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Temporal Areas (temporal + area)
Selected AbstractsDynamic links between theta executive functions and alpha storage buffers in auditory and visual working memoryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2010Masahiro Kawasaki Abstract Working memory (WM) tasks require not only distinct functions such as a storage buffer and central executive functions, but also coordination among these functions. Neuroimaging studies have revealed the contributions of different brain regions to different functional roles in WM tasks; however, little is known about the neural mechanism governing their coordination. Electroencephalographic (EEG) rhythms, especially theta and alpha, are known to appear over distributed brain regions during WM tasks, but the rhythms associated with task-relevant regional coupling have not been obtained thus far. In this study, we conducted time,frequency analyses for EEG data in WM tasks that include manipulation periods and memory storage buffer periods. We used both auditory WM tasks and visual WM tasks. The results successfully demonstrated function-specific EEG activities. The frontal theta amplitudes increased during the manipulation periods of both tasks. The alpha amplitudes increased during not only the manipulation but also the maintenance periods in the temporal area for the auditory WM and the parietal area for the visual WM. The phase synchronization analyses indicated that, under the relevant task conditions, the temporal and parietal regions show enhanced phase synchronization in the theta bands with the frontal region, whereas phase synchronization between theta and alpha is significantly enhanced only within the individual areas. Our results suggest that WM task-relevant brain regions are coordinated by distant theta synchronization for central executive functions, by local alpha synchronization for the memory storage buffer, and by theta,alpha coupling for inter-functional integration. [source] Heteromodal connections supporting multisensory integration at low levels of cortical processing in the monkeyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2005Céline Cappe Abstract While multisensory integration is thought to occur in higher hierarchical cortical areas, recent studies in man and monkey have revealed plurisensory modulations of activity in areas previously thought to be unimodal. To determine the cortical network involved in multisensory interactions, we performed multiple injections of different retrograde tracers in unimodal auditory (core), somatosensory (1/3b) and visual (V2 and MT) cortical areas of the marmoset. We found three types of heteromodal connections linking unimodal sensory areas. Visuo-somatosensory projections were observed originating from visual areas [probably the ventral and dorsal fundus of the superior temporal area (FSTv and FSTd), and middle temporal crescent (MTc)] toward areas 1/3b. Somatosensory projections to the auditory cortex were present from S2 and the anterior bank of the lateral sulcus. Finally, a visuo-auditory projection arises from an area anterior to the superior temporal sulcus (STS) toward the auditory core. Injections in different sensory regions allow us to define the frontal convexity and the temporal opercular caudal cortex as putative polysensory areas. A quantitative analysis of the laminar distribution of projecting neurons showed that heteromodal connections could be either feedback or feedforward. Taken together, our results provide the anatomical pathway for multisensory integration at low levels of information processing in the primate and argue against a strict hierarchical model. [source] Response properties of PMLS and PLLS neurons to simulated optic flow patternsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2000Bing Li Abstract The processing of optic flow information has been extensively investigated in the medial superior temporal area (MST) of the macaque. In the cat, the posteromedial area and the posterolateral area in the lateral suprasylvian cortex (PMLS and PLLS, respectively) have been suggested as likely participants according to their direction preferences to moving objects. In the present study, 203 PMLS and 123 PLLS neurons were tested with simulated optic flow patterns composed of random dots (including expansion and contraction, clockwise and counter-clockwise rotation, and translation) and moving bar stimuli. About 90% of the neurons were found to be excited by the optic flow stimuli and most of them were multiple-responsive to different flow patterns. Only 20,25% of the cells were selective to different optic flow modes, and in general, the direction preference was fairly modest. The selective cells showed stronger directionality to both flow field and moving bar than nonselective cells. However, the optic flow response properties in the PMLS and PLLS were not well correlated with the direction preference to moving bars. In accordance with previous findings, the PMLS was analogous to the middle temporal area of the macaque in many respects. As for the PLLS cells, they were sensitive to fewer types of stimuli, but responded better and more selectively to radial motion. All these results suggest that the two lateral suprasylvian areas are unlikely to be specialized for the analysis or discrimination of different flow patterns, but may play some kind of relay role in optic flow information processing. [source] Dermatomyositis presenting as panniculitisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2000Yen-Yu Chao MD A 44-year-old obese woman was transferred to our clinic with a diagnosis of panniculitis. Examination showed multiple, indurated, erythematous, painful nodules and plaques distributed on the shoulders, back, forechest, abdomen, buttock, and bilateral thighs. These skin lesions appeared 2 months previously, measured 5,8 cm, and were tender on palpation. No obvious inducing factor was traced. The lesions seemed unresponsive to treatment with nonsteroidal anti-inflammatory drugs (ibuprofen, 400 mg three times a day) as similar lesions appeared in subsequent visits. Progressive proximal muscle weakness was found 1 month later. She was then admitted via the emergency room because of extensive painful skin plaques and abdominal pain. Diffuse erythematous to violaceous swelling of the face, neck, and shoulder was noted at about the same time ( Fig. 1). A skin biopsy specimen from the nodular lesion showed poikilomatous epidermal changes ( Fig. 2), and marked mononuclear cell infiltration in the dermis and subcutaneous fat ( Fig. 3). Dermatomyositis was considered as the diffuse violaceous facial erythema could be a form of heliotrope eruption, but Gottron's papule was not found. At admission, serum creatinine phosphokinase (CPK) was mildly elevated (436 IU/L; normal range, 20,170 IU/L), but serum asparagine transaminase (AST) and lactate dehydrogenase (LDH) levels were within normal limits (36 IU/L; normal, 11,47 IU/L; and 108 IU/L; normal, 90,280 IU/L, respectively). Antinuclear antibody was 1 : 80 positive with an atypical speckled pattern. Muscle strength was weakest during the first 2 days, about grade 3 by the Medical Research Council (MRC) of Great Britain scale. Gower's sign was positive. An electromyogram showed myopathic changes and a nerve conduction velocity study was normal. Serum enzymes were elevated further on the third day: AST, 55 IU/L; CPK, 783 IU/L with 100% MM form. The diagnosis of dermatomyositis was established. As for the work-up result, anti-dsDNA antibody, anti-ENA antibody, and anti-Jo1 antibody were negative. Tumor marker screen (,-HCG, AFP, CEA, and CA-125), was negative, and rhinolaryngopharyngoscope examination and gynecologic sonography were normal. Figure 1. Diffuse erythematous swelling with subtle violaceous hue extending from the temporal area to the cheeks, neck, and shoulders. The crusted lip ulcers of herpes simplex were also noted Figure 2. Basketweave hyperkeratosis, mild acanthosis, subtle vacuolar degeneration of the basal cells, and melanin incontinence (hematoxylin and eosin, ×400) Figure 3. Heavy mononuclear cells infiltrated in the subcutaneous fat tissue (hematoxylin and eosin, ×100) Pancreatitis was initially suspected because of epigastric pain and tenderness, elevated serum lipase (382 U/L; normal, 23,200 U/L), and amylase (145 U/L; normal, 35,118 U/L). No evidence of pancreatitis could be found in abdominal sonography and abdominal computed tomography (CT), however. The epigastric pain and tenderness subsided soon after admission and the serum pancreatic enzyme level declined on the second day (amylase 69 U/L; lipase, 276 U/L). The patient was then diagnosed with dermatomyositis and treated with prednisolone (120 mg/day). CPK dropped dramatically from 3286 IU/L the day before treatment to 1197 IU/L 3 days after. Panniculitis lessened and the muscle power improved after 1 week of treatment. The disease activity fluctuated even with treatment with prednisolone and the patient often felt listless and weak. The muscle weakness sometimes deteriorated to affect the patient's mobility. Facial erythema and panniculitis-like lesions were found during the worse times. Methotrexate and azathioprine were then added (7.5 mg and 250 mg per week, respectively), but CPK was still mildly elevated (189 IU/L), and the patient still felt ill. Human immune globulin (5%, 500 mL per day, 5 days per month) intravenous infusion was initiated thereafter. There was a dramatic response. Full muscle strength was retained and CPK was within the normal range in the following 6 months with only immune globulin therapy. [source] Specificity of regional brain activity in anxiety types during emotion processingPSYCHOPHYSIOLOGY, Issue 3 2007Anna S. Engels Abstract The present study tested the hypothesis that anxious apprehension involves more left- than right-hemisphere activity and that anxious arousal is associated with the opposite pattern. Behavioral and fMRI responses to threat stimuli in an emotional Stroop task were examined in nonpatient groups reporting anxious apprehension, anxious arousal, or neither. Reaction times were longer for negative than for neutral words. As predicted, brain activation distinguished anxious groups in a left inferior frontal region associated with speech production and in a right-hemisphere inferior temporal area. Addressing a second hypothesis about left-frontal involvement in emotion, distinct left frontal regions were associated with anxious apprehension versus processing of positive information. Results support the proposed distinction between the two types of anxiety and resolve an inconsistency about the role of left-frontal activation in emotion and psychopathology. [source] No effects of mobile phone use on cortical auditory change-detection in children: An ERP studyBIOELECTROMAGNETICS, Issue 3 2010Myoung Soo Kwon Abstract We investigated the effect of mobile phone use on the auditory sensory memory in children. Auditory event-related potentials (ERPs), P1, N2, mismatch negativity (MMN), and P3a, were recorded from 17 children, aged 11,12 years, in the recently developed multi-feature paradigm. This paradigm allows one to determine the neural change-detection profile consisting of several different types of acoustic changes. During the recording, an ordinary GSM (Global System for Mobile Communications) mobile phone emitting 902,MHz (pulsed at 217,Hz) electromagnetic field (EMF) was placed on the ear, over the left or right temporal area (SAR1g,=,1.14,W/kg, SAR10g,=,0.82,W/kg, peak value,=,1.21,W/kg). The EMF was either on or off in a single-blind manner. We found that a short exposure (two 6,min blocks for each side) to mobile phone EMF has no statistically significant effects on the neural change-detection profile measured with the MMN. Furthermore, the multi-feature paradigm was shown to be well suited for studies of perception accuracy and sensory memory in children. However, it should be noted that the present study only had sufficient statistical power to detect a large effect size. Bioelectromagnetics 31:191,199, 2010. © 2009 Wiley-Liss, Inc. [source] Noninvasive Lower Eyelid Blepharoplasty: A New Technique Using Nonablative Radiofrequency on Periorbital SkinDERMATOLOGIC SURGERY, Issue 2 2004Javier Ruiz-esparza MDArticle first published online: 3 FEB 200 Background. Laxity and rhytids of the lower eyelids are common cosmetic concerns. Historically, correction has either been surgical through either transcutaneous or transconjunctival blepharoplasty or ablative through laser resurfacing or chemical peeling. Therapeutic options usually require significant postoperative healing and have the potential risk of scarring ectropion or pigmentary loss. Objective. To report the use of a new technique that uses nonablative radiofrequency (NARF) to tighten noninvasively and nonsurgically the flaccid skin of the lower eyelids by treating the periorbital area to produce cosmetic improvement. Methods. Nine patients with skin flaccidity of the lower eyelids had a single treatment session with NARF in a small area of skin in the periorbital region, specifically the zygomatic and/or temporal areas. All patients were treated with topical anesthesia only. The treatment lasted approximately 10 minutes. No postoperative care was required. Results. All of the nine patients in the study achieved cosmetic improvement of the eyelids ostensibly through skin contraction. All patients were able to return to their normal routines immediately. Although the results were gradual, patient satisfaction was remarkable. No complications were seen in this study. Conclusion. This new procedure using NARF was successful in providing a safe, noninvasive, cosmetic improvement in these patients with excessive skin laxity of the lower eyelids. Postoperative morbidity, including down time and complications, was not seen. [source] Language-Related Potentials in Temporal Lobe Epilepsy Before and After Surgical TreatmentEPILEPSIA, Issue 2000Toshihiko Ito Purpose: Temporal lobectomy has contributed to treatment for medically intractable epilepsies. However, influence of the surgical treatment on cognitive function is not still clear, especially from the electrophysiological viewpoint. N400, an event related potential (ERP) named for its negative polarity and peak latency of 400 ms, is reported to be an electrophysiological sign of neural activities associated with semantic priming in language perception. In the present study, ERPs are applied to evaluate the cognitive function of temporal lobe epilepsy before and after temporal lobectomy. Methods: Two patients with intractable temporal lobe epilepsy participated in this study. Fifteen normal subjects served as controls. The incongruous sentence task (Kutas and Hillyard 1980) was used to record N400 components in an auditory modality. Two types of sentences (40 Japanese sentences for each type) were prepared, in which the terminal words were either semantically congruent or incongruent. The scntences were randomly presented at approximately 65 dB SPL peak intensity. ERPs were recorded according to the international 10,20 system, with a balanced non-cephalic electrode reference and 2 1 channels. The band-pass filter was set from 0.5 to 30 Hz, and the ERPs were sampled at 500 Hz from 200 ms before the onset of terminal words to 824 ms post-stimulus. Waves were calculated by subtracting ERPs in the congruent condition from those in the incongruent condition. N400 was scored as the most negative point between 250 and 450 ms in the subtraction waves. Amplitudes were measured from the baseline of 100 ms before the terminal words. Motor responses were also measured with a right index finger, to estimate the accuracy of understanding sentences. Results: Case I was a 22-year-old male who had intractable epilepsy for 7 years. Magnetic resonance imaging (MRI) showed high-intensity signals in the right amygdalo-hippocampal region. The epileptic seizures were confirmed to originate from the region hy electroencephalography/closed-circuit television monitoring, and single-photon-emission computed tomography. ERPs were recorded I month before and after the right anterior temporal lobectomy. Before the surgery, the rate of correct responses showed no difference between the patient (96 %) and the controls (96 %). The amplitudes of N400 for the patient reduced in the right frontal and central areas (F4, C4), comparing to 99 % confidence limit for control subjects. After the surgery, the rate of correct responses was 97 %, and the amplitudes reduced in the right central, parietal, and posterior temporal areas (C4, P4, 0 2, T6). Case 2 (37-year-old female) had intractable epilepsy for 30 years. MRI showed brain atrophy in the right hippocampal region. The epileptic seizures were confirmed to originate from the region. N400 was recorded 3 months after the resection. The rate of correct responses was 95 %. The amplitudes of N400 were lower in the right frontal, parietal, and temporal areas (electrodes Fp2, F4, P4, T6, Pz), comparing to 99 % confidence limit of controls. Conclusions: Before the lpbectomy, the reduction of amplitudes of N400 indicated that the pathogenesis of intractable temporal lobe epilepsy would influence the process of semantic priming in language perception. After the resection, it was suggested that the right temporal lobectomy might affect the cognitive function in the brain from electrophysiological aspects. We could benefit from further study including analysis of the discrepancy between the amplitudes of N400 and behavioral responses. [source] 99mTc-ethyl cysteinate dimer brain SPECT findings in early stage of dementia with Lewy bodies and Parkinson's disease patients: a correlation with neuropsychological testsEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2008C.-C. Chang We examined clinical presentations, neuropsychological findings, and perfusion patterns of 99mTc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) in patients with early stage dementia with Lewy bodies (DLB) (n = 17) and Parkinson's disease (PD) (n = 16), with age-matched healthy controls (n = 10). Seven paired regions of interest (ROIs) were drawn manually including inferior frontal, temporal, parietal, occipital, parieto-occipital junction, striatum and thalamus for semiquantitative measurement. Neuropsychological tests were applied for clinical correlation. The SPECT results showed significant hypoperfusion in DLB group in frontal, parietal, thalamus, temporal ROIs compared with controls (P < 0.01) whilst signals in temporal areas was significantly reduced compared with PD group (P < 0.05). Neuropsychological tests showed that DLB patients had deficits in mental manipulation, short-term memory, abstract thinking, drawing and semantic verbal fluencies (P < 0.05, compared with control). In addition, DLB group had lower scores than those with PD in mental manipulation, drawing and semantic verbal fluency (P < 0.05). Our study showed that even in early stages of DLB, neuropsychological and perfusion patterns were evident and may be different from PD group, despite they shared certain similarities both in neuropsychological and image findings compared with age-matched controls. [source] Heritability of regional and global brain structure at the onset of puberty: A magnetic resonance imaging study in 9-year-old twin pairsHUMAN BRAIN MAPPING, Issue 7 2009Jiska S. Peper Abstract Puberty represents the phase of sexual maturity, signaling the change from childhood into adulthood. During childhood and adolescence, prominent changes take place in the brain. Recently, variation in frontal, temporal, and parietal areas was found to be under varying genetic control between 5 and 19 years of age. However, at the onset of puberty, the extent to which variation in brain structures is influenced by genetic factors (heritability) is not known. Moreover, whether a direct link between human pubertal development and brain structure exists has not been studied. Here, we studied the heritability of brain structures at 9 years of age in 107 monozygotic and dizygotic twin pairs (N = 210 individuals) using volumetric MRI and voxel-based morphometry. Children showing the first signs of secondary sexual characteristics (N = 47 individuals) were compared with children without these signs, based on Tanner-stages. High heritabilities of intracranial, total brain, cerebellum, and gray and white matter volumes (up to 91%) were found. Regionally, the posterior fronto-occipital, corpus callosum, and superior longitudinal fascicles (up to 93%), and the amygdala, superior frontal and middle temporal cortices (up to 83%) were significantly heritable. The onset of secondary sexual characteristics of puberty was associated with decreased frontal and parietal gray matter densities. Thus, in 9-year-old children, global brain volumes, white matter density in fronto-occipital and superior longitudinal fascicles, and gray matter density of (pre-)frontal and temporal areas are highly heritable. Pubertal development may be directly involved in the decreases in gray matter areas that accompany the transition of our brains from childhood into adulthood. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] Diffusion Tensor and Functional Magnetic Resonance Imaging of Diffuse Axonal Injury and Resulting Language ImpairmentJOURNAL OF NEUROIMAGING, Issue 4 2007Hui Mao PhD ABSTRACT Diffuse axonal injury (DAI) is a common aftermath of brain trauma. The diagnosis of DAI is often difficult using conventional magnetic resonance imaging (MRI). We report a diffusion tensor imaging (DTI) study of a patient who sustained DAI presenting with language impairment. Fractional anisotropy (FA) and DTI tractography revealed a reduction of white matter integrity in the left frontal and medial temporal areas. White matter damage identified by DTI was correlated with the patient's language impairment as assessed by functional MRI (fMRI) and a neuropsychological exam. The findings demonstrate the utility of DTI for identifying white matter changes secondary to traumatic brain injury (TBI). [source] Retronasal and Orthonasal Olfactory Function in Relation to Olfactory Bulb Volume in Patients With Posttraumatic Loss of SmellTHE LARYNGOSCOPE, Issue 6 2006Philippe Rombaux MD Abstract Objective: The aims of this study were to evaluate olfactory function with orthonasal and retronasal testing in patients with posttraumatic olfactory loss and to investigate the relation between residual olfactory function and olfactory bulb (OB) volume. Method: A retrospective study of 25 patients with posttraumatic olfactory loss was performed. Orthonasal olfactory function was assessed with the Sniffin' Sticks test kit; retronasal olfactory function was assessed with intraorally applied odors. Magnetic resonance imaging was used to determine OB volume and cortical damage in the frontal and temporal areas. Results: The main outcomes of the present study were the demonstration of a correlation between olfactory function and OB volume, which was more pronounced for retronasal than for orthonasal olfactory function; retronasal olfactory function was most affected in the patients with the most extensive cerebral damage and was least compromised in patients without such damage; OB volumes were smaller in patients with parosmia compared with those without; and the presence of parosmia was clearly associated with the presence of cerebral damage. Conclusion: The data confirm that OB volume is an indicator of olfactory function but, interestingly, in this study, it is largely determined by retronasal olfactory sensitivity. In addition, these results emphasize the role of higher cortical centers in olfactory function, and especially in parosmia, which may, at least in some cases, be related to lesions in the fronto-orbital and anterior temporal cortices. It would be of interest to investigate OB volume further in relation to the prognosis of the disorder. [source] 4331: Anterior segment optical coherence tomography (AS-OCT): a novel diagnostic instrument for conjunctivochalasisACTA OPHTHALMOLOGICA, Issue 2010K GUMUS Purpose To evaluate cross-sectional conjunctivochalasis area (CChA) and tear meniscus area (TMA) using Fourier-Domain-RTVue-100 optical coherence tomography (OCT) before and after conjunctival cauterization and to evaluate inter- and intraobserver reliability. Methods A total of twelve eyes of 7 patients with conjunctivochalasis aged 56 to 87 were evaluated. After topical anesthesia, conjunctival cauterization was performed on the inferior bulbar conjunctiva. All patients underwent anterior segment OCT (AS-OCT) imaging prior to and 4 weeks after the procedure. Cross-sectional TMA and CChA at 3 locations (nasal, center and temporal areas) were measured in all patients. Results Non-significant increases (p= 0.177) in TMA as a whole (3 locations combined) were observed at following cauterization. CChA measurements significantly decreased in all 3 locations after cauterization (p< 0.001). Mean CChA decreased from 0.247 ± 0.24 mm2 to 0.054 ± 0.79 mm2. For two measurements of TMA by examiner 1, intraclass correlation coefficients (ICC) ranged from 0.998 to 0.999. Among two examiners, Cronbach's alpha reliability coefficients were as high as 0.993 and 0.997 before and after conjunctival cauterization. Regarding the CChA measurements, ICC values were similar to those of TMA, but Cronbach's alpha reliability coefficients were slightly less. Conclusion This study indicates the AS-OCT is a useful and reproducible instrument to measure cross-sectional area of conjunctiva prolapsing into the tear meniscus of patients with conjunctivochalasis. The method can monitor effectiveness of thermo reduction of conjunctivochalasis. [source] | |||||||||||||||||||||||||