boys tend to have greater working memory and inhibition difficulties (Cohen’s d = 0.15 and 0.20, respectively), children from low-income households tend to have more working memory problems than their peers from high-income households (Cohen’s d = 0.25). Finally, correlations between CHEXI scores, examiner reports of child behavior, and child performance on a battery of executive function (EF) tasks were investigated. CHEXI scores were found to be more consistently related to examiner reports of child behavior than child performance on EF tasks. Tthe strengths and weaknesses of the CHEXI as a questionnaire measure of EF are discussed, and directions for future research are suggested.

OBJECTIVES/SPECIFIC AIMS: Attention is a cognitive function that binds perception and behavior. Recent evidence suggests that attention involves phase-amplitude coupling (PAC) of neural signals. PAC occurs when the amplitude of one frequency (frequency for amplitude) is maximal at particular phases of another frequency (frequency for phase). However, some studies suggest PAC improves attention, while others maintain that PAC inhibits attention. The present study seeks to determine whether PAC promotes or inhibits neural signals that underlie attention. METHODS/STUDY POPULATION: Six adult epilepsy patients with implanted electrodes participated in a cued attention task. Subjects participated in a cued attention task where they oriented attention to one side of the screen at a time and discriminated between stimuli as fast as possible with mouse clicks. Perception-related electrodes discriminated the location and/or shape of the target. These were determined with a cluster-based permutation test. Behavior-related electrodes predicted reaction time (RT) with neural activity prior to target appearance. These were determined with correlations between PAC and RT. PAC was calculated using the modulation index (MI). RESULTS/ANTICIPATED RESULTS: We found 47 perception-related electrodes that discriminated location and/or shape of target (p&lt;0.05, FDR corrected). We found 27 behavior-related electrodes where PAC prior to the target predicted RT (p&lt;0.05 FDR corrected). There was little overlap between the perception-related and behavior-related electrodes (3%). PAC also did not discriminate left-sided and right-sided cues. In addition, behavior-related electrodes had less local neural activity and higher PAC during the period of cued attention than perception-related electrodes. DISCUSSION/SIGNIFICANCE OF IMPACT: PAC minimally facilitates perceptual aspect of visual attention. However, PAC facilitate response speed. We suggest that PAC might improve response speed by “quieting” task irrelevant neural activity. For the same reason, PAC is absent in electrodes that are actively processing meaningful streams of visual data. These findings highlight separable aspects of the human attention system and how PAC contributes to both. Future directions include determining differences in PAC for attentional disorders like ADHD and neurological neglect.