DOCSLIB.ORG

An Event-Related Functional Magnetic Resonance Imaging Study

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
An Event-Related Functional Magnetic Resonance Imaging Study Neural Correlates of Memory for Items and for Associations: An Event-related Functional Magnetic Resonance Imaging Study Ame´lie M. Achim and Martin Lepage Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/17/4/652/1757197/0898929053467578.pdf by guest on 18 May 2021 Abstract & Although results from cognitive psychology, neuropsychol- coding, greater prefrontal, hippocampal, and parietal activation ogy, and behavioral neuroscience clearly suggest that item was observed for associations, but no significant activation was and associative information in memory rely on partly different observed for items at the selected threshold. During recog- brain regions, little is known concerning the differences and nition, greater activation was observed for associative trials in similarities that exist between these two types of information as the left dorsolateral prefrontal cortex and superior parietal a function of memory stage (i.e., encoding and retrieval). We lobules bilaterally, whereas item recognition trials showed used event-related functional magnetic resonance imaging to greater activation of bilateral frontal regions, bilateral anterior assess neural correlates of item and associative encoding and medial temporal areas, and the right temporo-parietal junction. retrieval of simple images in 18 healthy subjects. During en- Post hoc analyses suggested that the anterior medial temporal coding, subjects memorized items and pairs. During retrieval, activation observed during item recognition was driven mainly subjects made item recognition judgments (old vs. new) and by new items, confirming a role for this structure in novelty de- associative recognition judgments (intact vs. rearranged). Rel- tection. These results suggest that although some structures ative to baseline, item and associative trials activated bilateral such as the medial temporal and prefrontal cortex play a gen- medial temporal and prefrontal regions during both encoding eral role in memory, the pattern of activation in these regions and retrieval. Direct contrasts were then performed between can be modulated by the type of information (items or associa- item and associative trials for each memory stage. During en- tions) interacting with memory stages. & INTRODUCTION view that item and associative information are distinc- An increasing amount of empirical evidence suggests tively processed in memory. It follows that memory for that episodic memories are formed of two main types of these two types of information could rely, at least in part, information: (1) information about individual items and on different brain regions. (2) information about the associations that these items Already, there are a number of findings that support maintain with each other and with their physical (e.g., this inference. Lesion studies in both rodents (Brown & color) or spatio-temporal (e.g., position in space) charac- Aggleton, 2001; Eichenbaum, Otto, & Cohen, 1994; teristics. These two types of information have been Cohen & Eichenbaum, 1993) and humans (Mayes et al., termed item memory and associative (relational) 2001; Mayes, van Eijk, Gooding, Isaac, & Holdstock, 1999; memory, respectively (Murdock, 1982; Humphreys, 1976, Vargha-Khadem et al., 1997) suggest that the hippocam- 1978). Although item and associative memory obviously pus plays a critical role in associative memory, but not share some common underlying episodic memory pro- in item memory. However, item memory is not com- cesses, there could also be some difference in the pro- pletely spared in patients with hippocampal damage, and cessing of these two types of information. For instance, some have argued that the hippocampus could be sim- the longer response times observed during the retrieval ilarly involved in both types of memory (Stark, Bayley, & of associative information relative to item information Squire, 2002; Stark & Squire, 2000, 2001). The prefrontal (Hockley, 1991; Gronlund & Ratcliff, 1989), the greater cortex could also be involved in associative memory as persistence of associative memory over time (Hockley, suggested by other neuropsychological studies that 1991, 1992), and the documentation of distinct receiver have shown that patients with frontal lobe lesions are operating characteristics (Yonelinas, 1997) attests to the relatively more impaired in tasks of associative memory relative to item memory (Johnson, O’Connor, & Cantor, 1997; Janowsky, Shimamura, & Squire, 1989). Lesion McGill University and Douglas Hospital Research Centre, studies, however, do not give information about which Quebec, Canada memory stage is affected. Indeed, the deficits could D 2005 Massachusetts Institute of Technology Journal of Cognitive Neuroscience 17:4, pp. 652–667 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/0898929053467578 by guest on 24 September 2021 reflect that (1) associative information is not success- item, B could be either another item or a feature fully encoded and, thus, cannot be retrieved, (2) asso- associated with A. ciative information has been correctly encoded but In the study by Yonelinas et al. (2001), individual cannot be accessed because of retrieval deficits, or (3) items (black and white images) were presented during both associative encoding and retrieval are impaired. the recognition test and subjects were asked to judge Thus, studying the distinction between item and asso- whether each item was old or new (item recognition) or ciative memory during both encoding and retrieval to judge whether each stimulus was initially presented in should lead to a better understanding of the processes red or green (associative recognition). The associative that support these two types of memory. More specifi- recognition task did not require subjects to distinguish cally, some brain regions could be involved in item or between intact and rearranged associations but instead Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/17/4/652/1757197/0898929053467578.pdf by guest on 18 May 2021 associative memory regardless of the memory stage, but it required them to recall the color initially associated other brain regions could be specifically involved in with each item. When these associative recognition trials encoding or retrieval of a certain type of information. were contrasted to old item recognition trials, hippo- An important advantage of functional brain imaging campal activation was observed. It is, therefore, possible techniques is that they enable us to examine encoding that the demands of generating the initial association, and retrieval separately while looking at the whole brain. not the recognition of associative information per se, During encoding, two main strategies have been adopted resulted in hippocampal activation in this experiment. In to distinguish brain activation specific to associative or the study by Tsukiura et al. (2002), the associative item-oriented encoding. The first strategy is to give the recognition task that gave rise to left parahippocampal subjects different instructions, with one set of instruc- activation might have also involved the generation of tions promoting associative encoding and the other additional associative information. During encoding, set of instructions promoting individual or nonassocia- the subjects were presented with comic strips formed tive encoding. Another strategy is to present stimuli that of 4 images. During recognition, they were cued with either encourage (e.g., pairs of items) or hinder (e.g., in- 2 images and asked to judge whether these images were dividual items) associative encoding. The neuroimaging from the same strip (associative recognition) or whether studies that have used either of these two strategies have both images had been studied before (item recogni- consistently reported greater hippocampal and prefron- tion). It is quite possible that the subjects tried to re- tal activation for associative relative to item encoding member the missing images from the same strip to (Davachi & Wagner, 2002; Davachi, Maril, & Wagner, facilitate their associative recognition judgments. Thus, 2001; Killgore, Casasanto, Yurgelun-Todd, Maldjian, & although the hippocampus is clearly implicated in asso- Detre, 2000; Henke, Weber, Kneifel, Wieser, & Buck, ciative encoding, it is still unclear whether activity in the 1999; Montaldi et al., 1998; Henke, Buck, Weber, & medial temporal lobe can be justifiably linked to asso- Wieser, 1997; Kapur et al., 1996; Vandenberghe, Price, ciative recognition. Wise, Josephs, & Frackowiak, 1996). Because episodic memory encoding and retrieval are During recognition, the most consistent finding is supported by partially different brain regions, and be- greater left prefrontal activation for associative relative cause the activation of specific brain regions (e.g., those to item recognition (Lepage, Brodeur, & Bourgouin, implicated in the processing of item or associative 2003; Badgaiyan, Schacter, & Alpert, 2002; Rugg, Fletch- information) typically depends on the pattern of activa- er, Chua, & Dolan, 1999; Nolde, Johnson, & D’Esposito, tion elsewhere in the brain (McIntosh, 2000), brain 1998; Cabeza et al., 1997), although right prefrontal regions supporting item and associative memory are activation has also been observed (Lepage et al., 2003; likely to differ between encoding and retrieval. It follows Rugg et al., 1999; Cabeza et al., 1997). In contrast to the that studying both encoding and retrieval in the same consistent prefrontal activation, only a few
Load more

Recommended publications
  • Lesions of Perirhinal and Parahippocampal Cortex That Spare the Amygdala and Hippocampal Formation Produce Severe Memory Impairment
    The Journal of Neuroscience, December 1989, 9(12): 4355-4370 Lesions of Perirhinal and Parahippocampal Cortex That Spare the Amygdala and Hippocampal Formation Produce Severe Memory Impairment Stuart Zola-Morgan,’ Larry Ft. Squire,’ David G. Amaral,2 and Wendy A. Suzuki2J Veterans Administration Medical Center, San Diego, California, 92161, and Department of Psychiatry, University of California, San Diego, La Jolla, California 92093, The Salk Institute, San Diego, California 92136, and 3Group in Neurosciences, University of California, San Diego, La Jolla, California 92093 In monkeys, bilateral damage to the medial temporal region Moss, 1984). (In this notation, H refers to the hippocampus, A produces severe memory impairment. This lesion, which in- to the amygdala, and the plus superscript (+) to the cortical cludes the hippocampal formation, amygdala, and adjacent tissue adjacent to each structure.) This lesion appears to con- cortex, including the parahippocampal gyrus (the H+A+ le- stitute an animal model of medial temporal lobe amnesia like sion), appears to constitute an animal model of human me- that exhibited by the well-studied patient H.M. (Scoville and dial temporal lobe amnesia. Reexamination of histological Milner, 1957). material from previously studied monkeys with H+A+ lesions The H+A+ lesion produces greater memory impairment than indicated that the perirhinal cortex had also sustained sig- a lesion limited to the hippocampal formation and parahip- nificant damage. Furthermore, recent neuroanatomical stud- pocampal cortex-the H+ lesion (Mishkin, 1978; Mahut et al., ies show that the perirhinal cortex and the closely associated 1982; Zola-Morgan and Squire, 1985, 1986; Zola-Morgan et al., parahippocampal cortex provide the major source of cortical 1989a).
    [Show full text]
  • Toward a Common Terminology for the Gyri and Sulci of the Human Cerebral Cortex Hans Ten Donkelaar, Nathalie Tzourio-Mazoyer, Jürgen Mai
    Toward a Common Terminology for the Gyri and Sulci of the Human Cerebral Cortex Hans ten Donkelaar, Nathalie Tzourio-Mazoyer, Jürgen Mai To cite this version: Hans ten Donkelaar, Nathalie Tzourio-Mazoyer, Jürgen Mai. Toward a Common Terminology for the Gyri and Sulci of the Human Cerebral Cortex. Frontiers in Neuroanatomy, Frontiers, 2018, 12, pp.93. 10.3389/fnana.2018.00093. hal-01929541 HAL Id: hal-01929541 https://hal.archives-ouvertes.fr/hal-01929541 Submitted on 21 Nov 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. REVIEW published: 19 November 2018 doi: 10.3389/fnana.2018.00093 Toward a Common Terminology for the Gyri and Sulci of the Human Cerebral Cortex Hans J. ten Donkelaar 1*†, Nathalie Tzourio-Mazoyer 2† and Jürgen K. Mai 3† 1 Department of Neurology, Donders Center for Medical Neuroscience, Radboud University Medical Center, Nijmegen, Netherlands, 2 IMN Institut des Maladies Neurodégénératives UMR 5293, Université de Bordeaux, Bordeaux, France, 3 Institute for Anatomy, Heinrich Heine University, Düsseldorf, Germany The gyri and sulci of the human brain were defined by pioneers such as Louis-Pierre Gratiolet and Alexander Ecker, and extensified by, among others, Dejerine (1895) and von Economo and Koskinas (1925).
    [Show full text]
  • Involvement of Human Left Dorsolateral Prefrontal Cortex in Perceptual Decision Making Is Independent of Response Modality
    Involvement of human left dorsolateral prefrontal cortex in perceptual decision making is independent of response modality H. R. Heekeren*†‡§, S. Marrett¶, D. A. Ruff*, P. A. Bandettini*¶, and L. G. Ungerleider*ʈ *Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892-9663; †Max Planck Institute for Human Development, 14195 Berlin, Germany; ‡Max Planck Institute for Human Cognitive and Brain Sciences, 04103 Leipzig, Germany; §Berlin NeuroImaging Center, Charite´University Medicine Berlin, 10117 Berlin, Germany; and ¶Functional MRI Facility, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892-9663 Contributed by L. G. Ungerleider, May 12, 2006 Perceptual decision making typically entails the processing of such as the DLPFC, during high-motion-coherence trials, i.e., trials sensory signals, the formation of a decision, and the planning and in which the sensory evidence is greatest, than during low- execution of a motor response. Although recent studies in mon- coherence trials. keys and humans have revealed possible neural mechanisms for As in the visual system, in the somatosensory system, in a task perceptual decision making, much less is known about how the in which the monkey must decide which of two vibratory stimuli decision is subsequently transformed into a motor action and has a higher frequency, the monkey’s decision can be predicted whether or not the decision is represented at an abstract level, i.e., by subtracting the activities of two populations of sensory independently of the specific motor response. To address this neurons in the secondary somatosensory cortex (SII) that prefer issue, we used functional MRI to monitor changes in brain activity high and low frequencies, respectively (10).
    [Show full text]
  • Default Mode Network in Childhood Autism Posteromedial Cortex Heterogeneity and Relationship with Social Deficits
    ARCHIVAL REPORT Default Mode Network in Childhood Autism: Posteromedial Cortex Heterogeneity and Relationship with Social Deficits Charles J. Lynch, Lucina Q. Uddin, Kaustubh Supekar, Amirah Khouzam, Jennifer Phillips, and Vinod Menon Background: The default mode network (DMN), a brain system anchored in the posteromedial cortex, has been identified as underconnected in adults with autism spectrum disorder (ASD). However, to date there have been no attempts to characterize this network and its involvement in mediating social deficits in children with ASD. Furthermore, the functionally heterogeneous profile of the posteromedial cortex raises questions regarding how altered connectivity manifests in specific functional modules within this brain region in children with ASD. Methods: Resting-state functional magnetic resonance imaging and an anatomically informed approach were used to investigate the functional connectivity of the DMN in 20 children with ASD and 19 age-, gender-, and IQ-matched typically developing (TD) children. Multivariate regression analyses were used to test whether altered patterns of connectivity are predictive of social impairment severity. Results: Compared with TD children, children with ASD demonstrated hyperconnectivity of the posterior cingulate and retrosplenial cortices with predominately medial and anterolateral temporal cortex. In contrast, the precuneus in ASD children demonstrated hypoconnectivity with visual cortex, basal ganglia, and locally within the posteromedial cortex. Aberrant posterior cingulate cortex hyperconnectivity was linked with severity of social impairments in ASD, whereas precuneus hypoconnectivity was unrelated to social deficits. Consistent with previous work in healthy adults, a functionally heterogeneous profile of connectivity within the posteromedial cortex in both TD and ASD children was observed. Conclusions: This work links hyperconnectivity of DMN-related circuits to the core social deficits in young children with ASD and highlights fundamental aspects of posteromedial cortex heterogeneity.
    [Show full text]
  • Functional Connectivity of the Precuneus in Unmedicated Patients with Depression
    Biological Psychiatry: CNNI Archival Report Functional Connectivity of the Precuneus in Unmedicated Patients With Depression Wei Cheng, Edmund T. Rolls, Jiang Qiu, Deyu Yang, Hongtao Ruan, Dongtao Wei, Libo Zhao, Jie Meng, Peng Xie, and Jianfeng Feng ABSTRACT BACKGROUND: The precuneus has connectivity with brain systems implicated in depression. METHODS: We performed the first fully voxel-level resting-state functional connectivity (FC) neuroimaging analysis of depression of the precuneus, with 282 patients with major depressive disorder and 254 control subjects. RESULTS: In 125 unmedicated patients, voxels in the precuneus had significantly increased FC with the lateral orbitofrontal cortex, a region implicated in nonreward that is thereby implicated in depression. FC was also increased in depression between the precuneus and the dorsolateral prefrontal cortex, temporal cortex, and angular and supramarginal areas. In patients receiving medication, the FC between the lateral orbitofrontal cortex and precuneus was decreased back toward that in the control subjects. In the 254 control subjects, parcellation revealed superior anterior, superior posterior, and inferior subdivisions, with the inferior subdivision having high connectivity with the posterior cingulate cortex, parahippocampal gyrus, angular gyrus, and prefrontal cortex. It was the ventral subdivision of the precuneus that had increased connectivity in depression with the lateral orbitofrontal cortex and adjoining inferior frontal gyrus. CONCLUSIONS: The findings support the theory that the system in the lateral orbitofrontal cortex implicated in the response to nonreceipt of expected rewards has increased effects on areas in which the self is represented, such as the precuneus. This may result in low self-esteem in depression. The increased connectivity of the precuneus with the prefrontal cortex short-term memory system may contribute to the rumination about low self-esteem in depression.
    [Show full text]
  • Relationships Between Hippocampal Atrophy, White Matter Disruption, and Gray Matter Hypometabolism in Alzheimer's Disease
    6174 • The Journal of Neuroscience, June 11, 2008 • 28(24):6174–6181 Neurobiology of Disease Relationships between Hippocampal Atrophy, White Matter Disruption, and Gray Matter Hypometabolism in Alzheimer’s Disease Nicolas Villain,1 Be´atrice Desgranges,1 Fausto Viader,1,2 Vincent de la Sayette,1,2 Florence Me´zenge,1 Brigitte Landeau,1 Jean-Claude Baron,3 Francis Eustache,1 and Gae¨l Che´telat1 1Institut National de la Sante´ et de la Recherche Me´dicale–Ecole Pratique des Hautes Etudes–Universite´ de Caen/Basse-Normandie, Unite´ U923, Groupement d’Inte´reˆt Public Cyceron, Centre Hospitalier Universitaire (CHU) Coˆte de Nacre, 14074 Caen, France, 2De´partement de Neurologie, CHU Coˆte de Nacre, 14033 Caen Cedex, France, and 3Department of Clinical Neurosciences, Neurology Unit, University of Cambridge, Cambridge CB2 2SP, United Kingdom In early Alzheimer’s disease (AD), the hippocampal region is the area most severely affected by cellular and structural alterations, yet glucose hypometabolism predominates in the posterior association cortex and posterior cingulate gyrus. One prevalent hypothesis to account for this discrepancy is that posterior cingulate hypometabolism results from disconnection from the hippocampus through disruptionofthecingulumbundle.However,onlypartialandindirectevidencecurrentlysupportsthishypothesis.Thus,usingstructural 18 magnetic resonance imaging and 2-[ F]fluoro-2-deoxy-D-glucose positron emission tomography in 18 patients with early AD, we assessed the relationships between hippocampal atrophy, white matter integrity, and gray matter metabolism by means of a whole-brain voxel-based correlative approach. We found that hippocampal atrophy is specifically related to cingulum bundle disruption, which is in turn highly correlated to hypometabolism of the posterior cingulate cortex but also of the middle cingulate gyrus, thalamus, mammillary bodies, parahippocampal gyrus, and hippocampus (all part of Papez’s circuit), as well as the right temporoparietal associative cortex.
    [Show full text]
  • Increased Functional Connectivity of the Posterior Cingulate Cortex with the Lateral Orbitofrontal Cortex in Depression Wei Cheng1, Edmund T
    Cheng et al. Translational Psychiatry (2018) 8:90 DOI 10.1038/s41398-018-0139-1 Translational Psychiatry ARTICLE Open Access Increased functional connectivity of the posterior cingulate cortex with the lateral orbitofrontal cortex in depression Wei Cheng1, Edmund T. Rolls2,3,JiangQiu4,5, Xiongfei Xie6,DongtaoWei5, Chu-Chung Huang7,AlbertC.Yang8, Shih-Jen Tsai 8,QiLi9,JieMeng5, Ching-Po Lin 1,7,10,PengXie9,11,12 and Jianfeng Feng1,2,13 Abstract To analyze the functioning of the posterior cingulate cortex (PCC) in depression, we performed the first fully voxel- level resting state functional-connectivity neuroimaging analysis of depression of the PCC, with 336 patients with major depressive disorder and 350 controls. Voxels in the PCC had significantly increased functional connectivity with the lateral orbitofrontal cortex, a region implicated in non-reward and which is thereby implicated in depression. In patients receiving medication, the functional connectivity between the lateral orbitofrontal cortex and PCC was decreased back towards that in the controls. In the 350 controls, it was shown that the PCC has high functional connectivity with the parahippocampal regions which are involved in memory. The findings support the theory that the non-reward system in the lateral orbitofrontal cortex has increased effects on memory systems, which contribute to the rumination about sad memories and events in depression. These new findings provide evidence that a key target to ameliorate depression is the lateral orbitofrontal cortex. 1234567890():,; 1234567890():,; Introduction pathophysiology of major depression and it appears to be Depression characterized by persistently sad or related to rumination and depression severity in MDD6.
    [Show full text]
  • Anatomic Moment Limbic System Anatomy: an Overview
    Anatomic Moment Limbic System Anatomy: An Overview Leighton P. Mark,1.3 David L. Daniels, 1 Thomas P. Naidich,2 and Jessica A. Borne1 The anatomy of the limbic system has become shaped sulcus (Fig. 2) designated as 1) the hip­ more relevant due to the development of high pocampal fissure where it lies superior to the resolution and functional magnetic resonance parahippocampal gyrus, and 2) the callosal sulcus (MR) imaging. This review is the first of a series where it lies inferior to the cingulate gyrus of Anatomic Moments designed to highlight se­ (Fig. 3). lected features of limbic system anatomy in order Nested within this )-shaped sulcus is another )­ to facilitate their application to MR interpretation. shaped structure formed by 1) the dentate gyrus Limbic system terminology of early anatomists and hippocampus in the temporal lobe (Figs. 2 was largely descriptive (Table 1), but the nomen­ and 4), 2) the hippocampal tail which consists of clature used in this series will follow that of recent thin gray and white matter structures located just authors (Table 2) (1-7). posterior and inferior to the splenium of the In accordance with the curvilinear development corpus callosum (Fig. 5), and 3) the supracallosal of the cerebral hemispheres (Fig. 1), the struc­ gyrus which is located inferior to the callosal tures of the limbic lobe form a series of "nested" sulcus. The supracallosal gyrus is intimately ap­ )-shaped curves (Fig. 2). plied to the upper surface of the corpus callosum, The widest curve is formed by the large limbic and contains gray matter termed the indusium gyrus which is designated as 1) the parahippo­ griseum (Fig.
    [Show full text]
  • Invasive Neuromodulation As a Possible Treatment for Tinnitus
    Invasive neuromodulation as a possible treatment for tinnitus Celine Marechal Student number: 01308534 Supervisor(s): Prof. Dr. Ingeborg Dhooge, Prof. Dr. Dirk Van Roost, Dr. Ann Deklerck A dissertation submitted to Ghent University in partial fulfilment of the requirements for the degree of Master of Medicine in Medicine Academic year: 2017 – 2018 Deze pagina is niet beschikbaar omdat ze persoonsgegevens bevat. Universiteitsbibliotheek Gent, 2021. This page is not available because it contains personal information. Ghent Universit , Librar , 2021. Table of contents 1. Abstract .......................................................................................................................... 1 Samenvatting ........................................................................................................................ 2 2. Introduction .................................................................................................................... 4 2.1 Epidemiology and classification of tinnitus ................................................................... 4 2.2 Physiology of the auditory system ............................................................................... 4 2.2.1 Classical auditory pathway .................................................................................... 4 2.2.2 Non-classical auditory pathway ............................................................................. 5 2.3 Pathophysiology of tinnitus .........................................................................................
    [Show full text]
  • Subtemporal Transparahippocampal Amygdalohippocampectomy for Surgical Treatment of Mesial Temporal Lobe Epilepsy Technical Note
    Subtemporal transparahippocampal amygdalohippocampectomy for surgical treatment of mesial temporal lobe epilepsy Technical note T. S. Park, M.D., Blaise F. D. Bourgeois, M.D., Daniel L. Silbergeld, M.D., and W. Edwin Dodson, M.D. Department of Neurology and Neurological Surgery, Washington University School of Medicine, and St. Louis Children's Hospital, St. Louis, Missouri Amygdalohippocampectomy (AH) is an accepted surgical option for treatment of medically refractory mesial temporal lobe epilepsy. Operative approaches to the amygdala and hippocampus that previously have been reported include: the sylvian fissure, the superior temporal sulcus, the middle temporal gyrus, and the fusiform gyrus. Regardless of the approach, AH permits not only extirpation of an epileptogenic focus in the amygdala and anterior hippocampus, but interruption of pathways of seizure spread via the entorhinal cortex and the parahippocampal gyrus. The authors report a modification of a surgical technique for AH via the parahippocampal gyrus, in which excision is limited to the anterior hippocampus, amygdala and parahippocampal gyrus while preserving the fusiform gyrus and the rest of the temporal lobe. Because transparahippocampal AH avoids injury to the fusiform gyrus and the lateral temporal lobe, it can be performed without intracarotid sodium amobarbital testing of language dominance and language mapping. Thus the operation would be particularly suitable for pediatric patients in whom intraoperative language mapping before resection is difficult. Key Words * amygdalohippocampectomy * complex partial seizure * parahippocampal gyrus * subtemporal approach Currently several different variations of temporal lobe resections are used for medically intractable complex partial seizures.[4,6,8,18,21,30,34] Among these operations is amygdalohippocampectomy (AH), first described in 1958 by Niemeyer,[16] who approached the amygdala and hippocampus through an incision on the middle temporal gyrus.
    [Show full text]
  • The Effect of Parietal Stimulation on Hippocampal-Cortical Rsfc and Episodic Memory Is Associated with Fractional Anisotropy in Multiple Stimulation Site Pathways
    bioRxiv preprint doi: https://doi.org/10.1101/2020.07.09.195172; this version posted July 10, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license. Full title: The effect of parietal stimulation on hippocampal-cortical rsFC and episodic memory is associated with fractional anisotropy in multiple stimulation site pathways. Abbreviated title: DTI and hippocampal network enhancement Author List *Michael Freedberg, Ph.D.1 [email protected] Catherine A. Cunningham, B.S.1 [email protected] Cynthia M. Fioriti, B.S. 1 [email protected] Jorge Dorado Murillo, B.S.1 [email protected] Jack A. Reeves, B.Ch.E. 1 [email protected] Paul A. Taylor, Ph.D. 2 [email protected] Joelle E. Sarlls, Ph.D. 3 [email protected] Eric M. Wassermann, M.D.1 [email protected] Affiliations: 1. Behavioral Neurology Unit, NINDS, Bethesda, MD, USA, 20892 2. Scientific and Statistical Computing Core, NIMH, NIH, Bethesda, MD, USA 3. NIH MRI Research Facility, NINDS, NIH, Bethesda, MD, USA *Corresponding Author Information: 9000 Rockville Pike, 10 Center Drive, Rm. 7-5659, Bethesda, MD, 20850. Phone: 718-290-6729. Author Contributions: MF, EW, and JS designed the research. MF, JR, and CF Performed Research. MF, CC, JM, PT, and CF analyzed the data. All authors contributed to the manuscript. bioRxiv preprint doi: https://doi.org/10.1101/2020.07.09.195172; this version posted July 10, 2020.
    [Show full text]
  • An Event-Related Fmri Study
    www.elsevier.com/locate/ynimg NeuroImage 38 (2007) 212–222 Probing the transformation of discontinuous associations into episodic memory: An event-related fMRI study Shaozheng Qin,a,b,c Carinne Piekema,b,d Karl Magnus Petersson,b Buxin Han,a ⁎ ⁎ Jing Luo,a, and Guillén Fernándezb,e, aKey Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences (CAS), 100101 Beijing, China bF.C. Donders Centre for Cognitive Neuroimaging, Radboud University Nijmegen, 6500 HB Nijmegen, The Netherlands cGraduate School, Chinese Academy of Sciences (CAS), 100039 Beijing, China dHelmholtz Institute, Utrecht University, 3584 CS Utrecht, The Netherlands eDepartment of Neurology, University Medical Center Nijmegen, 6500 HB Nijmegen, The Netherlands Received 13 April 2007; revised 12 June 2007; accepted 12 July 2007 Available online 3 August 2007 Using event-related functional magnetic resonance imaging, we Introduction identified brain regions involved in storing associations of events discontinuous in time into long-term memory. Participants were The ability to associate and remember different aspects of an scanned while memorizing item-triplets including simultaneous and experience as one coherent episode is a critical feature of episodic discontinuous associations. Subsequent memory tests showed that memory (Tulving, 1983, 2002; Eichenbaum, 2004). In particular, it participants remembered both types of associations equally well. First, is crucial to bind and remember aspects of an experience that do not by constructing the contrast
    [Show full text]