Activation In Fusiform Gyrus Research Articles

Reduced Fusiform Gyrus Activation During Face Processing in Pediatric Brain Tumor Survivors.

The neural mechanisms contributing to the social problems of pediatric brain tumor survivors (PBTS) are unknown. Face processing is important to social communication, social behavior, and peer acceptance. Research with other populations with social difficulties, namely autism spectrum disorder, suggests atypical brain activation in areas important for face processing. This case-controlled functional magnetic resonance imaging (fMRI) study compared brain activation during face processing in PBTS and typically developing (TD) youth. Participants included 36 age-, gender-, and IQ-matched youth (N = 18 per group). PBTS were at least 5 years from diagnosis and 2 years from the completion of tumor therapy. fMRI data were acquired during a face identity task and a control condition. Groups were compared on activation magnitude within the fusiform gyrus for the faces condition compared to the control condition. Correlational analyses evaluated associations between neuroimaging metrics and indices of social behavior for PBTS participants. Both groups demonstrated face-specific activation within the social brain for the faces condition compared to the control condition. PBTS showed significantly decreased activation for faces in the medial portions of the fusiform gyrus bilaterally compared to TD youth, ps ≤ .004. Higher peak activity in the left fusiform gyrus was associated with better socialization (r = .53, p < .05). This study offers initial evidence of atypical activation in a key face processing area in PBTS. Such atypical activation may underlie some of the social difficulties of PBTS. Social cognitive neuroscience methodologies may elucidate the neurobiological bases for PBTS social behavior.

Odors Associated With Autobiographical Memory Induce Visual Imagination of Emotional Scenes as Well as Orbitofrontal-Fusiform Activation.

Specific odors can induce memories of the past, especially those associated with autobiographical and episodic memory. Odors associated with autobiographical memories have been found to elicit stronger activation in the orbitofrontal cortex, hippocampus, and parahippocampus compared with odors not linked to personal memories. Here, we examined whether continuous odor stimuli associated with autobiographical memories could activate the above olfactory areas in older adults and speculated regarding whether this odor stimulation could have a protective effect against age-related cognitive decline. Specifically, we used functional magnetic resonance imaging to investigate the relationship between blood oxygen levels in olfactory regions and odor-induced subjective memory retrieval and emotions associated with autobiographical memory in older adults. In our group of healthy older adults, the tested odors induced autobiographical memories that were accompanied by increasing levels of retrieval and the feeling of being “brought back in time.” The strength of the subjective feelings, including vividness of the memory and degree of comfort, impacted activation of the left fusiform gyrus and left posterior orbitofrontal cortex. Further, our path model suggested that the strength of memory retrieval and of the emotions induced by odor-evoked autobiographical memories directly influenced neural changes in the left fusiform gyrus, and impacted left posterior orbitofrontal cortex activation through the left fusiform response.

Dissociating the Neural Correlates of Consciousness and Task Relevance in Face Perception Using Simultaneous EEG-fMRI.

Current theories of visual consciousness disagree about whether it emerges during early stages of processing in sensory brain regions or later when a widespread frontoparietal network becomes involved. Moreover, disentangling conscious perception from task-related postperceptual processes (e.g., report) and integrating results across different neuroscientific methods remain ongoing challenges. The present study addressed these problems using simultaneous EEG-fMRI and a specific inattentional blindness paradigm with three physically identical phases in female and male human participants. In phase 1, participants performed a distractor task during which line drawings of faces and control stimuli were presented centrally. While some participants spontaneously noticed the faces in phase 1, others remained inattentionally blind. In phase 2, all participants were made aware of the task-irrelevant faces but continued the distractor task. In phase 3, the faces became task-relevant. Bayesian analysis of brain responses demonstrated that conscious face perception was most strongly associated with activation in fusiform gyrus (fMRI) as well as the N170 and visual awareness negativity (EEG). Smaller awareness effects were revealed in the occipital and prefrontal cortex (fMRI). Task-relevant face processing, on the other hand, led to strong, extensive activation of occipitotemporal, frontoparietal, and attentional networks (fMRI). In EEG, it enhanced early negativities and elicited a pronounced P3b component. Overall, we provide evidence that conscious visual perception is linked with early processing in stimulus-specific sensory brain areas but may additionally involve prefrontal cortex. In contrast, the strong activation of widespread brain networks and the P3b are more likely associated with task-related processes.SIGNIFICANCE STATEMENT How does our brain generate visual consciousness-the subjective experience of what it is like to see, for example, a face? To date, it is hotly debated whether it emerges early in sensory brain regions or later when a widespread frontoparietal network is activated. Here, we use simultaneous fMRI and EEG for high spatial and temporal resolution and demonstrate that conscious face perception is predominantly linked to early and occipitotemporal processes, but also prefrontal activity. Task-related processes (e.g., decision-making), on the other hand, elicit brain-wide activations including late and strong frontoparietal activity. These findings challenge numerous previous studies and highlight the importance of investigating the neural correlates of consciousness in the absence of task relevance.

Visuomotor Adaptation Brain Changes During a Spaceflight Analog With Elevated Carbon Dioxide (CO2): A Pilot Study.

Astronauts on board the International Space Station (ISS) must adapt to several environmental challenges including microgravity, elevated carbon dioxide (CO2), and isolation while performing highly controlled movements with complex equipment. Head down tilt bed rest (HDBR) is an analog used to study spaceflight factors including body unloading and headward fluid shifts. We recently reported how HDBR with elevated CO2 (HDBR+CO2) affects visuomotor adaptation. Here we expand upon this work and examine the effects of HDBR+CO2 on brain activity during visuomotor adaptation. Eleven participants (34 ± 8 years) completed six functional MRI (fMRI) sessions pre-, during, and post-HDBR+CO2. During fMRI, participants completed a visuomotor adaptation task, divided into baseline, early, late and de-adaptation. Additionally, we compare brain activity between this NASA campaign (30-day HDBR+CO2) and a different campaign with a separate set of participants (60-day HDBR with normal atmospheric CO2 levels, n = 8; 34.25 ± 7.9 years) to characterize the specific effects of CO2. Participants were included by convenience. During early adaptation across the HDBR+CO2 intervention, participants showed decreasing activation in temporal and subcortical brain regions, followed by post- HDBR+CO2 recovery. During late adaptation, participants showed increasing activation in the right fusiform gyrus and right caudate nucleus during HDBR+CO2; this activation normalized to baseline levels after bed rest. There were no correlations between brain changes and adaptation performance changes from pre- to post HDBR+CO2. Also, there were no statistically significant differences between the HDBR+CO2 group and the HDBR controls, suggesting that changes in brain activity were due primarily to bed rest rather than elevated CO2. Five HDBR+CO2 participants presented with optic disc edema, a sign of Spaceflight Associated Neuro-ocular Syndrome (SANS). An exploratory analysis of HDBR+CO2 participants with and without signs of SANS revealed no group differences in brain activity during any phase of the adaptation task. Overall, these findings have implications for spaceflight missions and training, as ISS missions require individuals to adapt to altered sensory inputs over long periods in space. Further, this is the first study to verify the HDBR and elevated CO2 effects on the neural correlates of visuomotor adaptation.

Disruption of Neural Activity and Functional Connectivity in Adolescents With Major Depressive Disorder Who Engage in Non-suicidal Self-Injury: A Resting-State fMRI Study.

Background: Non-suicidal self-injury (NSSI), which commonly occurs during adolescence, often co-occurs with major depressive disorder (MDD). However, the underlying neurobiological mechanisms in adolescents with MDD who engage in NSSI remain unclear. The current study examined the aberrant local neural activity in certain areas of the visual regions and the default mode network (DMN) and the resting-state functional connectivity (rs-FC) in changed brain regions in adolescents with MDD who engage in NSSI and adolescents with MDD only.Methods: A total of 67 adolescents with MDD were divided into two groups based on their NSSI behavior: the NSSI group (n = 31) and an age-, gender-, and education-matched MDD group (n = 36). The Hamilton Depression Rating Scale (HAMD) was used to assess the severity of MDD. Amplitude of low-frequency fluctuation (ALFF) analysis was used to detect alterations in local neural activity. Brain regions with aberrant neural activity were considered regions of interest (ROI). ALFF-based rs-FC analysis was used to further explore the underlying changes in connectivity between ROI and other areas in the NSSI group. Correlation analyses were performed to examine the relationship between neural changes and clinical characteristics.Results: There was no significant difference in HAMD scores between the two groups. ALFF analysis revealed that, compared to adolescents with MDD only, adolescents with MDD who engaged in NSSI displayed significantly enhanced neural activity in the right fusiform gyrus (FFG. R) and the right median cingulate and paracingulate gyri (DCG. R). Significantly reduced rs-FC of the FFG. R-bilateral medial orbital of the superior frontal gyrus (ORBsupmed. L/R)/bilateral medial superior frontal gyrus (SFGmed. L/R), FFG. R-bilateral posterior cingulate gyrus (PCG. L/R), DCG. R-left pallidum (PAL. L), DCG. R-right superior temporal gyrus (STG. R), and DCG. R-right postcentral gyrus (PoCG. R)/right inferior parietal lobule (IPL. R) was found in adolescents with MDD who were engaged in NSSI. Additionally, no significant correlations were observed between ALFF or rs-FC values and the HAMD scores between the two groups.Limitations: Owing to the cross-sectional design, the alterations in ALFF and rs-FC values in the FFG. R and DCG. R could not demonstrate that it was a state or feature in adolescents with MDD who engaged in NSSI. Additionally, the sample size was relatively small.Conclusions: This study highlights changes in regional brain activity and remote connectivity in the FFG. R and DCG. R in adolescents with MDD who engage in NSSI. This could provide a new perspective for further studies on the neurobiological mechanism of NSSI behavior in adolescents with MDD.

Maturation of hemispheric specialization for face encoding during infancy and toddlerhood

Little is known about the neural processes associated with attending to social stimuli during infancy and toddlerhood. Using infant magnetoencephalography (MEG), fusiform gyrus (FFG) activity while processing Face and Non-Face stimuli was examined in 46 typically developing infants 3 to 24 months old (28 males). Several findings indicated FFG maturation throughout the first two years of life. First, right FFG responses to Face stimuli decreased as a function of age. Second, hemispheric specialization to the face stimuli developed somewhat slowly, with earlier right than left FFG peak activity most evident after 1 year of age. Right FFG activity to Face stimuli was of clinical interest, with an earlier right FFG response associated with better performance on tests assessing social and cognitive ability. Building on the above, clinical studies examining maturational change in FFG activity (e.g., lateralization and speed) in infants at-risk for childhood disorders associated with social deficits are of interest to identify atypical FFG maturation before a formal diagnosis is possible.

Shared and unique neural circuitry underlying temporally unpredictable threat and reward processing

Temporally unpredictable stimuli influence behavior across species, as previously demonstrated for sequences of simple threats and rewards with fixed or variable onset. Neuroimaging studies have identified a specific frontolimbic circuit that may become engaged during the anticipation of temporally unpredictable threat (U-threat). However, the neural mechanisms underlying processing of temporally unpredictable reward (U-reward) are incompletely understood. It is also unclear whether these processes are mediated by overlapping or distinct neural systems. These knowledge gaps are noteworthy given that disruptions within these neural systems may lead to maladaptive response to uncertainty. Here, using functional magnetic resonance imaging data from a sample of 159 young adults, we showed that anticipation of both U-threat and U-reward elicited activation in the right anterior insula, right ventral anterior nucleus of the thalamus and right inferior frontal gyrus. U-threat also activated the right posterior insula and dorsal anterior cingulate cortex, relative to U-reward. In contrast, U-reward elicited activation in the right fusiform and left middle occipital gyrus, relative to U-threat. Although there is some overlap in the neural circuitry underlying anticipation of U-threat and U-reward, these processes appear to be largely mediated by distinct circuits. Future studies are needed to corroborate and extend these preliminary findings.

A combined fMRI and EMG study of emotional contagion following partial sleep deprivation in young and older humans

Sleep deprivation is proposed to inhibit top-down-control in emotion processing, but it is unclear whether sleep deprivation affects emotional mimicry and contagion. Here, we aimed to investigate effects of partial sleep deprivation on emotional contagion and mimicry in young and older humans. Participants underwent partial sleep deprivation (3 h sleep opportunity at the end of night), crossed-over with a full sleep condition in a balanced order, followed by a functional magnetic resonance imaging and electromyography (EMG) experiment with viewing of emotional and neutral faces and ratings of emotional responses. The final sample for main analyses was n = 69 (n = 36 aged 20–30 years, n = 33 aged 65–75 years). Partial sleep deprivation caused decreased activation in fusiform gyri for angry faces and decreased ratings of happiness for all stimuli, but no significant effect on the amygdala. Older participants reported more anger compared to younger participants, but no age differences were seen in brain responses to emotional faces or sensitivity to partial sleep deprivation. No effect of the sleep manipulation was seen on EMG. In conclusion, emotional contagion, but not mimicry, was affected by sleep deprivation. Our results are consistent with the previously reported increased negativity bias after insufficient sleep.The Stockholm sleepy brain study: effects of sleep deprivation on cognitive and emotional processing in young and old. https://clinicaltrials.gov/ct2/show/NCT02000076.

Effect of a High-Intensity Tandem Bicycle Exercise Program on Clinical Severity, Functional Magnetic Resonance Imaging, and Plasma Biomarkers in Parkinson's Disease.

Rationale: The optimal modality, intensity, duration, frequency, and dose–response of exercise as a therapy for Parkinson's Disease (PD) are insufficiently understood.Objective: To assess the impact of a high-intensity tandem bicycle program on clinical severity, biomarkers, and functional MRI (fMRI) in PD.Methods: A single-center, parallel-group clinical trial was conducted. Thirteen PD patients aged 65 or younger were divided in two groups: a control group and an intervention group that incorporated a cycling program at 80% of each individual's maximum heart rate (HR) (≥80 rpm), three times a week, for 16 weeks. Both groups continued their conventional medications for PD. At baseline and at the end of follow-up, we determined in all participants the Unified Parkinson's Disease Rating Scale, anthropometry, VO2max, PD biomarkers, and fMRI.Results: VO2max improved in the intervention group (IG) (+5.7 ml/kg/min), while it slightly deteriorated in the control group (CG) (−1.6 ml/kg/min) (p = 0.041). Mean Unified Parkinson's Disease Rating Scale (UPDRS) went down by 5.7 points in the IG and showed a small 0.9-point increase in the CG (p = 0.11). fMRI showed activation of the right fusiform gyrus during the motor task and functional connectivity between the cingulum and areas of the frontal cortex, and between the cerebellar vermis and the thalamus and posterior temporal gyrus. Plasma brain-derived neurotrophic factor (BDNF) levels increased more than 10-fold in the IG and decreased in the CG (p = 0.028). Larger increases in plasma BDNF correlated with greater decreases in UPDRS (r = −0.58, p = 0.04).Conclusions: Our findings suggest that high-intensity tandem bicycle improves motor function and biochemical and functional neuroimaging variables in PD patients.Trial registration number: ISRCTN 13047118, Registered on February 8, 2018.

Neural correlates of top-down guidance of attention to food: An fMRI study

We investigated the neural correlates of working memory guided attentional selection of food versus non-food stimuli in young women. Participants were thirty-two women, aged 20.6y (± 0.5) who were presented with a cue (food or non-food item) to hold in working memory. Subsequently, they had to search for a target in a 2-item display where target and distractor stimuli were each flanked by a picture of a food or a non-food item. The behavioural data showed that attention is particularly efficiently drawn to food stimuli when thinking about food. Using fMRI, we found that holding a non-food versus food stimulus in working memory was associated with increased activity in occipital gyrus, fusiform, inferior and superior frontal gyrus. In the posterior cingulum, retrosplenial cortex, a food item that re-appeared in the search array when it was held in memory led to a reduced response, compared to when it did not re-appear. The reverse effect was found for non-food stimuli. The extent of the reappearance effect correlated with the attentional capture of food as measured behaviourally. In conclusion, these results suggest that holding food in mind may bias attention because thinking of food facilitated neuronal responses to sensory input related to food stimuli and because holding food-related information in mind is less taxing on memory.

Adolescent gender differences in neural reactivity to a friend’s positive affect and real-world positive experiences in social contexts

Peers become increasingly important during adolescence, with emerging gender differences in peer relationships associated with distinct behavioral and emotional outcomes. Males tend to socialize in larger peer groups with competitive interactions, whereas females engage in longer bouts of dyadic interaction with more intimacy. To examine gender differences in neural response to ecologically valid displays of positive affect and future social interactions, 52 adolescents (14–18 years old; female = 30) completed a social reward functional magnetic resonance imaging (fMRI) task with videos of a same-gender best friend (BF) or unfamiliar peer (UP) expressing positive (versus neutral) affect. Participants completed ecological momentary assessment of social experiences for two 5-day intervals. Compared with females, males more often reported that their happiest experience in the past hour occurred with class/teammates. Females and males displayed greater fusiform gyrus (FG) activation during BF and UP conditions, respectively (pvoxel<0.0001, pcluster<0.05, family-wise error). Compared with males, females exhibited greater nucleus accumbens (NAcc)-precuneus functional connectivity to BF Positive> UP Positive. An exploratory analysis indicated that the association of male gender with a greater proportion of positive experiences with class/teammates was statistically mediated by greater NAcc-precuneus functional connectivity. Gender differences in positive social experiences may be associated with reward and social cognition networks.

Positive intergroup contact modulates fusiform gyrus activity to black and white faces

In this study, we investigated the effect of intergroup contact on processing of own- and other-race faces using functional Magnetic Resonance Imaging (fMRI). Previous studies have shown a neural own-race effect with greater BOLD response to own race compared to other race faces. In our study, white participants completed a social-categorization task and an individuation task while viewing the faces of both black and white strangers after having answered questions about their previous experiences with black people. We found that positive contact modulated BOLD activity in the right fusiform gyrus (rFG) and left inferior occipital gyrus (lIOC), regions associated with face processing. Within these regions, higher positive contact was associated with higher activity when processing black, compared to white faces during the social categorisation task. We also found that in both regions a greater amount of individuating experience with black people was associated with greater activation for black vs. white faces in the individuation task. Quantity of contact, implicit racial bias and negatively valenced contact showed no effects. Our findings suggest that positive contact and individuating experience directly modulate processing of out-group faces in the visual cortex, and illustrate that contact quality rather than mere familiarity is an important factor in reducing the own race face effect.

Reproducibility of amygdala activation in facial emotion processing at 7T

Despite its importance as the prime method for non-invasive assessment of human brain function, functional MRI (fMRI) was repeatedly challenged with regards to the validity of the fMRI-derived brain activation maps. Amygdala fMRI was particularly targeted, as the amygdala’s anatomical position in the ventral brain combined with strong magnetic field inhomogeneities and proximity to large vessels pose considerable obstacles for robust activation mapping.In this high-resolution study performed at ultra-high field (7T) fMRI, we aimed at (1) investigating systematic replicability of amygdala group-level activation in response to an established emotion processing task by varying task instruction and acquisition parameters and (2) testing for intra- and intersession reliability.At group-level, our results show statistically significant activation in bilateral amygdala and fusiform gyrus for each of the runs acquired. In addition, while fusiform gyrus activations are consistent across runs and sessions, amygdala activation levels show habituation effects across runs. This amygdala habituation effect is replicated in a session repeated two weeks later. Varying task instruction between matching emotions and matching persons does not change amygdala activation strength. Also, comparing two acquisition protocols with repetition times of either 700 ​ms or 1400 ​ms did not result in statistically significant differences of activation levels.Regarding within-subject reliability of amygdala activation, despite considerable variance in individual habituation patterns, we report fair to good inter-session reliability for the first run and excellent reliability for averages over runs.We conclude that high-resolution fMRI at 7T allows for robust mapping of amygdala activation in a broad range of variations. Our results of amygdala 7T fMRI are suitable to inform methodology and may encourage future studies to continue using emotion discrimination paradigms in clinical and non-clinical applications.

Pathologic tearfulness after limbic encephalitis: A novel disorder and its neural basis.

ObjectiveWe investigated the nature and neural foundations of pathologic tearfulness in a uniquely large cohort of patients who had presented with autoimmune limbic encephalitis (aLE).MethodsWe recruited 38 patients (26 men, 12 women; median age 63.06 years; interquartile range [IQR] 16.06 years) in the postacute phase of aLE who completed questionnaires probing emotion regulation. All patients underwent structural/functional MRI postacutely, along with 67 age- and sex-matched healthy controls (40 men, 27 women; median age 64.70 years; IQR 19.87 years). We investigated correlations of questionnaire scores with demographic, clinical, neuropsychological, and brain imaging data across patients. We also compared patients diagnosed with pathologic tearfulness and those without, along with healthy controls, on gray matter volume, resting-state functional connectivity, and activity.ResultsPathologic tearfulness was reported by 50% of the patients, while no patient reported pathologic laughing. It was not associated with depression, impulsiveness, memory impairment, executive dysfunction in the postacute phase, or amygdalar abnormalities in the acute phase. It correlated with changes in specific emotional brain networks: volume reduction in the right anterior hippocampus, left fusiform gyrus, and cerebellum, abnormal hippocampal resting-state functional connectivity with the posteromedial cortex and right middle frontal gyrus, and abnormal hemodynamic activity in the left fusiform gyrus, right inferior parietal lobule, and ventral pons.ConclusionsPathologic tearfulness is common following aLE, is not a manifestation of other neuropsychiatric features, and reflects abnormalities in networks of emotion regulation beyond the acute hippocampal focus. The condition, which may also be present in other neurologic disorders, provides novel insights into the neural basis of affective control and its dysfunction in disease.

Processing of Positive Visual Stimuli Before and After Symptoms Provocation in Posttraumatic Stress Disorder – A Functional Magnetic Resonance Imaging Study of Trauma-Affected Male Refugees

Background Symptoms of anhedonia are often central to posttraumatic stress disorder (PTSD), but it is unclear how anhedonia is affected by processes induced by reliving past traumatic memories. Methods Sixty-nine male refugees (PTSD = 38) were interviewed and scanned with functional magnetic resonance imaging while viewing positive, neutral and Scrambled Pictures after being read personalized scripts evoking an emotionally neutral memory and a traumatic memory. We further measured postprovocation state symptoms, physiological measures and PTSD symptoms. We tested whether neural activity associated with positive picture viewing in participants with PTSD was differentially affected by symptom provocation compared to controls. Results For the pictures > scrambled contrast (Positive contrast), PTSD participants had significantly less activity than controls in fusiform gyrus, right inferior temporal gyrus and left middle occipital gyrus. The Positive contrast activity in fusiform gyrus scaled negatively with anhedonia symptoms in PTSD participants after controlling for total PTSD severity. Relative to the emotionally Neutral Script, the Trauma Script decreased positive picture viewing activity in posterior cingulate cortex, precuneus and left calcarine gyrus, but there was no difference between PTSD participants and controls. Conclusions We found reduced responsiveness of higher visual processing of emotionally positive pictures in PTSD. The significant correlation found between positive picture viewing activity and anhedonia suggests the reduced responsiveness to be due to the severity of anhedonia.

Naming fMRI predicts the effect of temporal lobe resection on language decline.

ObjectiveTo develop language functional MRI (fMRI) methods that accurately predict postsurgical naming decline in temporal lobe epilepsy (TLE).MethodsForty‐six patients with TLE (25 left) and 19 controls underwent two overt fMRI paradigms (auditory naming and picture naming, both with active baseline conditions) and one covert task (verbal fluency). Clinical naming performance was assessed preoperatively and 4 months following anterior temporal lobe resection. Preoperative fMRI activations were correlated with postoperative naming decline. Individual laterality indices (LI) were calculated for temporal (auditory and picture naming) and frontal regions (verbal fluency) and were considered as predictors of naming decline in multiple regression models, along with other clinical variables (age at onset of seizures, preoperative naming scores, hippocampal volume, age).ResultsIn left TLE patients, activation of the left posterior inferior temporal gyrus during auditory naming and activation of left fusiform gyrus during picture naming were related to greater postoperative naming decline. Activation LI were the best individual predictors of naming decline in a multivariate regression model. For picture naming, an LI of higher than 0.34 gave 100% sensitivity and 92% specificity (positive predictive value (PPV) 91.6%). For auditory naming, a temporal lobe LI higher than 0.18 identified all patients with a clinically significant naming decline with 100% sensitivity and 58% specificity (PPV: 58.3%). No effect was seen for verbal fluency.InterpretationAuditory and picture naming fMRI are clinically applicable to predict postoperative naming decline after left temporal lobe resection in individual patients, with picture naming being more specific.

Functional Magnetic Resonance Imaging Detects Between-Group Differences in Neural Activation Among Men with Delayed Orgasm Compared with Normal Controls: Preliminary Report

BackgroundMechanisms underlying delayed orgasm (DO) are poorly understood; however, known effects of psychotropic medications on sexual function provides a rationale for aberrant central nervous system signaling as a cause. AimTo compare brain activation between men with normal orgasm and those with lifelong DO during sexual stimulation using brain fMRI algorithms. Methods3 subjects with self-reported life-long DO and 6 normal controls were included in this study. The International Index of Erectile Function, Male Sexual Health Questionnaire, and self-reported time to orgasm were used to assess sexual function. Subjects underwent a 3-T fMRI study while viewing 3 video clips: a neutral control (NC), a positive emotional control (EC), and a sexual condition (SC). Each video sequence was repeated 5 times, with 50-second clips presented in a randomized fashion. fMRI data were analyzed in a block design manner to determine areas of differential brain activation between groups. The Allen Brain Atlas of gene expression in the human brain was used to identify signaling pathways in the areas of differential fMRI activation between the DO and control groups. OutcomesThe primary outcome was differential activation of fMRI neural activation between groups. ResultsAnalysis of differential activation in the SC compared with the NC and EC revealed increased activation in the right frontal operculum (P = .003), right prefrontal gyrus (P = .003), and inferior occipital gyrus (P = .003). Increased activation in the right fusiform gyrus of the occipital lobe and the right hippocampus (P = .0004) was seen in the DO group compared with controls. Using the Allen Atlas of Human Brain Expression, we identified corresponding neurotransmitter receptors to this region, including adenosine receptors, muscarinic and nicotinic cholinergic receptors, cannabinoid receptors, and dopamine receptors, among others. Clinical ImplicationsLifelong DO in men may be due to abnormal neurotransmitter signaling leading to poor progression of arousal due to aberrant processing of sexual cues. Identification of neurotransmitter pathways by fMRI will aid the development of pharmacotherapeutic agents. Strengths & LimitationsStrengths of this study include the novel application of functional neuroimaging to investigate the pathogenesis of DO. Limitations include the small sample size, making this study exploratory in nature. ConclusionThis study revealed differences in brain activation on visualization of sexual stimuli in men with a history of DO compared with controls. Identified regions are rich in numerous neurotransmitter receptor subtypes and may be amenable to pharmacologic targeting to identify novel therapies for these men.Flannigan R, Heier L, Voss H, et al. Functional Magnetic Resonance Imaging Detects Between-Group Differences in Neural Activation Among Men with Delayed Orgasm Compared with Normal Controls: Preliminary Report. J Sex Med 2019:16;1246–1254.

The Effect of Exercise on Neural Activation in Older Adults

Acute exercise (EX) affects neural activation, assessed with functional magnetic resonance imaging (fMRI), and is a suggested mechanism in the effects of EX on behavioral measures of cognition. PURPOSE: We investigated the effect of EX on neural activation during a set switching task (SST). METHODS: Six healthy, right-handed older adults (M=71.4±5.1) completed two separate visits [EX; 30-min of cycling at 55-65%Heart Rate Reserve and rest (RS); 30-min of seated rest]. After EX or RS participants completed a SST during an fMRI. SSTs are a measure of executive function where participants shift attention between sets of rules during the task. Switch cost (cost) is the performance difference between switching (i.e. A, B, A) and repeat trials (i.e. A, A, A). The conditions included rest, a high switching block [70% switching, 30% repeat trials (HS)], and a low switching block [20% switching, 80% repeat trials (LS)]. fMRI analyses using FSL included assessment of main effects of activation during HS and LS blocks during EX and RS and a comparison of activation with reaction time cost. RESULTS: Across both HS and LS and EX and RS, participants similarly activated the lateral occipital cortex and frontopolar area. In addition, there was significant activation of the superior and inferior frontal gyri, middle frontal gyrus, cerebellum VIIb, thalamus, caudate, and insula following RS in HS and LS. There were no unique areas of activation in HS following EX, however in LS there was activation in the temporal occipital fusiform gyrus, inferior frontal gyrus, and middle frontal gyrus. In relation to performance, cost during HS was associated with activation of the cerebellum VIIb following EX and activation of the thalamus and occipital pole following RS. Further, cost during LS was associated with activation in the frontopolar area after EX and activation in the thalamus following RS. CONCLUSION: Similar activation during HS and LS following rest and EX suggests a common network for SSTs. During the HS blocks, EX did not elicit additional unique activation, as seen following RS or the LS block, suggesting EX-induced efficiency. More research is needed to better understand the implication of differential activation. Results presented at ACSM will include additional participants; findings and conclusions will reflect the final analyses.

Posterior parietal influences on visual network specialization during development: An fMRI study of functional connectivity in children ages 9 to 12

Visual processing in the primate brain is highly organized along the ventral visual pathway, although it is still unclear how categorical selectivity emerges in this system. While many theories have attempted to explain the pattern of visual specialization within the ventral occipital and temporal areas, the biased connectivity hypothesis provides a framework which postulates extrinsic connectivity as a potential mechanism in shaping the development of category selectivity. As the posterior parietal cortex plays a central role in visual attention, we examined whether the pattern of parietal connectivity with the face and scene processing regions is closely linked with the functional properties of these two visually selective networks in a cohort of 60 children ages 9 to 12. Functionally localized face and scene selective regions were used in deriving each visual network's resting-state functional connectivity. The children's face and scene processing networks appeared to show a weak network segregation during resting state, which was confirmed when compared to that of a group of gender and handedness matched adults. Parietal regions of these children showed differential connectivity with the face and scene networks, and the extent of this differential parietal-visual connectivity predicted individual differences in the degree of segregation between the two visual networks, which in turn predicted individual differences in visual perception performance. Finally, the pattern of parietal connectivity with the face processing network also predicted the foci of face-related activation in the right fusiform gyrus across children. These findings provide evidence that extrinsic connectivity with regions such as the posterior parietal cortex may have important implications in the development of specialized visual processing networks.

Hemodynamic and electrocortical reactivity to specific scene contents in emotional perception.

Emotional scene perception is characterized by enhanced neural activity across broad regions of visual cortex, the frontoparietal network, and anterior corticolimbic structures. In human fMRI and electrocortical experiments, activation enhancement is strongly related to self-reported emotional arousal evoked by scene stimuli. However, an additional bias in reaction to pleasant scenes has been reported in a subset of emotion-enhanced brain regions. Human fMRI and primate electrophysiological studies show biased frontoparietal network activity in response to rewarding cues. In addition, activation in lateral occipital regions may show a bias in pleasant scene perception, as shown in fMRI and in the early posterior negativity (EPN) ERP component. To define this potential pleasure bias, we presented a balanced set of naturalistic scenes to participants during separate fMRI and ERP recording sessions. Consistent with past work, the amplitude of the slow-wave late positive potential (LPP), as well as hemodynamic activity in fusiform gyrus and amygdala, showed equivalent enhancement across highly arousing pleasant and unpleasant, relative to neutral scenes. In addition to this emotional enhancement, the EPN component, as well as hemodynamic activity in lateral occipital cortex and frontoparietal network, showed greater reactivity during highly arousing pleasant relative to unpleasant scenes, consistent with a pleasure bias. The interpretation of this pattern of reactivity is discussed with respect to selective and evolved attention mechanisms.