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Motivation: Mechanisms underlying the variation in the appearance of electroencephalogram (EEG) over human head are not well characterized. We hypothesized that spatial variation of the EEG, being ...

Background: Currently the most favorable single stage procedure for management of long segment anterior urethral stricture is dorsal onlay technique of urethroplasty. This required circumferential extensive mobilization of the urethra, which might cause ischemia of urethra in addition to chordee. To evaluate the short term outcome of dorsolateral onlay BMG (Buccal Mucosal Graft) urethroplasty by unilateral urethral mobilization for treatment of long segment anterior urethral stricture Materials and methods: A prospective experimental study from January 2016 to December 2018 is carried out in Department of Urology, Chittagong Medical College Hospital (CMCH) Chattogram, Bangladesh. Total 32 patients of long segment anterior urethral stricture were treated by dorsolateral onlay BMG urethroplasty by unilateral urethral mobilization. Stricture >2cm were included; RGU, MCU and Uroflowmetry were the mainstay of assessment. Success was defined as maximum flow rate >15 ml/s, normal RGU and/ urethroscopy. Failure considered as presence of obstructive symptoms, Qmax < 15 ml/s, stricture on RGU and any post-operative urethral intervention. Results: Mean stricture length was 48.72mm (Range: 30-77mm) and mean follow up time was 22.4months (Range: 12-40 months). Three patients were found to develop stricture at proximal anastomotic site during follow up and required optical internal urethrotomy and considered as failure. 01 patients developed Surgical Site Infection (SSI) which resolved after regular dressing. Success rate was 90.7% Conclusion: Dorsolateral onlay BMG urethroplasty by unilateral mobilization is feasible, safe and easily adoptable for long segment anterior urethral stricture with good short term outcome. Chatt Maa Shi Hosp Med Coll J; Vol.20 (2); July 2021; Page 14-17

What role do cognitive control regions like the dorsolateral prefrontal cortex (dlPFC) play in normative behavior (e.g., generosity, healthy eating)? Some models suggest that dlPFC activation during normative choice reflects the use of control to overcome default hedonistic preferences. Here, we develop an alternative account, showing that an attribute-based neural drift diffusion model (anDDM) predicts trial-by-trial variation in dlPFC response across three fMRI studies and two self-control contexts (altruistic sacrifice and healthy eating). Using the anDDM to simulate a variety of self-control dilemmas generated a novel prediction: although dlPFC activity might typically increase for norm-consistent choices, deliberate self-regulation focused on normative goals should decrease or even reverse this pattern (i.e., greater dlPFC response for hedonic, self-interested choices). We confirmed these predictions in both altruistic and dietary choice contexts. Our results suggest that dlPFC response during normative choice may depend more on value-based evidence accumulation than inhibition of our baser instincts.

Brain stem abscesses are rare entities that predominantly affect the pons. A wide variety of microorganisms may be implied, depending on the focus of dissemination. We present the case of a female patient with multiple comorbidities who developed multi-lobar pneumonia due to influenza A(H1N1)pdm09 virus during the postoperative period after an emergent cholecystectomy, requiring mechanical ventilation (MV). Following clinical improvement and withdrawal of MV, the patient did not recover consciousness. Forty-eight hours later, imaging exams showed an abscess in the left pontine dorsolateral tegmentum –a region recently associated with coma-. Despite the administration of broad-spectrum antibiotics, the patient died five days later. This case illustrates the importance of considering pontine abscesses as a cause of poor neurological course in critically ill patients, as well as the need for doing imaging exams to rule out intracranial lesions, particularly in coma-associated areas.

We report an 87-year-old woman with right dorsolateral medullary hemorrhage. She did not show all of the usual symptoms of Wallenberg syndrome and her main symptom was severe dysphagia. Dorsolateral medullary hemorrhage may be overlooked, because it is rare and does not exhibit the typical Wallenberg syndrome presentation usually seen in patients with infarction at the dorsolateral medulla.

The prefrontal lobe has been considered to be closely related to depression. This study examined the relationship between depression and three prefronto-thalamic tract (PF-TT) regions (the dorsolateral prefronto-thalamic tract [DLPF-TT], ventrolateral prefronto-thalamic tract [VLPF-TT], and the orbitofronto-thalamic tract [OF-TT]) in patients with mild traumatic brain injury (TBI), using diffusion tensor tractography (DTT). Thirty-seven patients with depression following mild TBI were recruited based on Beck Depression Inventory-II (BDI-II) scores. Thirty-one normal control subjects were also recruited. The three regions of the PF-TTs were reconstructed using probabilistic tractography and DTT parameters for each of the three PF-TT regions were determined. The tract volume of the DLPF-TT and OF-TT in the patient group showed a significant decrease compared to that of the control group (p r = − 0.33) and left (r = − 0.41) DLPF-TT (p p > 0.05). Using DTT, depression was found to be closely related to a DLPF-TT injury in patients with mild TBI. We believe that evaluation of the DLPF-TT using DTT would be helpful when assessing patients with depression following mild TBI. These results can provide useful information regarding the proper application of neuromodulation in the management of depression.

This randomized crossover study investigated whether anodal transcranial direct current stimulation (tDCS) over the dorsolateral prefontal cortex (dlPFC) modulates memory-guided finger isometric maintenance during single motor and dual cognitive-motor tasks, based on electroencephalogram (EEG) signals. Twenty-three healthy participants (14 female; M age = 29.130 years, SD = 10.918) underwent both sham and 2-mA stimulation sessions over the dlPFC for 20 minutes, with a minimum washout period of seven days. We analyzed finger-force isometric maintenance and event-related spectral perturbation (ERSP) of the EEG during early and later phases of both tasks. We observed a significant motor accuracy improvement ( p = .014) and significant variation of force output ( p = .027) with significant decrease in ERSP on the dorsomedial prefrontal cortex (dmPFC) (early phase, p = .027; later phase, p = .023) only after 2 mA stimulation. Thus, anodal tDCS over the dlPFC may improve memory-guided force control during cognitive-motor dual tasks.

Sinus tarsi syndrome is the clinical syndrome of lateral heel pain with local tenderness at the sinus tarsi and is frequently associated with a history of inversion sprain to the ankle. The lateral heel pain can be due to the capsule-ligamentous structures lateral to the axis of the anterior and posterior subtalar joints. Anterior and posterior subtalar arthroscopies are needed to detect and treat the disorders of both joints. In this Technical Note, we describe the details of a 2-portal arthroscopic approach to both anterior and posterior subtalar joints. This allows complete examination of all the possible sources of lateral heel pain in sinus tarsi syndrome.

Objective: Despite effective psychological and pharmacological treatments, there is a large unmet burden of illness in post-traumatic stress disorder (PTSD). Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive intervention and a putative treatment strategy for PTSD. The evidence base to date suggests that rTMS targeting the dorsolateral prefrontal cortex (DLPFC), in particular the right DLPFC, leads to improvements in PTSD symptoms. However, optimal stimulation parameters have yet to be determined. In this study, we examine the efficacy of high- and low-frequency rTMS of the right DLPFC using a randomized, double-blind, sham-controlled design in civilian PTSD. Methods: We conducted a 2-week single-site randomized sham-controlled trial of rTMS targeting the right DLPFC. We recruited civilians aged 19 to 70 with PTSD and randomized subjects with allocation concealment to daily 1-Hz rTMS, 10-Hz rTMS, or sham rTMS. The primary outcome was improvement in Clinician Administered PTSD Scale–IV (CAPS-IV). Secondary outcomes included change in depressive and anxiety symptoms. Results: We recruited 31 civilians with PTSD. One 1-Hz-treated patient developed transient suicidal ideation. Analyses revealed significant improvement in CAPS-IV symptoms in the 1-Hz group relative to sham (Hedges’ g = −1.07) but not in the 10-Hz group. This was not attributable to changes in anxious or depressive symptomatology. Ten-Hz stimulation appeared to improve depressive symptoms compared to sham. Conclusion: Low-frequency rTMS is efficacious in the treatment of civilian PTSD. Our data suggest that high-frequency rTMS of the right DLPFC is worthy of additional investigation for the treatment of depressive symptoms comorbid with PTSD.

This study investigated whether time-estimation task exposure influences the severity of Attention Deficit Hyperactivity Disorder (ADHD), as well as theta band activity in the dorsolateral prefrontal cortex and ventrolateral prefrontal cortex.Twenty-two patients with ADHD participated in a crossover experiment with a visual time-estimation task under control conditions (without exposure to time estimation tasks) and experimental (thirty days exposure to time-estimation tasks) in association with electroencephalographic analysis of theta band.ADHD patients with thirty days of time-estimation task exposure presented a worse performance of the time-estimation task, as revealed by the measurements of the absolute error and relative error (We propose that the decrease in EEG theta power may indicate an efficient accumulation of temporal pulses, which could be responsible for the improvement in the patient cognitive aspects as demonstrated by the current study. Time-estimation task improves ADHD cognitive symptoms, with a substantial increase in cortical areas activity related to attention and memory, suggesting its use as a tool for cognitive timing function management and non-invasive therapeutic aid in ADHD.

As discussed in both the original study and the current chapter, the dorsolateral prefrontal cortex (DLPFC) is a required neural player in the aesthetic appraisal and a basic stage of the aesthetic experience. As the distinct activation that the authors found in the neuroimaging study occurred when participants rated as beautiful natural, artistic, and decorative stimuli, we concluded that left DLPFC responded to aesthetic qualities in general and not to specific artistic qualities. More recent studies indicate that the function of the LPFC in relation to aesthetics may be to exercise cognitive control to direct attention with a proper aesthetic orientation. Other studies suggest that LPFC is part of a frontal “evaluative” network which supports an analysis of emotional response and personal relevance. Specifically, left DLPFC seems to affect the evaluation of different images, disengaging from a habitual mode of identifying objects in order to adopt an aesthetic perspective.

The dorsolateral striatum (DLS) is involved in learning and executing procedural actions. Cell ensembles in the DLS, but not the dorsomedial striatum (DMS), exhibit a burst of firing at the start of a well-learned action sequence (“task-bracketing”). However, it is currently unclear what information is contained in these bursts. Some theories suggest that these bursts should represent the procedural action sequence itself (that they should be about future action chains), whereas others suggest that they should contain representations of the current state of the world, taking into account primarily past information. In addition, the DLS local field potential shows transient bursts of power in the 50 Hz range (γ50) around the time a learned action sequence is initiated. However, it is currently unknown how bursts of activity in DLS cell ensembles and bursts of γ50 power in the DLS local field potential are related to each other. We found that DLS bursts at lap initiation in rats represented recently experienced reward locations more than future procedural actions, indicating that task initiation DLS bursts contain primarily retrospective, rather than prospective, information to guide procedural actions. Furthermore, representations of past reward locations increased during periods of increased γ50 power in the DLS. There was no evidence of task initiation bursts, increased γ50 power, or retrospective reward location information in the neighboring dorsomedial striatum. These data support a role for the DLS in model-free theories of procedural decision-making over planned action-chain theories, suggesting that procedural actions derive from representations of the current and recent past. Significance Statement: While it is well-established that the dorsolateral striatum (DLS) plays a critical role in procedural decision-making, open questions remain about the kinds of representations contained in DLS ensemble activity that guide procedural actions. We found that DLS, but not DMS, cell ensembles contained nonlocal representations of past reward locations that appear moments before task initiation DLS bursts. These retrospective representations were temporally linked to a rise in γ50 power that also preceded the characteristic DLS burst at task initiation. The strength of both γ50 power and retrospective representations grew with experience. These results support models of procedural decision-making based on associations between available actions and the current state of the world over models based on planning over action-chains.

Background: Deep-brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment for motor symptoms of advanced Parkinson's disease (PD). Due to a lack of detailed somatotopic organization in STN, the clinically most effective part of the STN for stimulation has already become one of the hot research focuses. At present, there are some reports about topographic distribution for different depths within the STN, but few about a mediolateral topography in this area.Objective: The objective was to investigate the local field potential (LFP) distribution patterns in dorsomedial and dorsolateral subparts of STN.Methods: In total, 18 PD patients eventually enrolled in this study. The DBS electrodes were initially located on the lateral portion of dorsolateral STN. Because of internal capsule side effects presented at low threshold (below 1.5 mA), the electrode was reimplanted more medially to the dorsomedial STN. In this process, intraoperative LFPs from dorsomedial and dorsolateral STN were recorded from the inserted electrode. Both beta power and gamma power of the LFPs were calculated using the power spectral density (PSD) for each DBS contact pair. Furthermore, coherence between any two pairs of contacts was computed in the dorsomedial and dorsolateral parts of STN, respectively. Meanwhile, the Unified Parkinson's Disease Rating Scale part III (UPDRS-III) was monitored prior to surgery and at the 6-month follow-up.Results: Compared to the dorsolateral part of STN, gamma oscillations (p < 0.01) and coherence (p < 0.05) were all weaker in the dorsomedial part. However, no obvious differences in beta oscillations and coherence were observed between the two groups (p > 0.05). Moreover, it should be noted that DBS of the dorsomedial STN resulted in significant improvement in the UPDRS-III in PD patients. There was a 61.50 ± 21.30% improvement in UPDRS-III scores in Med-off/Stim-on state relative to the Med-off state at baseline (from 15.44 ± 6.84 to 43.94 ± 15.79, p < 0.01).Conclusions: The specific features of gamma activity may be used to differentiate STN subregions. Moreover, the dorsomedial part of STN might be a potential target for DBS in PD.

Two primary functions attributed to the hippocampus and prefrontal cortex (PFC) network are retaining the temporal and spatial associations of events and detecting deviant events. It is unclear, however, how these two functions converge into one mechanism. Here, we tested whether increased activity with perceiving salient events is a deviant detection signal or contains information about the event associations by reflecting the magnitude of deviance (i.e., event saliency). We also tested how the deviant detection signal is affected by the degree of anticipation. We studied regional neural activity when people watched a movie that had varying saliency of a novel or an anticipated flow of salient events. Using intracranial electroencephalography from 10 patients, we observed that high-frequency activity (50–150 Hz) in the hippocampus, dorsolateral PFC, and medial OFC tracked event saliency. We also observed that medial OFC activity was stronger when the salient events were anticipated than when they were novel. These results suggest that dorsolateral PFC and medial OFC, as well as the hippocampus, signify the saliency magnitude of events, reflecting the hierarchical structure of event associations.

The prefrontal cortex is deputed to higher functions, such as behavior and personality. It includes three regions: ventromedial, orbitofrontal, and dorsolateral. Each of them has a function. Devising, programming, and planning are all conditions related to the dorsolateral cortex, also responsible for rational content and decision. Damage to this region results in apathetic syndrome, a condition that causes loss of interest, initiative, and attention, and in the most severe cases leads to a lethargic state. It is also known as a form of secondary depression, the so-called pseudo-depression syndrome, according to Karl Kleist or apathetic-abulic-akinetic syndrome, according to Alexander Luria. The prefrontal dorsolateral syndrome is responsible for the reduction or abolition of free will. Free will is an expression of individual freedom. It allows the human being to have and express own opinions as well as to respect those of others. Free will is related to moral sense, a binomial which directs the individual towards a proper social conduct. In this review, we describe the effects of the pseudo-depression syndrome on free will, of which we treat both the anatomical site and the social aspect.

Repetitive transcranial magnetic stimulation (rTMS) is an effective treatment for refractory major depressive disorder, yet no studies have characterized trajectories of rTMS response. The aim of this study was to characterize response trajectories for patients with major depression undergoing left dorsolateral prefrontal cortex rTMS and to determine associated baseline clinical characteristics.This was a secondary analysis of a randomized noninferiority trial (N=388) comparing conventional 10-Hz rTMS and intermittent theta burst stimulation (iTBS) rTMS. Participants were adult outpatients who had a primary diagnosis of major depressive disorder, had a score ≥18 on the 17-item Hamilton Depression Rating Scale (HAM-D), and did not respond to one to three adequate antidepressant trials. Treatment was either conventional 10-Hz rTMS or iTBS rTMS applied to the dorsolateral prefrontal cortex, 5 days/week over 4-6 weeks (20-30 sessions). Group-based trajectory modeling was applied to identify HAM-D response trajectories, and regression techniques were used to identify associated characteristics.Four trajectories were identified: nonresponse (N=43, 11%); rapid response (N=73, 19%); higher baseline symptoms, linear response (N=118, 30%); and lower baseline symptoms, linear response (N=154, 40%). Significant differences in response and remission rates between trajectories were detectable by week 1. There was no association between treatment protocol and response trajectory. Higher baseline scores on the HAM-D and the Quick Inventory of Depression Symptomatology-Self-Report (QIDS-SR) were associated with the nonresponse trajectory, and older age, lower QIDS-SR score, and lack of benzodiazepine use were associated with the rapid response trajectory.Major depression shows distinct response trajectories to rTMS, which are associated with baseline clinical characteristics but not treatment protocol. These response trajectories with differential response to rTMS raise the possibility of developing individualized treatment protocols.

The dorsolateral subluxation index of the femoral head is a good proxy of hip dysplasia in dogs. An exploratory, prospective, descriptive study was carried out in order to assess whether the dorsolateral subluxation index may also be useful to improve diagnosis of hip dysplasia in cats. The dorsolateral subluxation index was determined by CT scans simulating the loading position, and compared with measurements of the Norberg-Olsson angle. A total of 82 cats were subjected to radiographic examination of the pelvis, in the standard ventro-dorsal projection, and to CT scans of the pelvis and hips. The Norberg-Olsson angle of each hip was calculated radiographically, while the dorsolateral subluxation index of the femur was calculated on CT images according to a technique recently developed for evaluation of hip dysplasia in dogs. Using the Norberg-Olsson angle a total of 52 hips (31,7%) were diagnosed as dysplastic, 74 (45,1%) as non-dysplastic, and 38 (23,1%) as borderline. Using the dorsolateral subluxation index, values ranged from a minimum of 34.6% to a maximum of 66.6% and four distribution classes were proposed. Findings indicated that the dorsolateral subluxation index previously described as method for quantifying hip dysplasia in dogs is also a feasible method for quantifying hip dysplasia in cats. Future studies are needed to more definitively determine the diagnostic sensitivity of this method.

Cynoglossus yokomaru sp. nov., previously known as Cynoglossus sp., called “Otafuku-genko” (the standard Japanese name), is described based on 15 specimens [64–226 mm in standard length (SL)] collected at depths of 73–157 m in the East China Sea and Yellow Sea. The new species belongs to the Cynoglossus kopsii complex as redefined in this paper and clearly differs from its congeners by the following combination of characters: two ocular-side lateral lines (dorsolateral and midlateral lines present, ventrolateral line absent); no blind-side lateral line; ctenoid scales present on both sides; two ocular-side nostrils; ocular-side posterior nostril immediately anterior to a point between eyes; head length (HL) shorter than its depth; posterior margin of upper jaw on ocular side not reaching below posterior margin of lower eye; body depth 25.8–30.2% SL; upper supraorbital length 35.5–47.3% HL; lower supraorbital length 48.8–64.3% HL; horizontal diameter of lower eye 10.1–17.4% HL; a long and continuous dorsolateral line with 61–70 scales; midlateral-line scales 4–5 + 65–68 = 69–73; scales above dorsolateral line 3–4; scales between dorsolateral line and midlateral line 10–12; cephalodorsal-line scales 8; dorsal-fin rays 115–119; anal-fin rays 90–94; caudal-fin rays 10 (rarely 8 or 9); and vertebrae 9 + 47–48 = 56–57.

Background: Alzheimer's disease (AD) animal models have shown a reduced gamma power in several brain areas, and induction of these oscillations by non-invasive methods has been shown to modify several pathogenic mechanisms of AD. In humans, the application of low-intensity magnetic fields has shown to be able to produce neural entrainment at the magnetic pulse frequency, making it useful to induce gamma frequencies.Objective: The aim of this study was to assess if the application of fast gamma magnetic stimulation (FGMS) over the left prefrontal dorsolateral cortex would be a safe and well-tolerated intervention that could potentially improve cognitive scores in subjects with mild cognitive impairment and mild AD.Methods: In these randomized, double-blind, sham-controlled study, participants were assigned to either receive daily sessions two times a day of active or sham FGMS for 6 months. Afterward, measurements of adverse effects, cognition, functionality, and depression were taken.Results: Thirty-four patients, 17 in each group, were analyzed for the primary outcome. FGMS was adequately tolerated by most of the subjects. Only four patients from the active FGMS group (23.52%) and one patient from the sham FGMS group (5.88%) presented any kind of adverse effects, showing no significant difference between groups. Nevertheless, FGMS did not significantly change cognitive, functionality, or depressive evaluations.Conclusion: FGMS over the left prefrontal dorsolateral cortex applied twice a day for 6 months resulted to be a viable intervention that can be applied safely directly from home without supervision of a healthcare provider. However, no statistically significant changes in cognitive, functionality, or depression scores compared to sham stimulation were observed.Clinical Trial Registration:www.ClinicalTrials.gov, Identifier: NCT03983655, URL: https://clinicaltrials.gov/ct2/show/NCT03983655.

Relapse is one of the most perplexing problems of addiction. The dorsolateral prefrontal cortex is crucially involved in numerous cognitive and affective processes that are implicated in the phenotypes of both substance use disorders and other neuropsychiatric diseases and has become the principal site to deliver transcranial magnetic stimulation for their treatment. However, the dorsolateral prefrontal cortex is an anatomically large and functionally heterogeneous region, and the specific dorsolateral prefrontal cortex locus and dorsolateral prefrontal cortex-based functional circuits that contribute to drug relapse and/or treatment outcome remain unknown. We systematically investigated the relationship of cocaine relapse with functional circuits from 98 dorsolateral prefrontal cortex regions-of-interest defined by evenly sampling the entire surface of bilateral dorsolateral prefrontal cortex in a cohort of cocaine dependent patients (n = 43, 5 Fr) following a psychosocial treatment intervention. Cox regression models were utilized to predict relapse likelihood based on dorsolateral prefrontal cortex functional connectivity strength. Functional connectivity from only 3 of the 98 dorsolateral prefrontal cortex loci, one in the left and two in the right hemisphere, significantly predicted cocaine relapse with an accuracy of 83.9%, 84.6% and 85.4%, respectively. Combining all three loci significantly improved prediction validity to 87.5%. Protective and risk circuits related to these dorsolateral prefrontal cortex loci were identified that have previously been implicated to support ‘bottom up’ drive to use drug and ‘top down’ control over behaviour together with social emotional, learning and memory processing. Three dorsolateral prefrontal cortex-centric circuits were identified that predict relapse to cocaine use with high accuracy. These functionally distinct dorsolateral prefrontal cortex-based circuits provide insights into the multiple roles played by the dorsolateral prefrontal cortex in cognitive and affective functioning that affects treatment outcome. The identified dorsolateral prefrontal cortex loci may serve as potential neuromodulation targets to be tested in subsequent clinical studies for addiction treatment and as clinically relevant biomarkers of its efficacy. Zhai et al. identify three dorsolateral prefrontal cortex (dlPFC)-centric circuits that predict cocaine relapse with high accuracy, providing insights into the multiple roles of the dlPFC in brain functioning that affects treatment outcome and suggesting the dlPFC loci as potential neuromodulation targets for addiction treatment., Graphical Abstract Graphical Abstract

Background Recent studies advocate a connectivity pattern wider than previously believed of the uncinate fasciculus that extends to the ventrolateral and dorsolateral prefrontal cortices. These new percepts on the connectivity of the tract suggest a more expansive role for the uncinate fasciculus. Our aim was to shed light on this controversy through fiber dissections. Methods Twenty normal adult human formalin-fixed cerebral hemispheres were used. Focused dissections on the insular, orbitofrontal, ventromedial, ventrolateral, and dorsolateral prefrontal areas were performed to record the topography of the frontal terminations of the uncinate fasciculus. Results Three discrete fiber layers were consistently disclosed: the first layer was recorded to terminate at the posterior orbital gyrus and pars orbitalis, the second layer at the posterior two thirds of the gyrus rectus, and the last layer at the posterior one third of the paraolfactory gyrus. The insular apex was documented as a crucial landmark regarding the topographic differentiation of the uncinate and occipitofrontal fasciculi (i.e., fibers that travel ventrally belong to the uncinate fasciculus whereas those traveling dorsally are occipitofrontal fibers). Conclusions The frontal terminations of the uncinate fasciculus were consistently documented to project to the posterior orbitofrontal area. The area of the insular apex is introduced for the first time as a crucial surface landmark to effectively distinguish the stems of the uncinate and occipitofrontal fasciculi. This finding could refine the spatial resolution of awake subcortical mapping, especially for insular lesions, and improve the accuracy of in vivo diffusion tensor imaging protocols.

The present brief review for this Special Issue summarizes some of the original research on the emotional modulation of memory. The review begins by highlighting the pioneering research from James L. McGaugh and colleagues demonstrating modulatory effects of post-training drug administration on memory consolidation, in particular the stress hormone epinephrine. The subsequent discovery of a critical role for the basolateral amygdala in emotional modulation of memory is described. Within the context of a multiple systems approach to memory focusing on selective roles for the hippocampus and dorsolateral striatum in cognitive and habit memory, the original studies indicating that robust emotional arousal can bias animals and humans toward the predominant use of habit memory are reviewed. This effect of emotional arousal on the relative use of multiple memory systems depends on a modulatory role of the basolateral amygdala. Finally, we briefly consider how an emotion-induced enhancement of dorsolateral striatal-dependent memory may be relevant to understanding maladaptive habitual behaviors in certain human psychopathologies.

The shift in control from dorsomedial to dorsolateral striatum during skill and habit formation has been well established, but whether striatal subregions orchestrate this shift co-operatively or competitively remains unclear. Cortical inputs have also been implicated in the shift towards automaticity, but it is unknown if they mirror their downstream striatal targets across this transition. We addressed these questions using a five-step heterogeneous action sequencing task in rats that is optimally performed by automated chains of actions. By optimising automatic habitual responding, we discovered that loss of function in the dorsomedial striatum accelerated sequence acquisition. In contrast, loss of function in the dorsolateral striatum impeded acquisition of sequencing, demonstrating functional opposition within the striatum. Unexpectedly the medial prefrontal cortex was not involved, however the lateral orbitofrontal cortex was critical. These results shift current theories about striatal control of behavior to a model of competitive opposition, where the dorsomedial striatum acts in a gating role to inhibit dorsolateral-striatum driven behavior.

Observation of others’ painful heat stimulation involves spinal cord responses that are distinct from sensory processing., Observing others’ aversive experiences is central to know what is dangerous for ourselves. Hence, observation often elicits behavioral and physiological responses comparable to first-hand aversive experiences and engages overlapping brain activation. While brain activation to first-hand aversive experiences relies on connections to the spinal cord, it is unresolved whether merely observing aversive stimulation also involves responses in the spinal cord. Here, we show that observation of others receiving painful heat stimulation involves neural responses in the spinal cord, located in the same cervical segment as first-hand heat pain. However, while first-hand painful experiences are coded within dorsolateral regions of the spinal cord, observation of others’ painful heat stimulation involves medial regions. Dorsolateral areas that process first-hand pain exhibit negative responses when observing pain in others. Our results suggest a distinct processing between self and others’ pain in the spinal cord when integrating social information.

Distributed training has long been known to lead to more robust memory formation as compared to massed training. Here we demonstrate that distributed and massed training differentially engage the dorsolateral and dorsomedial striatum and optogenetic priming of dorsolateral striatum can artificially increase the robustness of massed training to the level of distributed training, identifying a novel therapeutic avenue for memory enhancement.

Introduction This study aimed to evaluate the clinical outcomes of 16 patients with capitellum and trochlea fractures that were treated using isolated headless compression screws or a combination of dorsolateral locking plates and anterior-to-posterior screws. We also investigated the presence of lateral epicondyle fragments because this fragment is especially important when making decisions regarding the surgical approach and implants. Materials and methods We conducted a retrospective analysis of 16 patients with capitellum and trochlea fractures. Clinical, radiographic (based on CT scans), and elbow-specific outcomes, including the Mayo Elbow Performance Index (MEPI), were evaluated at a mean of 23.5 months postoperatively. Results The average MEPI scores in patients with Dubberley type A (non-posterior comminution) and type B (posterior comminution) fractures were 88 and 78, respectively (p=0.08). Headless compression screws were used in 10 cases of type A fracture and one case of type B fracture. A combination of dorsolateral locking plates and anterior-to-posterior screws was used in five cases of type B fracture. Hardware loosening was seen in one case of type B fracture with isolated screw fixation. The presence of a lateral epicondyle fragment was significantly associated with the type B group (6/6 patients; 100%). In contrast, patients in the type A group rarely had posterior comminution of the lateral epicondyle fragment (2/10 patients; 20%). Conclusions Capitellum and trochlea fractures with posterior comminution, which typically presented with lateral epicondylar fragments, were safely and effectively treated with a combination of dorsolateral locking plates and anterior-to-posterior screws through lateral approaches. Cases without posterior comminution were treated with headless compression screws with no complications. The Dubberley classification system provides helpful information to determine the fixation strategy.

Background Dorsolateral medullary infarction is a typical cerebral infarction which is characterized by Wallenberg’s syndrome. Neurotrophic keratopathy is an uncommon consequence of dorsolateral medullary infarction. At present, the protocol is aimed to study the dynamic changes in corneal innervation and the ocular surface environment after dorsolateral medullary infarction. Methods This study will involve consecutive data from all medical records of patients within 7 days of acute dorsolateral medullary infarction onset at the Departments of Neurology from 10 collaborating stroke centers. Eligible patients will mainly be characterized based on detailed physical examinations, multimodal imaging, and corneal related examinations and patients will be followed-up for 2 years. Neurotrophic keratopathy after dorsolateral medullary infarction is the primary endpoint. The dynamic histological corneal innervation and ocular surface environment after dorsolateral medullary infarction will be observed during the follow-up period. Discussion This multicentric, prospective registry is the first to identify and characterize the dynamic changes of corneal innervation and the ocular surface environment after acute dorsolateral medullary infarction. The significance of the study is to emphasize that the curative effect is based on the doctors’ identification of the disease in the earliest stage before irreversible damage occurs to the cornea. Trial registration The registry was registered (ChiCTR-OPC-17,011,625) on June 11, 2017.

The present study had three main aims: (1) to explore the possible relationships between the two dimensions of negative symptoms (NS) with the three frontal behavioral syndromes (dorsolateral, orbitofrontal and the anterior or mesial cingulate circuit) in patients with schizophrenia, (2) to determine the influence of sociodemographic and clinical variables on the severity of the two dimensions of NS (expressive deficits and disordered relationships/avolition), and (3) to explore the possible relationships between the two dimensions of NS and social functioning. We evaluated a group of 33 patients with schizophrenia with a predominance of NS using the self-reported version of the Frontal System Behavior scale. To quantify the severity of NS, the Assessment of Negative Symptoms (SANS) scale was used. The results revealed that the two dimensions of NS correlate positively with the behavioral syndrome of dorsolateral prefrontal origin. Regarding the influence of sociodemographic and clinical variables, in patients with a long evolution the NS of the expressive deficits dimension were less severe than in patients with a short evolution. A negative correlation was found between the severity of NS of the disordered relationships/avolition dimension and perceived social functioning. Our results show the importance of differentiating between the two dimensions of NS to characterize better their possible frontal etiology and impact on clinical course and social functioning.

Behavior and cognition in humans and other primates rely on networks of brain areas guided by the frontal cortex. The marmoset offers exciting new opportunities to study links between brain physiology and behavior, but the functions of frontal cortex areas are still being identified in this species. Here, we provide the first evidence of visual receptive fields in the marmoset dorsolateral frontal cortex, an important step toward future studies of visual cognitive behavior.

Highlights • Despite their major effects on positive symptoms, antipsychotics do not have a significant effect on cognition in schizophrenia • Bilateral high frequency rTMS targeting dorsolateral prefrontal cortices has been effective on working memory • Bilateral 20 Hz rTMS improved attention and verbal working memory in schizophrenia patients, • It also improved the competence of switching the perceptional set up under a disruptive effect towards new instructions, in this study

Age-related differences in dorsolateral prefrontal cortex (DLPFC) structure and function have each been linked to working memory. However, few studies have integrated multimodal imaging to simultaneously investigate relationships among structure, function, and cognition. We aimed to clarify how specifically DLPFC structure and function contribute to working memory in healthy older adults. In total, 138 participants aged 65–88 underwent 3 T neuroimaging and were divided into higher and lower groups based on a median split of in-scanner n-back task performance. Three a priori spherical DLPFC regions of interest (ROIs) were used to quantify blood-oxygen-level-dependent (BOLD) signal and FreeSurfer-derived surface area, cortical thickness, and white matter volume. Binary logistic regressions adjusting for age, sex, education, and scanner type revealed that greater left and right DLPFC BOLD signal predicted the probability of higher performing group membership (P values.05). Importantly, this suggests BOLD signal and surface area may independently contribute to working memory performance in healthy older adults.

The prefrontal cortex (PFC) supports decision-making, goal tracking, and planning. Spatial navigation is a behavior that taxes these cognitive processes, yet the role of the PFC in models of navigation has been largely overlooked. In humans, activity in dorsolateral PFC (dlPFC) and ventrolateral PFC (vlPFC) during detours, reveal a role in inhibition and replanning. Dorsal anterior cingulate cortex (dACC) is implicated in planning and spontaneous internally-generated changes of route. Orbitofrontal cortex (OFC) integrates representations of the environment with the value of actions, providing a 'map' of possible decisions. In rodents, medial frontal areas interact with hippocampus during spatial decisions and switching between navigation strategies. In reviewing these advances, we provide a framework for how different prefrontal regions may contribute to different stages of navigation.

BACKGROUND: Semantic variant primary progressive aphasia (svPPA), a clinical syndrome characterized by loss of semantic knowledge, is associated with neurodegeneration that starts in the anterior temporal lobe (ATL) and gradually spreads towards posterior temporal and medial frontal areas. At the earliest stages, atrophy may be predominantly lateralized to either the left or right ATL, leading to different clinical profiles with greatest impairment of word comprehension or visual/social semantics, respectively. METHODS & PROCEDURES: We report the in-depth longitudinal investigation of cognitive and neuroanatomical features of JB, an unusual case of ATL neurodegeneration with relative sparing of left lateral ATL regions. OUTCOMES & RESULTS: Over the course of nine years, neurodegeneration progressed to involve bilateral temporo-lateral and frontal regions, resulting in a relatively symmetric and diffuse frontotemporal atrophy pattern. In parallel, JB developed greater behavioral, cognitive, and language impairments, as well as signs of motor neuron disease at her last evaluation. Episodic memory and socio-emotional processing deficits arose, likely secondary to semantic verbal deficits, while visuospatial processing, executive function, and non-semantic language abilities remained largely unaffected throughout the course of the disease. CONCLUSIONS: The details of this rare case of early medial more than lateral ATL degeneration are consistent with a bilateral organization of the semantic system and, crucially, with a functional dissociation between medial paralimbic and lateral neocortical temporal regions. Cases of frontotemporal dementia (FTD) such as JB, who initially do not meet current clinical criteria for svPPA and instead present with some features of behavioral variant FTD, highlight the need for specific criteria for the right temporal variant of FTD that we propose could be called semantic variant FTD.

A few studies have identified the structural connection between the premotor area and the lateral prefrontal cortex (DLPFC) as the frontal longitudinal system (FLS). This study investigated the existence of a direct segment (none U-fibre) of the superior part of the FLS (sFLS), which connects the dorsal premotor cortex (PMd) and DLPFC and analysed its asymmetry and termination point patterns. A dataset of diffusion-weighted images from 48 subjects was used for generalised q-sampling imaging tractography. Additionally, a white-fibre dissection was conducted in two right hemispheres. An analysis of spatial location, termination points, laterality, and correlation with the subjects’ gender or handedness was performed. The sFLS was found to have a deeper longitudinal bundle directly connecting the PMd and DLPFC. The bundle is referred to hereafter as the superior frontal longitudinal tract (SFLT). The SFLT was reconstructed in 100% of right and 88% of left hemispheres. It exhibited variable patterns in different subjects in their posterior terminations. In addition, it was found to possess a complicated spatial relationship with the adjacent bundles. The SFLT was revealed successfully in two cadaveric right hemispheres, where the posterior terminations were found to originate in the PMd independent of the superior longitudinal fasciculus.

Chronic cigarette smoking is associated with regional metabolite abnormalities in choline-containing compounds, creatine-containing compounds, glutamate, and N-acetylaspartate. The effects of cigarette smoking on anterior frontal cortical gamma-aminobutyric acid (GABA) concentration is unknown. This study compared chronic smokers (n=33) and non-smokers (n=31) on anterior cingulate cortex (ACC) and right dorsolateral prefrontal cortex (DLPFC) GABA+ (the sum of GABA and co-edited macromolecules) concentrations and associations of GABA+ levels in these regions with neurocognition in seven different domains of functioning, decision-making and impulsivity measures. Smokers had significantly lower right DLPFC GABA+ concentration than non-smokers, but groups were equivalent on ACC GABA+ level. Across groups, greater number of days since end of menstrual cycle were related to higher GABA+ level in the ACC, but not right DLPFC GABA+ concentration. In exploratory correlation analyses, higher ACC and right DLPFC GABA+ levels were associated with faster processing speed and better auditory-verbal memory, respectively in the combined group of smokers and non-smokers; in smokers only, higher ACC GABA+ was related to better decision-making and auditory-verbal learning. This study contributes additional novel data on the adverse effects of chronic cigarette smoking on the adult human brain and demonstrated ACC and DLPFC GABA+ concentrations were associated with neurocognition and decision-making/impulsivity in active cigarette smokers. Longitudinal studies on the effects of smoking cessation on regional brain GABA levels, with a greater number of female participants, are required to determine if the observed metabolite abnormalities are persistent or normalize with smoking cessation.

Resumen Objetivo: Evaluar clínicamente a pacientes con lesiones distales combinadas del pulgar tratados mediante colgajo dorsolateral o colgajo en isla mediopalmar radial. Materiales y Métodos: Se comparó retrospectivamente a 20 pacientes (14 hombres y 6 mujeres; promedio de edad 35 años) con lesiones traumáticas combinadas distales del pulgar, operados por dos cirujanos, con técnicas diferentes. Los pacientes no tenían antecedentes quirúrgicos y el seguimiento mínimo fue de 24 meses. Se evaluaron el resultado subjetivo usando el índice de satisfacción, la escala analógica visual para dolor y el puntaje QuickDASH, y el resultado objetivo mediante el test de discriminación de 2 puntos, el tiempo quirúrgico promedio y la necesidad de reeducación espacial digital. Resultados: La media desde el ingreso hasta el alta laboral fue de 7 semanas (rango 6-8). Resultados promedio posoperatorios: escala analógica visual 01/10, ambos grupos. Grupo con colgajo dorsolateral: índice de satisfacción 97%, test de discrimi-nación de 2 puntos 4 mm, puntaje QuickDASH 2,5; tiempo quirúrgico 45 min, sin necesidad de reeducación espacial digital. Grupo con colgajo en isla mediopalmar radial: índice de satisfacción 92%, test de discriminación de 2 puntos 6 mm, puntaje QuickDASH 8, tiempo quirúrgico 60 min; 4 pacientes requirieron reeducación espacial digital. Conclusión: Los colgajos dorsolateral y en isla mediopalmar radial resultaron eficaces en el tratamiento de lesiones traumáticas distales del pulgar, aunque el colgajo dorsolateral tuvo mejores puntajes de evaluación objetiva y requirió menos tiempo quirúrgico. Abstract Objective: To clinically evaluate patients with combined distal thumb lesions treated by a dorsolateral flap or radial midpalmar island flap. Materials and Methods: We retrospectively compared 20 patients (14 males and 6 females, averaging 35 years) with combined distal thumb traumatic lesions, who were operated on by two surgeons using different techniques. Patients had no pre-vious surgical history and a minimum follow-up period of 24 months. Subjective outcome was evaluated by satisfaction index (SI), visual analogue scale (VAS), and QuickDASH score. Objective outcome was evaluated by two-point discrimination test (TPDT), average surgical time (ST), and need for digital spatial reeducation (DSR). Results: Time from admission to medical discharge averaged 7 weeks (range, 6-8). Average postoperative results: VAS for pain, 01/10 (both groups); IS, 97% vs. 92% (dorsolateral flap group vs. radial midpalmar island flap); TPDT, 4 mm vs. 6 mm; QuickDASH, 2.5 vs. 8; ST, 45 minutes vs. 60 minutes; need for DSR, 0 vs. 4 cases. Conclusion: Both the dorsolateral flap and the radial midpalmar island flap techniques were effective in the treatment of distal thumb traumatic lesions, although the dorsolateral flap achieved better objective evaluation scores and required less ST.

Rostro-caudal specificity of corticospinal tract (CST) projections from different areas of the cortex was assessed by retrograde labeling with fluorogold and retrograde transfection following retro-AAV/Cre injection into the spinal cord of tdT reporter mice. Injections at C5 led to retrograde labeling of neurons throughout forelimb area of the sensorimotor cortex and a region in the dorsolateral cortex near the barrel field (S2). Injections at L2 led to retrograde labeling of neurons in the posterior sensorimotor cortex (hindlimb area) but not the dorsolateral cortex. With injections of biotinylated dextran amine (BDA) into the main sensorimotor cortex (forelimb region), labeled axons terminated selectively at cervical levels. With BDA injections into caudal sensorimotor cortex (hindlimb region), labeled axons passed through cervical levels without sending collaterals into the gray matter and then elaborated terminal arbors at thoracic sacral levels. With BDA injections into the dorsolateral cortex near the barrel field, labeled axons terminated at high cervical levels. Axons from medial sensorimotor cortex terminated primarily in intermediate laminae and axons from lateral sensorimotor cortex terminated primarily in laminae III–V of the dorsal horn. One of the descending pathways seen in rats (the ventral CST) was not observed in most mice.