Temporal Pole (temporal + pole)

Distribution by Scientific Domains


Selected Abstracts


Regional cerebral brain metabolism correlates of neuroticism and extraversion

DEPRESSION AND ANXIETY, Issue 3 2006
Thilo Deckersbach Ph.D.
Abstract Factor-analytic approaches to human personality have consistently identified several core personality traits, such as Extraversion/Introversion, Neuroticism, Agreeableness, Consciousness, and Openness. There is an increasing recognition that certain personality traits may render individuals vulnerable to psychiatric disorders, including anxiety disorders and depression. Our purpose in this study was to explore correlates between the personality dimensions neuroticism and extraversion as assessed by the NEO Five-Factor Inventory (NEO-FFI) and resting regional cerebral glucose metabolism (rCMRglu) in healthy control subjects. Based on the anxiety and depression literatures, we predicted correlations with a network of brain structures, including ventral and medial prefrontal cortex (encompassing anterior cingulate cortex and orbitofrontal cortex), insular cortex, anterior temporal pole, ventral striatum, and the amygdala. Twenty healthy women completed an 18FFDG (18F-fluorodeoxyglucose) positron emission tomography (PET) scan at rest and the NEO-FFI inventory. We investigated correlations between scores on NEO-FFI Neuroticism and Extraversion and rCMRglu using statistical parametric mapping (SPM99). Within a priori search territories, we found significant negative correlations between Neuroticism and rCMRglu in the insular cortex and positive correlations between Extraversion and rCMRglu in the orbitofrontal cortex. No significant correlations were found involving anterior cingulate, amygdala, or ventral striatum. Neuroticism and Extraversion are associated with activity in insular cortex and orbitofrontal cortex, respectively. Depression and Anxiety 23:133,138, 2006. © 2006 Wiley-Liss, Inc. [source]


Regional gray matter reduction and theory of mind deficit in the early phase of schizophrenia: a voxel-based morphometric study

ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2009
R. Herold
Objective:, We tested the association between theory of mind (ToM) performance and structural changes in the brains of patients in the early course of schizophrenia. Method:, Voxel-based morphometry (VBM) data of 18 patients with schizophrenia were compared with those of 21 controls. ToM skills were assessed by computerized faux pas (FP) tasks. Results:, Patients with schizophrenia performed significantly worse in FP tasks than healthy subjects. VBM revealed significantly reduced gray matter density in certain frontal, temporal and subcortical regions in patients with schizophrenia. Poor FP performance of schizophrenics correlated with gray matter reduction in the left orbitofrontal cortex and right temporal pole. Conclusion:, Our data indicate an association between poor ToM performance and regional gray matter reduction in the left orbitofrontal cortex and right temporal pole shortly after the onset of schizophrenia. [source]


Distributed source modeling of language with magnetoencephalography: Application to patients with intractable epilepsy

EPILEPSIA, Issue 10 2009
Carrie R. McDonald
Summary Purpose:, To examine distributed patterns of language processing in healthy controls and patients with epilepsy using magnetoencephalography (MEG), and to evaluate the concordance between laterality of distributed MEG sources and language laterality as determined by the intracarotid amobarbital procedure (IAP). Methods:, MEG was performed in 10 healthy controls using an anatomically constrained, noise-normalized distributed source solution (dynamic statistical parametric map, dSPM). Distributed source modeling of language was then applied to eight patients with intractable epilepsy. Average source strengths within temporoparietal and frontal lobe regions of interest (ROIs) were calculated, and the laterality of activity within ROIs during discrete time windows was compared to results from the IAP. Results:, In healthy controls, dSPM revealed activity in visual cortex bilaterally from ,80 to 120 ms in response to novel words and sensory control stimuli (i.e., false fonts). Activity then spread to fusiform cortex ,160,200 ms, and was dominated by left hemisphere activity in response to novel words. From ,240 to 450 ms, novel words produced activity that was left-lateralized in frontal and temporal lobe regions, including anterior and inferior temporal, temporal pole, and pars opercularis, as well as bilaterally in posterior superior temporal cortex. Analysis of patient data with dSPM demonstrated that from 350 to 450 ms, laterality of temporoparietal sources agreed with the IAP 75% of the time, whereas laterality of frontal MEG sources agreed with the IAP in all eight patients. Discussion:, Our results reveal that dSPM can unveil the timing and spatial extent of language processes in patients with epilepsy and may enhance knowledge of language lateralization and localization for use in preoperative planning. [source]


Differential effects of temporal pole resection with amygdalohippocampectomy versus selective amygdalohippocampectomy on material-specific memory in patients with mesial temporal lobe epilepsy

EPILEPSIA, Issue 1 2008
Christoph Helmstaedter
Summary Purpose: In the surgical treatment of mesial temporal lobe epilepsy, there is converging evidence that individually tailored or selective approaches have a favorable cognitive outcome compared to standard resections. There is, however, also evidence that due to collateral damage, selective surgery can be less selective than suggested. As part of a prospective transregional research project the present study evaluated the outcome in memory and nonmemory functions, following two selective approaches: a combined temporal pole resection with amygdalohippocampectomy (TPR+) and transsylvian selective amygdalohippocampectomy (SAH). Methods: One year after surgery, cognitive outcomes of postoperatively seizure-free patients with mesial TLE and hippocampal sclerosis, who underwent either TPR+ (N = 35) or SAH (N = 62) in two German epilepsy centers (Bonn/Berlin), were compared. Results: Repeated measurement MANOVA and separate post hoc testing indicated a double dissociation of verbal/figural memory outcome as dependent on side and type of surgery. Verbal memory outcome was worse after left-sided operation, but especially for SAH, whereas figural memory outcome was worse after right-sided operation, preferentially for TPR+. Attention improved independent of side or type of surgery, and language functions showed some improvement after right-sided surgeries. Discussion: The results indicate a differential effect of left/right SAH versus TPR+ on material-specific memory insofar as transsylvian SAH appears to be favorable in right and TPR+ in left MTLE. The different outcomes are discussed in terms of a different surgical affection of the temporal pole and stem, and different roles of these structures for verbal and figural memory. [source]


Self-motion and the origin of differential spatial scaling along the septo-temporal axis of the hippocampus

HIPPOCAMPUS, Issue 7 2005
Andrew P. Maurer
Abstract Spatial scaling of place specific activity in the hippocampus varies systematically from the septal pole (high resolution) to the temporal pole (low resolution). Place fields get progressively larger, and the probability of observing a field in a given environment gets progressively smaller. It was previously found that decoupling movement in space from ambulation, by having the animal actively ride on a mobile platform, results in marked enlargement of the spatial scale factor in the dorsal hippocampus and a reduction in the increase in theta rhythm power with running speed, suggesting that a self-motion signal determines the spatial scale at which the hippocampal population vector updates. These results led to the hypothesis that the gain of the self-motion signal may vary systematically along the septo-temporal axis of the hippocampus. To test this hypothesis, EEG theta rhythm and ensembles of CA1 pyramidal cells and interneurons were recorded from the extreme dorsal and middle portions of the hippocampus. Pyramidal cell population vectors representing successive locations became decorrelated over substantially shorter distances in the dorsal than in the middle hippocampus. Dorsal pyramidal cells had smaller place fields, higher mean and peak firing rates, and higher intrinsic oscillation frequencies during track running than that of middle pyramidal cells. Both dorsal pyramidal cells and interneurons had more elevated mean rates during running, compared with rest, than that of the corresponding cell classes in the middle hippocampus, and both cell classes increased their rates more as a function of speed in the dorsal hippocampus. The amplitude, but not the frequency of fissure recorded theta rhythm, increased more as a function of running speed in the dorsal than in the middle hippocampus. We conclude that variation in the neuronal response to movement speed is the likely basis for the systematic variation in spatial scaling along the septo-temporal axis of the hippocampus. © 2005 Wiley-Liss, Inc. [source]


Model of frequent, recurrent, and spontaneous seizures in the intact mouse hippocampus

HIPPOCAMPUS, Issue 8 2004
M. Derchansky
Abstract This study presents a model of chronic, recurrent, spontaneous seizures in the intact isolated hippocampal preparation from mice aged P8,P25. Field activity from the CA1 pyramidal cell layer was recorded and recurrent, spontaneous seizure-like events (SLEs) were observed in the presence of low Mg2+ (0.25 mM) artificial cerebrospinal fluid (ACSF). Hippocampi also showed interictal epileptiform discharges (IEDs) of 0.9,4.2 Hz occurring between seizures. No age-specific differences were found in SLE occurrence (2 SLEs per 10 min, on average), duration, and corresponding frequencies. After long exposure to low Mg2+ ACSF (>3 h), SLEs were completely reversible within minutes with the application of normal (2 mM Mg2+) ACSF. The AMPA antagonist, CNQX, blocked all epileptiform activity, whereas the NMDA antagonist, APV, did not. The ,-aminobutyric acid (GABA)A antagonist, bicuculline, attenuated and fragmented SLEs, implicating interneurons in SLE generation. The L-type Ca2+ blocker, nifedipine, enhanced epileptiform activity. Analysis of dual site recordings along the septotemporal hippocampus demonstrated that epileptiform activity began first in the temporal pole of the hippocampus, as illustrated by disconnection experiments. Once an SLE had been established, however, the septal hippocampus was sometimes seen to lead the epileptiform activity. The whole hippocampus with intact local circuitry, treated with low Mg2+, provides a realistic model of recurrent spontaneous seizures, which may be used, in normal and genetically modified mice, to study the dynamics of seizures and seizure evolution, as well as the mechanisms of action of anti-epileptic drugs and other therapeutic modalities. © 2004 Wiley-Liss, Inc. [source]


Attachment style, affective loss and gray matter volume: A voxel-based morphometry study

HUMAN BRAIN MAPPING, Issue 10 2010
Stefania Benetti
Abstract Early patterns of infant attachment have been shown to be an important influence on adult social behavior. Animal studies suggest that patterns of early attachment influence brain development, contributing to permanent alterations in neural structure; however, there are no previous studies investigating whether differences in attachment style are associated with differences in brain structure in humans. In this study, we used Magnetic Resonance Imaging (MRI) and voxel-based morphometry (VBM) to examine for the first time the association between attachment style, affective loss (for example, death of a loved one) and gray matter volume in a healthy sample of adults (n = 32). Attachment style was assessed on two dimensions (anxious and avoidant) using the ECR-Revised questionnaire. High attachment-related anxiety was associated with decreased gray matter in the anterior temporal pole and increased gray matter in the left lateral orbital gyrus. A greater number of affective losses was associated with increased gray matter volume in the cerebellum; in this region, however, the impact of affective losses was significantly moderated by the level of attachment-related avoidance. These findings indicate that differences in attachment style are associated with differences in the neural structure of regions implicated in emotion regulation. It is hypothesized that early attachment experience may contribute to structural brain differences associated with attachment style in adulthood; furthermore, these findings point to a neuronal mechanism through which attachment style may mediate individual differences in responses to affective loss. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [source]


A role for left temporal pole in the retrieval of words for unique entities

HUMAN BRAIN MAPPING, Issue 4 2001
Thomas J. Grabowski
Abstract Both lesion and functional imaging studies have implicated sectors of high-order association cortices of the left temporal lobe in the retrieval of words for objects belonging to varied conceptual categories. In particular, the cortices located in the left temporal pole have been associated with naming unique persons from faces. Because this neuroanatomical-behavioral association might be related to either the specificity of the task (retrieving a name at unique level) or to the possible preferential processing of faces by anterior temporal cortices, we performed a PET imaging experiment to test the hypothesis that the effect is related to the specificity of the word retrieval task. Normal subjects were asked to name at unique level entities from two conceptual categories: famous landmarks and famous faces. In support of the hypothesis, naming entities in both categories was associated with increases in activity in the left temporal pole. No main effect of category (faces vs. landmarks/buildings) or interaction of task and category was found in the left temporal pole. Retrieving names for unique persons and for names for unique landmarks activate the same brain region. These findings are consistent with the notion that activity in the left temporal pole is linked to the level of specificity of word retrieval rather than the conceptual class to which the stimulus belongs. Hum. Brain Mapping 13:199,212, 2001. © 2001 Wiley-Liss, Inc. [source]


Human cortical processing of colour and pattern

HUMAN BRAIN MAPPING, Issue 4 2001
Nicholas A. Barrett
Abstract The present study investigates human visual processing of simple two-colour patterns using a delayed match to sample paradigm with positron emission tomography (PET). This study is unique in that we specifically designed the visual stimuli to be the same for both pattern and colour recognition with all patterns being abstract shapes not easily verbally coded composed of two-colour combinations. We did this to explore those brain regions required for both colour and pattern processing and to separate those areas of activation required for one or the other. We found that both tasks activated similar occipital regions, the major difference being more extensive activation in pattern recognition. A right-sided network that involved the inferior parietal lobule, the head of the caudate nucleus, and the pulvinar nucleus of the thalamus was common to both paradigms. Pattern recognition also activated the left temporal pole and right lateral orbital gyrus, whereas colour recognition activated the left fusiform gyrus and several right frontal regions. Hum. Brain Mapping 13:213,225, 2001. © 2001 Wiley-Liss, Inc. [source]


Effects of smoking marijuana on focal attention and brain blood flow

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2007
Daniel S. O'Leary
Abstract Using an attention task to control cognitive state, we previously found that smoking marijuana changes regional cerebral blood flow (rCBF). The present study measured rCBF during tasks requiring attention to left and right ears in different conditions. Twelve occasional marijuana users (mean age 23.5 years) were imaged with PET using [15O]water after smoking marijuana or placebo cigarettes as they performed a reaction time (RT) baseline task, and a dichotic listening task with attend-right- and attend-left-ear instructions. Smoking marijuana, but not placebo, resulted in increased normalized rCBF in orbital frontal cortex, anterior cingulate, temporal pole, insula, and cerebellum. RCBF was reduced in visual and auditory cortices. These changes occurred in all three tasks and replicated our earlier studies. They appear to reflect the direct effects of marijuana on the brain. Smoking marijuana lowered rCBF in auditory cortices compared to placebo but did not alter the normal pattern of attention-related rCBF asymmetry (i.e., greater rCBF in the temporal lobe contralateral to the direction of attention) that was also observed after placebo. These data indicate that marijuana has dramatic direct effects on rCBF, but causes relatively little change in the normal pattern of task-related rCBF on this auditory focused attention task. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Cytoarchitectonic and chemoarchitectonic subdivisions of the perirhinal and parahippocampal cortices in macaque monkeys

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2007
Kadharbatcha S. Saleem
Abstract Although the perirhinal and parahippocampal cortices have been shown to be critically involved in memory processing, the boundaries and extent of these areas have been controversial. To produce a more objective and reproducible description, the architectonic boundaries and structure of the perirhinal (areas 35 and 36) and parahippocampal (areas TF and TH) cortices were analyzed in three macaque species, with four different staining methods [Nissl and immunohistochemistry for parvalbumin, nonphosphorylated neurofilaments (with SMI-32), and the m2 muscarinic acetylcholine receptor]. We further correlated the architectonic boundary of the parahippocampal cortex with connections to and from different subregions of anterior area TE and with previously published connections with the prefrontal cortex and temporal pole (Kondo et al. [2005] J. Comp. Neurol. 493:479,509). Together, these data provided a clear delineation of the perirhinal and parahippocampal areas, although it differs from previous descriptions. In particular, we did not extend the perirhinal cortex into the temporal pole, and the lateral boundaries of areas 36 and TF with area TE were placed more medially than in other studies. The lateral boundary of area TF in Macaca fuscata was located more laterally than in Macaca fascicularis or Macaca mulatta, although there was no difference in architectonic structure. We recognized a caudal, granular part of the parahippocampal cortex that we termed "area TFO." This area closely resembles the laterally adjacent area TE and the caudally adjacent area V4 but is clearly different from the more rostral area TF. These areas are likely to have distinct functions. J. Comp. Neurol. 500:973,1006, 2007. © 2006 Wiley-Liss, Inc. [source]


Functional segregation of cortical language areas by sentence repetition

HUMAN BRAIN MAPPING, Issue 5 2006
Ghislaine Dehaene-Lambertz
Abstract The functional organization of the perisylvian language network was examined using a functional MRI (fMRI) adaptation paradigm with spoken sentences. In Experiment 1, a given sentence was presented every 14.4 s and repeated two, three, or four times in a row. The study of the temporal properties of the BOLD response revealed a temporal gradient along the dorsal,ventral and rostral,caudal directions: From Heschl's gyrus, where the fastest responses were recorded, responses became increasingly slower toward the posterior part of the superior temporal gyrus and toward the temporal poles and the left inferior frontal gyrus, where the slowest responses were observed. Repetition induced a decrease in amplitude and a speeding up of the BOLD response in the superior temporal sulcus (STS), while the most superior temporal regions were not affected. In Experiment 2, small blocks of six sentences were presented in which either the speaker voice or the linguistic content of the sentence, or both, were repeated. Data analyses revealed a clear asymmetry: While two clusters in the left superior temporal sulcus showed identical repetition suppression whether the sentences were produced by the same speaker or different speakers, the homologous right regions were sensitive to sentence repetition only when the speaker voice remained constant. Thus, hemispheric left regions encode linguistic content while homologous right regions encode more details about extralinguistic features like speaker voice. The results demonstrate the feasibility of using sentence-level adaptation to probe the functional organization of cortical language areas. Hum Brain Mapp, 2006. © 2006 Wiley-Liss, Inc. [source]


Retrieving meaning after temporal lobe infarction: The role of the basal language area

ANNALS OF NEUROLOGY, Issue 6 2004
David J. Sharp MRCP
During speech comprehension the auditory association cortex in the superior temporal cortex is involved in perceptual analysis of the speech signal, whereas the basal language area in the inferior temporal cortex mediates access to word meaning. Disruption of the interaction between the superior and inferior temporal cortices is one factor that may determine recovery from aphasic stroke. We used positron emission tomography to investigate semantic processing within inferior temporal cortex in control subjects and after infarction involving the superior temporal cortex. In the control group, semantic decision making on clear speech activated both anterior fusiform gyri. Chronic aphasic patients were impaired at the task and demonstrated reduced activation within the left anterior fusiform gyrus. A similar pattern of impaired performance and reduced left anterior fusiform gyrus activation was observed when control subjects heard perceptually degraded speech. Performance in both groups predicted activity in the right anterior fusiform gyrus and the temporal poles, where accuracy linearly correlated with activity. These results demonstrate that the function of the basal language area is sensitive to changes in the quality of perceptual input. In addition, different profiles of response observed in each hemisphere suggest distinct contributions of both left and right inferior temporal cortices to the semantic processing of speech. Ann Neurol 2004 [source]