OBJECTIVE: To examine whether functional connectivity (FC) of the occipital gyrus differs between patients with Parkinson\'s disease (PD) motor subtypes and healthy controls (HCs).
METHODS: We enrolled 30 PD patients exhibiting tremor dominance (TD), 43 PD patients with postural instability and gait disturbance (PIGD), and 42 HCs. The occipital gyrus was partitioned into six areas of interest, as seed points, via the Anatomical Automatic Labeling template to compare the FC of the three groups and analyze the relationship of FC with clinical scales.
RESULTS: Compared with the PIGD group, the TD group showed increased FC between the left superior occipital gyrus (SOG.L) and right median cingulate and paracingulate gyri (DCG.R)/right paracentral lobule/bilateral inferior parietal, but supramarginal and angular gyri; the left middle occipital gyrus (MOG.L) and left posterior cingulate gyrus (PCG.L); the MOG.R and SOG.L/right calcarine fissure and surrounding cortex/DCG.R/PCG.L/right cuneus; the left inferior occipital gyrus (IOG.L) and right caudate nucleus; and the IOG.R and PCG.L.
CONCLUSIONS: Differentiated FC between the occipital gyrus and other brain areas within the PD motor subtypes, which may serve as neural markers to distinguish between patients with TD and PIGD PD.

BACKGROUND: The neurobiological underpinnings of Autism Spectrum Disorder (ASD) are diverse and likely multifactorial. One possible mechanism is increased oxidative stress leading to altered neurodevelopment and brain function. However, this hypothesis has mostly been tested in post-mortem studies. So far, available in vivo studies in autistic individuals have reported no differences in glutathione (GSH) levels in frontal, occipital, and subcortical regions. However, these studies were limited by the technically challenging quantification of GSH, the main brain antioxidant molecule. This study aimed to overcome previous studies\' limitations by using a GSH-tailored spectroscopy sequence and optimised quantification methodology to provide clarity on GSH levels in autistic adults.
METHODS: We used spectral editing proton-magnetic resonance spectroscopy (1H-MRS) combined with linear combination model fitting to quantify GSH in the dorsomedial prefrontal cortex (DMPFC) and medial occipital cortex (mOCC) of autistic and non-autistic adults (male and female). We compared GSH levels between groups. We also examined correlations between GSH and current autism symptoms, measured using the Autism Quotient (AQ).
RESULTS: Data were available from 31 adult autistic participants (24 males, 7 females) and 40 non-autistic participants (21 males, 16 females); the largest sample to date. The GSH levels did not differ between groups in either region. No correlations with AQ were observed.
CONCLUSIONS: GSH levels as measured using 1H-MRS are unaltered in the DMPFC and mOCC regions of autistic adults, suggesting that oxidative stress in these cortical regions is not a marked neurobiological signature of ASD.

The activity of occipitotemporal regions involved in linguistic reading processes, such as the ventral occipitotemporal cortex (vOT), is believed to exhibit strong interactions during higher-order language processing, specifically in the connectivity between the occipital gyrus and the temporal gyrus. In this study, we utilized functional magnetic resonance imaging (fMRI) with psychophysiological interaction (PPI) and dynamic causal modeling (DCM) to investigate the functional and effective connectivity in the occipitotemporal network during speed reading. We conducted the experiment with native Japanese speakers who underwent and without speed-reading training and subsequently performed established reading tasks at different speeds (slow, medium, and fast) while undergoing 3-Tesla Siemens fMRI. Our activation analyses revealed significant changes in occipital and temporal regions as reading speed increased, indicating functional connectivity within the occipitotemporal network. DCM results further demonstrated more intricate effective connections and high involvement within the occipitotemporal pathway: (1) reading signals originated from the inferior occipital gyrus (iO), distributed to the vOT and the posterior superior temporal sulcus (pSTS), and then gathered in the anterior superior temporal sulcus (aSTS); (2) reading speed loads had modulation effects on the pathways from the aSTS to vOT and from the iO to vOT. These findings highlight the complex connectivity and dynamic interactions within the occipitotemporal network during speed-reading processes.

Abuse of methamphetamine has aroused concern worldwide. Stimulant use and sexual behaviours have been linked in behavioural and epidemiological studies. Although methamphetamine-related neurofunctional differences are reported in previous studies, only few studies have examined neurofunctional changes related to methamphetamine and sexual cues in methamphetamine dependence from short- to long-term abstinence.
Neurofunctional changes were measured using a cue-reactivity task involving methamphetamine, sexual, and neutral cues in 20 methamphetamine abusers who were evaluated after a short- (1 week to 3 months) and long-term (10-15 months) abstinence.
Five brain regions mainly involved in the occipital lobe and the parietal lobe were found with the group-by-condition interaction. Region-of-interest analyses found higher sexual-cue-related activation than other two activations in all five brain regions in the long-term methamphetamine abstinence group while no group differences were found. Negative relationships between motor impulsivity and methamphetamine- or sexual-cue-related activations in the left middle occipital gyrus, the superior parietal gyrus and the right angular gyrus were found.
The findings suggested that methamphetamine abstinence may change the neural response of methamphetamine abusers to methamphetamine and sexual cues, and the neurofunction of the five brain regions reported in this study may partly recover with long-term methamphetamine abstinence. Given the use and relapse of methamphetamine for sexual purposes, the findings of this study may have particular clinical relevance.

BACKGROUND: Childhood maltreatment (CM) is a well-established risk factor for major depressive disorder (MDD). The neural mechanisms linking childhood maltreatment experiences to changes in brain functional networks and the onset of depression are not fully understood.
METHODS: In this study, we enrolled 66 patients with MDD and 31 healthy controls who underwent resting-state fMRI scans and neuropsychological assessments. We employed multivariate linear regression to examine the neural associations of CM and depression, specifically focusing on the bilateral occipital functional connectivity (OFC) networks relevant to MDD. Subsequently, a two-step mediation analysis was conducted to assess whether the OFC network mediated the relationship between CM experiences and the severity of depression.
RESULTS: Our study showed that patients with MDD exhibited reduced OFC strength, particularly in the occipito-temporal, parietal, and premotor regions. These reductions were negatively correlated with CM scores and the severity of depression. Notably, the overlapping regions in the bilateral OFC networks, affected by both CM experiences and depressive severity, were primarily observed in the bilateral cuneus, left angular and calcarine, as well as the right middle frontal cortex and superior parietal cortex. Furthermore, the altered strengths of the OFC networks were identified as positive mediators of the impact of CM history on depression symptoms in patients with MDD.
CONCLUSIONS: We have demonstrated that early exposure to CM may increase vulnerability to depression by influencing the brain\'s network. These findings provide new insights into understanding the pathological mechanism underlying depressive symptoms induced by CM.

OBJECTIVE: This study was to systematically assess the occipital lobe gray and white matter volume of isolated ventriculomegaly (IVM) fetuses with MRI and to follow up the neurodevelopment of participants.
METHODS: MRI was used to evaluate 37 IVM fetuses and 37 control fetuses. The volume of gray and white matter in each fetal occipital gyrus was manually segmented and compared, and neurodevelopment was followed up and assessed in infancy and early childhood.
RESULTS: Compared with the control group, the volume of gray matter in occipital lobe increased in the IVM group, and the incidence of neurodevelopmental delay increased.
CONCLUSIONS: We tested the hypothesis that prenatal diagnosis IVM represents a biological marker for development in fetal occipital lobe. Compared with the control group, the IVM group showed differences in occipital gray matter development and had a higher risk of neurodevelopmental delay.

During aging, the brain is subject to greater oxidative stress (OS), which is thought to play a critical role in cognitive impairment. Glutathione (GSH), as a major antioxidant in the brain, can be used to combat OS. However, how brain GSH levels vary with age and their associations with cognitive function is unclear. In this study, we combined point-resolved spectroscopy and edited spectroscopy sequences to investigate extended and closed forms GSH levels in the anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and occipital cortex (OC) of 276 healthy participants (extended form, 166 females, age range 20-70 years) and 15 healthy participants (closed form, 7 females, age range 26-56 years), and examined their relationships with age and cognitive function. The results revealed decreased extended form GSH levels with age in the PCC among 276 participants. Notably, the timecourse of extended form GSH level changes in the PCC and ACC differed between males and females. Additionally, positive correlations were observed between extended form GSH levels in the PCC and OC and visuospatial memory. Additionally, a decreased trend of closed form GSH levels with age was also observed in the PCC among 15 participants. Taken together, these findings enhance our understanding of the brain both closed and extended form GSH time course during normal aging and associations with sex and memory, which is an essential first step for understanding the neurochemical underpinnings of healthy aging.

UNASSIGNED: Driving is a complex skill involving various cognitive activities. Previous research has explored differences in the brain structures related to the navigational abilities of drivers compared to non-drivers. However, it remains unclear whether changes occur in the structures associated with low-level sensory and higher-order cognitive abilities in drivers.
UNASSIGNED: Gray matter volume, assessed via voxel-based morphometry analysis of T1-weighted images, is considered a reliable indicator of structural changes in the brain. This study employs voxel-based morphological analysis to investigate structural differences between drivers (n = 22) and non-drivers (n = 20).
UNASSIGNED: The results indicate that, in comparison to non-drivers, drivers exhibit significantly reduced gray matter volume in the middle occipital gyrus, middle temporal gyrus, supramarginal gyrus, and cerebellum, suggesting a relationship with driving-related experience. Furthermore, the volume of the middle occipital gyrus, and middle temporal gyrus, is found to be marginally negative related to the years of driving experience, suggesting a potential impact of driving experience on gray matter volume. However, no significant correlations were observed between driving experiences and frontal gray matter volume.
UNASSIGNED: These findings suggest that driving skills and experience have a pronounced impact on the cortical areas responsible for low-level sensory and motor processing. Meanwhile, the influence on cortical areas associated with higher-order cognitive function appears to be minimal.

OBJECTIVE: We sought to use the fractional amplitude of low-frequency fluctuation (fALFF) method to investigate the changes in spontaneous brain activity in CSM patients and their relationships with clinical features.
METHODS: We recruited 20 patients with CSM, and 20 healthy controls (HCs) matched for age, sex, and education status. The fALFF method was used to evaluate the altered spontaneous brain activities. The Pearson correlation analysis of fALFF and the clinical features were carried out.
RESULTS: Compared with HC, CSM group showed increased fALFF values in the left middle frontal gyrus, inferior parietal lobule, and right angular gyrus. Decreased fALFF values were found in the right lingual gyrus, cuneus (P < 0.05). Pearson correlation analysis shows that the fALFF values of all CSM were positively correlated with JOA score in the right angular gyrus (r = 0.518, P < 0.05).
CONCLUSIONS: CSM patients have abnormal fALFF distribution in multiple brain regions and might be an appealing alternative approach for further exploration of the pathological and neuropsychological states in CSM.

Although it has been established that cross-modal activations occur in the occipital cortex during auditory processing among congenitally and early blind listeners, it remains uncertain whether these activations in various occipital regions reflect sensory analysis of specific sound properties, non-perceptual cognitive operations associated with active tasks, or the interplay between sensory analysis and cognitive operations. This fMRI study aimed to investigate cross-modal responses in occipital regions, specifically V5/MT and V1, during passive and active pitch perception by early blind individuals compared to sighted individuals. The data showed that V5/MT was responsive to pitch during passive perception, and its activations increased with task complexity. By contrast, widespread occipital regions, including V1, were only recruited during two active perception tasks, and their activations were also modulated by task complexity. These fMRI results from blind individuals suggest that while V5/MT activations are both stimulus-responsive and task-modulated, activations in other occipital regions, including V1, are dependent on the task, indicating similarities and differences between various visual areas during auditory processing.