Switching off: disruptive TMS reveals distinct contributions of the posterior middle temporal gyrus and angular gyrus to bilingual speech production.

The role of the left temporoparietal cortex in speech production has been extensively studied during native language processing, proving crucial in controlled lexico-semantic retrieval under varying cognitive demands. Yet, its role in bilinguals, fluent in both native and second languages, remains poorly understood. Here, we employed continuous theta burst stimulation to disrupt neural activity in the left posterior middle-temporal gyrus (pMTG) and angular gyrus (AG) while Italian-Friulian bilinguals performed a cued picture-naming task. The task involved between-language (naming objects in Italian or Friulian) and within-language blocks (naming objects ["knife"] or associated actions ["cut"] in a single language) in which participants could either maintain (non-switch) or change (switch) instructions based on cues. During within-language blocks, cTBS over the pMTG entailed faster naming for high-demanding switch trials, while cTBS to the AG elicited slower latencies in low-demanding non-switch trials. No cTBS effects were observed in the between-language block. Our findings suggest a causal involvement of the left pMTG and AG in lexico-semantic processing across languages, with distinct contributions to controlled vs. "automatic" retrieval, respectively. However, they do not support the existence of shared control mechanisms within and between language(s) production. Altogether, these results inform neurobiological models of semantic control in bilinguals.

The critical mediating roles of the middle temporal gyrus and ventrolateral prefrontal cortex in the dynamic processing of interpersonal emotion regulation.

Interpersonal emotion regulation (IER) is a crucial ability for effectively recovering from negative emotions through social interaction. It has been emphasized that the empathy network, cognitive control network, and affective generation network sustain the deployment of IER. However, the temporal dynamics of functional connectivity among these networks of IER remains unclear. This study utilized IER task-fMRI and sliding window approach to examine both the stationary and dynamic functional connectivity (dFC) of IER. Fifty-five healthy participants were recruited for the present study. Through clustering analysis, four distinct brain states were identified in dFC. State 1 demonstrated situation modification stage of IER, with strong connectivity between affective generation and visual networks. State 2 exhibited pronounced connectivity between empathy network and both cognitive control and affective generation networks, reflecting the empathy stage of IER. Next, a 'top-down' pattern is observed between the connectivity of cognitive control and affective generation networks during the cognitive control stage of state 3. The affective response modulation stage of state 4 mainly involved connections between empathy and affective generation networks. Specifically, the degree centrality of the left middle temporal gyrus (MTG) mediated the association between one's IER tendency and the regulatory effects in state 2. The betweenness centrality of the left ventrolateral prefrontal cortex (VLPFC) mediated the association between one's IER efficiency and the regulatory effects in state 3. Altogether, these findings revealed that dynamic connectivity transitions among empathy, cognitive control, and affective generation networks, with the left VLPFC and MTG playing dominant roles, evident across the IER processing.

Microglial proliferation and astrocytic protein alterations in the human Huntington's disease cortex.

Huntington's disease (HD) is a neurodegenerative disorder that severely affects the basal ganglia and regions of the cerebral cortex. While astrocytosis and microgliosis both contribute to basal ganglia pathology, the contribution of gliosis and potential factors driving glial activity in the human HD cerebral cortex is less understood. Our study aims to identify nuanced indicators of gliosis in HD which is challenging to identify in the severely degenerated basal ganglia, by investigating the middle temporal gyrus (MTG), a cortical region previously documented to demonstrate milder neuronal loss. Immunohistochemistry was conducted on MTG paraffin-embedded tissue microarrays (TMAs) comprising 29 HD and 35 neurologically normal cases to compare the immunoreactivity patterns of key astrocytic proteins (glial fibrillary acidic protein, GFAP; inwardly rectifying potassium channel 4.1, Kir4.1; glutamate transporter-1, GLT-1; aquaporin-4, AQP4), key microglial proteins (ionised calcium-binding adapter molecule-1, IBA-1; human leukocyte antigen (HLA)-DR; transmembrane protein 119, TMEM119; purinergic receptor P2RY12, P2RY12), and indicators of proliferation (Ki-67; proliferative cell nuclear antigen, PCNA). Our findings demonstrate an upregulation of GFAP+ protein expression attributed to the presence of more GFAP+ expressing cells in HD, which correlated with greater cortical mutant huntingtin (mHTT) deposition. In contrast, Kir4.1, GLT-1, and AQP4 immunoreactivity levels were unchanged in HD. We also demonstrate an increased number of IBA-1+ and TMEM119+ microglia with somal enlargement. IBA-1+, TMEM119+, and P2RY12+ reactive microglia immunophenotypes were also identified in HD, evidenced by the presence of rod-shaped, hypertrophic, and dystrophic microglia. In HD cases, IBA-1+ cells contained either Ki-67 or PCNA, whereas GFAP+ astrocytes were devoid of proliferative nuclei. These findings suggest cortical microgliosis may be driven by proliferation in HD, supporting the hypothesis of microglial proliferation as a feature of HD pathophysiology. In contrast, astrocytes in HD demonstrate an altered GFAP expression profile that is associated with the degree of mHTT deposition.

Transcranial direct current stimulation over the left posterior temporal lobe modulates semantic control: Evidence from episodic memory distortions.

Evidence accumulates to show that semantic cognition requires, in addition to semantic representations, control processes that regulate the accessibility and use of semantic knowledge in a task- and time-appropriate fashion. Semantic control has been recently proposed to rely on a distributed network that includes the posterior temporal cortex. Along these lines, recent meta-analyses of neuroimaging data and studies with patients suffering from semantic aphasia have suggested that the left posterior middle temporal gyrus (pMTG) is critically involved whenever situational context must constrain semantic retrieval. In the present experiment, we used transcranial direct current stimulation over the left posterior temporal lobe in an attempt to interfere with semantic control while participants performed a DRM task, a procedure for inducing conceptually-based false recognition that is contingent on both activation and control processes. Paralleling findings with patients suffering from brain damage restricted to the temporoparietal cortex, anodal stimulation (relative to sham stimulation) resulted in increased false recognition but intact true recognition. These findings fit well with the idea that the left pMTG is a key component of a semantic control network, the alteration of which results in memory performance that is affected by the intrusion of contextually-inappropriate semantic information.

Association between somatosensory sensitivity and regional gray matter volume in healthy young volunteers: a voxel-based morphometry study.

Two-point discrimination (2PD) test reflects somatosensory spatial discrimination ability, but evidence on the relationship between 2PD and cortical gray matter (GM) volume is limited. This study aimed to analyze the relationship between cortical GM volume and 2PD threshold in young healthy individuals and to clarify the characteristics of brain structure reflecting the individual differences in somatosensory function. 2PD was measured in 42 healthy (20 females) volunteers aged 20-32 years using a custom-made test system that can be controlled by a personal computer. The 2PD of the right index finger measured with this device has been confirmed to show good reproducibility. T1-weighted images were acquired using a 3-T magnetic resonance imaging scanner for voxel-based morphometry analysis. The mean 2PD threshold was 2.58 ± 0.54 mm. Whole-brain multiple regression analysis of the relationship between 2PD and GM volume showed that a lower 2PD threshold (i.e. better somatosensory function) significantly correlated with decreased GM volume from the middle temporal gyrus to the inferior parietal lobule (IPL) in the contralateral hemisphere. In conclusion, a lower GM volume in the middle temporal gyrus and IPL correlates with better somatosensory function. Thus, cortical GM volume may be a biomarker of somatosensory function.

Integration of event experiences to build relational knowledge in the human brain.

We investigated how the human brain integrates experiences of specific events to build general knowledge about typical event structure. We examined an episodic memory area important for temporal relations, anterior-lateral entorhinal cortex, and a semantic memory area important for action concepts, middle temporal gyrus, to understand how and when these areas contribute to these processes. Participants underwent functional magnetic resonance imaging while learning and recalling temporal relations among novel events over two sessions 1 week apart. Across distinct contexts, individual temporal relations among events could either be consistent or inconsistent with each other. Within each context, during the recall phase, we measured associative coding as the difference of multivoxel correlations among related vs unrelated pairs of events. Neural regions that form integrative representations should exhibit stronger associative coding in the consistent than the inconsistent contexts. We found evidence of integrative representations that emerged quickly in anterior-lateral entorhinal cortex (at session 1), and only subsequently in middle temporal gyrus, which showed a significant change across sessions. A complementary pattern of findings was seen with signatures during learning. This suggests that integrative representations are established early in anterior-lateral entorhinal cortex and may be a pathway to the later emergence of semantic knowledge in middle temporal gyrus.

Middle temporal gyrus approach to mesial temporal lobe tumours in children.

AIM OF THE STUDY: To assess whether the middle temporal gyrus (MTG) approach to mesial temporal lobe (MTL) tumours is an effective procedure for the treatment of epilepsy in children. CLINICAL RATIONALE FOR THE STUDY: MTL tumours are a common cause of drug-resistant epilepsy in children. There is as yet no consensus regarding their treatment. One possibility is resection via a MTG approach. MATERIAL AND METHODS: We assessed the medical records of patients treated at the Department of Neurosurgery, Children's Memorial Health Institute,Warsaw, Poland between 2002 and 2020. A prospectively maintained database including clinical, laboratory, and radiographic presentation, as well as pre- and post-operative course, was analysed. Patients with at least a one- -year follow-up were included. RESULTS: There were 14 patients aged 4-18 years who underwent a MTG approach for a MTL tumour. All presented with epileptic seizure, and none had neurological deficit on admission to hospital. Median follow-up was 2.5 years. Neuronavigation was used to adjust the approach, localise the temporal horn, and achieve radical resection of the tumour and the hippocampus. Gross total resection was performed in all cases. In most patients, histopathological examination revealed ganglioglioma. One patient had transient aphasia. Two patients developed hemiparesis after surgery, which later improved. One of them also experienced visual disturbances. Acute complications were more frequent in younger patients (p = 0.024). In all cases, MRI confirmed complete resection and there was no tumour recurrence during the follow-up period. 13/14 patients remained seizure-free (Engel class I). CONCLUSIONS AND CLINICAL IMPLICATIONS: The MTG approach to MTL tumours is an effective procedure for the treatment of epilepsy in children. It avoids removal of the lateral temporal lobe and poses only a minor risk of permanent neurological complications.

The cortical regions and white matter tracts underlying auditory comprehension in patients with primary brain tumor.

The comprehension of spoken language is one of the most essential language functions in humans. However, the neurological underpinnings of auditory comprehension remain under debate. Here we used multi-modal neuroimaging analyses on a group of patients with low-grade gliomas to localize cortical regions and white matter tracts responsible for auditory language comprehension. Region-of-interests and voxel-level whole-brain analyses showed that cortical areas in the posterior temporal lobe are crucial for language comprehension. The fiber integrity assessed with diffusion tensor imaging of the arcuate fasciculus and the inferior longitudinal fasciculus was strongly correlated with both auditory comprehension and the grey matter volume of the inferior temporal and middle temporal gyri. Together, our findings provide direct evidence for an integrated network of auditory comprehension whereby the superior temporal gyrus and sulcus, the posterior parts of the middle and inferior temporal gyri serve as auditory comprehension cortex, and the arcuate fasciculus and the inferior longitudinal fasciculus subserve as crucial structural connectivity. These findings provide critical evidence on the neural underpinnings of language comprehension.

High-definition transcranial direct current stimulation (HD-tDCS) of the left middle temporal gyrus (LMTG) improves mathematical reasoning.

The role of the visuospatial network in mathematical processing has been established, but the role of the semantic neural network in mathematical processing is still poorly understood. The current study used high-definition transcranial direct current stimulation (HD-tDCS) to examine whether the semantic network supports mathematical processing. Using a single-blind, randomized, sham-controlled experimental design, 48 participants were randomly assigned to receive either anodal or sham HD-tDCS on the left middle temporal gyrus (LMTG), a core region of the semantic network. A number series completion task was used to measure mathematical reasoning and an arithmetical computation task was used as a control condition. Both tasks were administered before and after the 20 min HD-tDCS. The results showed that anodal HD-tDCS on the LMTG enhanced performance on the number series completion task, but not on the arithmetical computation task. Trial-level analysis further showed greater improvement at the more difficult problems of the number series completion task. These results demonstrate that the semantic network plays an important role in mathematical processing.

TMS Reveals Dynamic Interaction between Inferior Frontal Gyrus and Posterior Middle Temporal Gyrus in Gesture-Speech Semantic Integration.

Semantic processing is an amodal process with modality-specific information integrated in supramodal "convergence zones" or "semantic hub" with executive mechanisms that tailor semantic representation in a task-appropriate way. One unsolved question is how frontal control region dynamically interacts with temporal representation region in semantic integration. The present study addressed this issue by using inhibitory double-pulse transcranial magnetic stimulation over the left inferior frontal gyrus (IFG) or left posterior middle temporal gyrus (pMTG) in one of eight 40 ms time windows (TWs) (3 TWs before and 5 TWs after the identification point of speech), when human participants (12 females, 14 males) were presented with semantically congruent or incongruent gesture-speech pairs but merely identified the gender of speech. We found a TW-selective disruption of gesture-speech integration, indexed by the semantic congruency effect (i.e., a cost of reaction time because of semantic conflict), when stimulating the left pMTG in TW1, TW2, and TW7 but when stimulating the left IFG in TW3 and TW6. Based on the timing relationship, we hypothesize a two-stage gesture-speech integration circuit with a pMTG-to-IFG sequential involvement in the prelexical stage for activating gesture semantics and top-down constraining the phonological processing of speech. In the postlexical stage, an IFG-to-pMTG feedback signal might be implicated for the control of goal-directed representations and multimodal semantic unification. Our findings provide new insights into the dynamic brain network of multimodal semantic processing by causally revealing the temporal dynamics of frontal control and temporal representation regions.SIGNIFICANCE STATEMENT Previous research has identified differential functions of left inferior frontal gyrus (IFG) and posterior middle temporal gyrus (pMTG) in semantic control and semantic representation, respectively, and a causal contribution of both regions in gesture-speech integration. However, it remains largely unclear how the two regions dynamically interact in semantic processing. By using double-pulse transcranial magnetic stimulation to disrupt regional activity at specific time, this study for the first time revealed critical time windows when the two areas were causally involved in integrating gesture and speech semantics. Findings suggest a pMTG-IFG-pMTG neurocircuit loop in gesture-speech integration, which deepens current knowledge and inspires future investigation of the temporal dynamics and cognitive processes of the amodal semantic network.

N-terminal mutant huntingtin deposition correlates with CAG repeat length and symptom onset, but not neuronal loss in Huntington's disease.

Huntington's disease (HD) is caused by a CAG repeat expansion mutation in the gene encoding the huntingtin (Htt) protein, with mutant Htt protein subsequently forming aggregates within the brain. Mutant Htt is a current target for novel therapeutic strategies for HD, however, the lack of translation from preclinical research to disease-modifying treatments highlights the need to improve our understanding of the role of Htt protein in the human brain. This study aims to undertake an immunohistochemical screen of 12 candidate antibodies against various sequences along the Htt protein to characterize Htt distribution and expression in post-mortem human brain tissue microarrays (TMAs). Immunohistochemistry was performed on middle temporal gyrus TMAs comprising of up to 28 HD and 27 age-matched control cases, using 12 antibodies specific to various sequences along the Htt protein. From this study, six antibodies directed to the Htt N-terminus successfully immunolabeled human brain tissue. Htt aggregates and Htt protein expression levels for the six successful antibodies were subsequently quantified with a customized automated image analysis pipeline on the TMAs. A 2.5-12 fold increase in the number of Htt aggregates were detected in HD cases using antibodies MAB5374, MW1, and EPR5526, despite no change in overall Htt protein expression compared to control cases, suggesting a redistribution of Htt into aggregates in HD. MAB5374, MW1, and EPR5526 Htt aggregate numbers were positively correlated with CAG repeat length, and negatively correlated with the age of symptom onset in HD. However, the number of Htt aggregates did not correlate with the degree of striatal degeneration or the degree of cortical neuron loss. Together, these results suggest that longer CAG repeat lengths correlate with Htt aggregation in the HD human brain, and greater Htt cortical aggregate deposition is associated with an earlier age of symptom onset in HD. This study also reinforces that antibodies MAB5492, MW8, and 2B7 which have been utilized to characterize Htt in animal models of HD do not specifically immunolabel Htt aggregates in HD human brain tissue exclusively, thereby highlighting the need for validated means of Htt detection to support drug development for HD.

The local neural markers of MRI in patients with temporal lobe epilepsy presenting ictal panic: A resting resting-state postictal fMRI study.

OBJECTIVES: Temporal lobe epilepsy (TLE) is one of the most common focal epilepsies. Some patients with TLE have ictal panic (IP), which is often confused with panic attack (PA) in panic disorder (PD). Previous studies have described temporal lobe epilepsy with ictal panic (TLEIP), but the specific mechanisms remain unclear. Here, we used resting-state functional magnetic resonance imaging (rs-fMRI) to investigate local brain abnormalities in patients with TLEIP and tried to find neural markers to explore the mechanism of IP in patients with TLE. METHODS: A total of 40 patients with TLE, including 28 patients with TLE and 12 patients with TLEIP along with 30 age- and gender-matched healthy controls were included. We collected clinical/physiological/neuropsychological and rs-fMRI data. Fractional amplitude of low-frequency fluctuation (fALFF), regional homogeneity (ReHo), and degree centrality (DC) were calculated. ANOVA was used to find different areas and t-tests used to compare differences among fALFF, ReHo, and DC. Correlation analyses explored the relationship between local brain abnormalities and patient characteristics. RESULTS: No significant differences in age and gender were found among the three groups, nor were there differences in education level, Montreal Cognitive Assessment (MOCA) and Hamilton Anxiety Scale (HAMA) between the TLEIP and TLE groups. All the onset sites of patients with TLEIP were on the right. In addition to fear, other symptoms observed included nausea, palpitations, rising epigastric sensation, and dyspnea. There were no correlations between duration of IP and HAMA (p = 0.659). Moreover, all IP durations were <2 min and most <1 min. Compared to the HCs group, the ReHo value of the TLEIP group in the right middle frontal gyrus was significantly decreased (GRF correction, two-tailed, voxel level P < 0.005, cluster level P < 0.05). Compared to the HCs and TLE groups, the DC value of the TLEIP group in the left middle temporal gyrus (MTG) was significantly increased (GRF correction, two-tailed, voxel level P < 0.005, cluster level P < 0.05). No regions showed any significant fALFF difference between HCs and TLE groups (GRF correction, two-tailed, voxel level P < 0.005, cluster level P < 0.05). CONCLUSIONS: This research describes local brain abnormalities in patients with TLE presenting as IP. These results will be preliminarily conducive to understand the seizure mechanism of IP in patients with TLE, find out the MRI neural markers, and to further explore the neurophysiological mechanisms of IP in patients with TLE.

Transformation of Event Representations along Middle Temporal Gyrus.

When learning about events through visual experience, one must not only identify which events are visually similar but also retrieve those events' associates-which may be visually dissimilar-and recognize when different events have similar predictive relations. How are these demands balanced? To address this question, we taught participants the predictive structures among four events, which appeared in four different sequences, each cued by a distinct object. In each, one event ("cause") was predictably followed by another ("effect"). Sequences in the same relational category had similar predictive structure, while across categories, the effect and cause events were reversed. Using functional magnetic resonance imaging data, we measured "associative coding," indicated by correlated responses between effect and cause events; "perceptual coding," indicated by correlated responses to visually similar events; and "relational category coding," indicated by correlated responses to sequences in the same relational category. All three models characterized responses within the right middle temporal gyrus (MTG), but in different ways: Perceptual and associative coding diverged along the posterior to anterior axis, while relational categories emerged anteriorly in tandem with associative coding. Thus, along the posterior-anterior axis of MTG, the representation of the visual attributes of events is transformed to a representation of both specific and generalizable relational attributes.

Emotional intelligence mediates the association between middle temporal gyrus gray matter volume and social anxiety in late adolescence.

As a common mental health problem, social anxiety refers to the fear and avoidance of interacting in social or performance situations, which plays a crucial role in many health and social problems. Although a growing body of studies has explored the neuroanatomical alterations related to social anxiety in clinical patients, far fewer have examined the association between social anxiety and brain morphology in the general population, which may help us understand the neural underpinnings of social anxiety more comprehensively. Here, utilizing a voxel-based morphometry approach via structural magnetic resonance imaging, we investigated brain gray matter correlates of social anxiety in 231 recent graduates of the same high school grade. We found that social anxiety was positively associated with gray matter volume in the right middle temporal gyrus (MTG), which is a core brain area for cognitive processing of emotions and feelings. Critically, emotional intelligence mediated the impact of right MTG volume on social anxiety. Notably, our results persisted even when controlling for the effects of general anxiety and depression. Altogether, our research reveals right MTG gray matter volume as a neurostructural correlate of social anxiety in a general sample of adolescents and suggests a potential indirect effect of emotional intelligence on the association between gray matter volume and social anxiety.

Higher BMI is associated with smaller regional brain volume in older adults with type 2 diabetes.

AIMS/HYPOTHESIS: There are established relationships between adiposity (obesity) and higher dementia risk, faster cognitive decline and associated neural injury. Type 2 diabetes is strongly linked to greater adiposity and has been consistently associated with neural injury and poor cognitive outcomes. However, although obesity is a major cause of type 2 diabetes, there is limited evidence on the association of adiposity with brain atrophy among individuals with type 2 diabetes. METHODS: We examined the association of BMI (a measure of adiposity), and of long-term trajectories of BMI (three empirically identified groups of trajectories-'normal', 'overweight' and 'obese'-using SAS macro PROC TRAJ), with regional brain volume, in a sample of older individuals (aged 64-84) with type 2 diabetes participating in the Israel Diabetes and Cognitive Decline Study (n = 198). RESULTS: Using linear regression, we found that greater BMI was associated with smaller volumes of the inferior frontal gyrus (IFG) (r = -0.25, p = 0.001) and the middle temporal gyrus (r = -0.19; p = 0.010) after adjusting for sociodemographic covariates and total intracranial volume. In addition, there were significant differences between BMI trajectory groups in IFG volume (F = 4.34, p = 0.014), such that a long-term trajectory of obesity was associated with a smaller volume. Additional adjustment for cardiovascular and diabetes-related potential confounders did not substantively alter the results. There were no associations of adiposity with superior frontal gyrus, middle frontal gyrus or total grey matter volumes. CONCLUSIONS/INTERPRETATION: In older adults with type 2 diabetes, long-term adiposity may have a detrimental impact on volume of brain regions relevant to cognitive functioning. Further studies to identify the underlying mechanisms are warranted. Graphical abstract.

The function of the hippocampus and middle temporal gyrus in forming new associations and concepts during the processing of novelty and usefulness features in creative designs.

Creative thought relies on the reorganization of existing knowledge to generate novel and useful concepts. However, how these new concepts are formed, especially through the processing of novelty and usefulness (which are usually regarded as the key properties of creativity), is not clear. Taking familiar and useful (FU) objects/designs as the starting point or fundamental baseline, we modified them into novel and useless (NS) objects/designs or novel and useful (NU) ones (i.e., truly creative ones) to investigate how the features of novelty and usefulness are processed (processing of novelty: NU minus FU; processing of usefulness: NU minus NS). Specifically, we predicted that the creative integration of novelty and usefulness entails not only the formation of new associations, which could be critically mediated by the hippocampus and adjacent medial temporal lobe (MTL) areas, but also the formation of new concepts or categories, which is supported by the middle temporal gyrus (MTG). We found that both the MTL and the MTG were involved in the processing of novelty and usefulness. The MTG showed distinctive patterns of information processing, reflected by strengthened functional connectivity with the hippocampus to construct new concepts and strengthened functional connectivity with the executive control system to break the boundaries of old concepts. Additionally, participants' subjective evaluations of concept distance showed that the distance between the familiar concept (FU) and the successfully constructed concept (NU) was larger than that between the FU and the unsuccessfully constructed concept (NS), and this pattern was found to correspond to the patterns of their neural representations in the MTG. These findings demonstrate the critical mechanism by which new associations and concepts are formed during novelty and usefulness processing in creative design; this mechanism may be critically mediated by the hippocampus-MTG connection.

The function of medial temporal lobe and posterior middle temporal gyrus in forming creative associations.

Although the function of the hippocampus and adjacent medial temporal lobe (MTL) areas in forming associations is generally recognized, how MTL contributes to form creative associations that could result in novel and appropriate functions or meanings remains unclear. In this study, we compared highly creative combinations (HCCs) of two objects (e.g., that of "lifejacket" and "distress signal device") that resulted in genuine innovative designs comprising additionally unprecedented functions (the "1 + 1 > 2" effects) with the lowly creative combinations (LCCs, e.g., the combination of "set-top box" and "jewelry box") that resulted in nothing more than simple "1 + 1 = 2" effects. The event-related functional magnetic resonance imaging (fMRI) study found that during the "early binding phase," when the combinations of the two objects were initially encoded, the right parahippocampus was more intensively activated during the encoding of HCC relative to LCC trials. However, during the "late integration phase," when participants finally formed a holistic mental representation of new products based on the two-object combinations, both HCCs and LCCs were found to be associated with significantly increased hippocampal and parahippocampal activation relative to the baseline condition, but at a similar level. In this "late integration phase," the functional areas appeared to be more intensively activated in HCCs relative to LCCs located in the posterior middle temporal gyrus (pMTG), the area known to mediate category-related processing. Consistently, our supplementary behavioral study found that, relative to LCCs, HCCs had a higher possibility of resulting in some new conceptual expansions that differed from each of the original two objects that constituted the combinations. These findings indicate that the formation of creative combinations not only require MTL-based novel association-formation, but also pMTG-based novel concept-expansion.

Selective Functional Hyperconnectivity in the Middle Temporal Gyrus Subregions in Lifelong Premature Ejaculation.

BACKGROUND: Lifelong premature ejaculation (LPE) has been linked to altered brain function and structure. Although the middle temporal gyrus (MTG) is consistently more affected in LPE, its functional and structural changes have yet to be determined at the subregional level. AIM: To explore the functional and structural changes of MTG in LPE at the subregional level based on a combined analysis of multimodal magnetic resonance imaging data. METHODS: 25 patients with LPE and 21 healthy controls underwent resting-state functional and structural magnetic resonance imaging scans. The MTG was parcellated into the anterior part of the MTG (aMTG), middle part of the MTG, posterior part of the MTG, and sulcus part of the MTG. Resting-state functional connectivity (rsFC) and gray matter volume (GMV) of each MTG subregion were calculated and compared between the 2 groups. OUTCOMES: The functional and structural changes of MTG at the subregional level were assessed in patients with LPE and controls, as well as the correlation of them with premature ejaculation diagnostic tool and Beck Depression Inventory. RESULTS: Despite similar rsFC patterns of each MTG subregion in both groups, quantitative comparison analyses revealed that patients with LPE showed increased rsFC between the left aMTG and the right cuneus (0.34 ± 0.12 vs 0.17 ± 0.17), between the right aMTG and the right parahippocampal gyrus (0.36 ± 0.16 vs 0.15 ± 0.10), and between the right middle MTG and the left MTG (0.40 ± 0.14 vs 0.18 ± 0.15) relative to controls (P < .05, cluster-level family-wise error corrected). Moreover, validation analyses revealed that these results remained significant after adjusting for depression. However, there were no significant group differences in GMV in all the MTG subregions (P > .05, Bonferroni corrected). In addition, no significant correlations between rsFC and GMV of the MTG subregions and the clinical variables were found in patients with LPE (P > .05, Bonferroni corrected). CLINICAL IMPLICATIONS: Functional hyperconnectivity in the MTG subregions may facilitate a more sophisticated understanding of the neuropathological mechanism underlying LPE. STRENGTHS AND LIMITATIONS: There are no previous studies examining functional and structural changes in LPE at the MTG subregional level. The main limitation is the small sample size. CONCLUSIONS: We present evidence that individuals with LPE have a selective functional hyperconnectivity yet preserved structural integrity in the MTG subregions, which may facilitate a more sophisticated understanding of the neuropathological mechanism underlying LPE by highlighting the critical role of the MTG in this disorder. Zhang T, Tang D, Cai H, et al. Selective Functional Hyperconnectivity in the Middle Temporal Gyrus Subregions in Lifelong Premature Ejaculation. J Sex Med 2020;17:1457-1466.

Selective impairment of On-reading (Chinese-style pronunciation) in alexia with agraphia for kanji due to subcortical hemorrhage in the left posterior middle temporal gyrus.

We report a patient with alexia with agraphia for kanji after hemorrhage in the left posterior middle temporal gyrus. The results of single-character kanji reading and two-character on- (Chinese-style pronunciation), kun- (native Japanese pronunciation), and Jukujikun (irregular kun-) reading word tests revealed that the patient could not read kanji characters with on-reading but read the characters with kun-reading. We consider that this on-reading alexia was caused by disconnection between the posterior inferior temporal cortex (orthographic lexicon) and the posterior superior temporal gyrus (phonological lexicon), and preserved kun- and Jukujikun-reading was realized by bypassing the orthography-to-phonology route by the semantic route.

Functional and resting-state characterizations of a periventricular heterotopic nodule associated with epileptogenic activity.

The object of this study was to extensively characterize a region of periventricular nodular heterotopia (PVNH) in an epilepsy patient to reveal its possible neurocognitive functional role(s). The authors used 3-T MRI approaches to exhaustively characterize a single, right hemisphere heterotopion in a high-functioning adult male with medically responsive epilepsy, which had manifested during late adolescence. The heterotopion proved to be spectroscopically consistent with a cortical-like composition and was interconnected with nearby ipsilateral cortical fundi, as revealed by fiber tractography (diffusion-weighted imaging) and resting-state functional connectivity MRI (rsfMRI). Moreover, the region of PVNH demonstrated two novel characterizations for a heterotopion. First, functional MRI (fMRI), as distinct from rsfMRI, showed that the heterotopion was significantly modulated while the patient watched animated video scenes of biological motion (i.e., cartoons). Second, rsfMRI, which demonstrated correlated brain activity during a task-negative state, uniquely showed directionality within an interconnected network, receiving positive path effects from patent cortical and cerebellar foci while outputting only negative path effects to specific brain foci.These findings are addressed in the context of the impact on noninvasive presurgical brain mapping strategies for adult and pediatric patient workups, as well as the impact of this study on an understanding of the functional cortical architecture underlying cognition from a neurodiversity and evolutionary perspective.