The cognitive neuroscience of visual working memory

Visual working memory allows us to temporarily maintain and manipulate visual information in order to solve a task. The study of the brain mechanisms underlying this function began more than half a century ago, with Scoville and Milner’s (1957) seminal discoveries with amnesic patients. This timely collection of papers brings together diverse perspectives on the cognitive neuroscience of visual working memory from multiple fields that have traditionally been fairly disjointed: human neuroimaging, electrophysiological, behavioural and animal lesion studies, investigating both the developing and the adult brain

High frequency oscillations as a correlate of visual perception

“NOTICE: this is the author’s version of a work that was accepted for publication in International journal of psychophysiology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International journal of psychophysiology , 79, 1, (2011) DOI 10.1016/j.ijpsycho.2010.07.004Peer reviewedPostprin

www.fevertravel.ch: an online study prototype to evaluate the safety and feasibility of computerized guidelines for fever in returning travellers and migrants

Following the paper publication of practice guidelines for the management of febrile patients returning from the tropics, we constructed a consultation website that comprises a decision chart and specific diagnostic features providing medical diagnostic assistance to primary care physicians. We then integrated a research component to evaluate the implementation of these computerized guidelines. This study website has the same interface as the consultation website. In addition, one is able to record: (i) the pathway followed by the physician through the decision chart, (ii) the diagnostic tests performed, (iii) the initial and final diagnoses as well as outcome and (iv) reasons for non-adherence when the physician diverges from the proposed attitude. We believe that Internet technology is a powerful medium to reach physicians of different horizons in their own environment, and could prove to be an effective research tool to disseminate practice guidelines and evaluate their appropriateness. Here we describe the design, content, architecture and system implementation of this interactive study prototype aimed at integrating operational research in primary care practice. [Authors]]]> Emigration and Immigration; Fever; Guidelines as Topic; Internet; Travel eng oai:serval.unil.ch:BIB_4BBC99034368 2022-05-07T01:17:24Z ehelvetica openaire documents phdthesis urnserval <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_4BBC99034368 Usage conditionnel et inconditionnel des droits humains dans la vie quotidienne Anex, Emmanuelle Université de Lausanne, Faculté des sciences sociales et politiques info:eu-repo/semantics/doctoralThesis phdthesis 2018 fre https://serval.unil.ch/resource/serval:BIB_4BBC99034368.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_4BBC990343683 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_4BBC990343683 info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_4BA5F44A285D 2022-05-07T01:17:24Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_4BA5F44A285D A double-blind, placebo-controlled study of citalopram with and without lithium in the treatment of therapy-resistant depressive patients: a clinical, pharmacokinetic, and pharmacogenetic investigation Baumann, Pierre Nil, Rico Souche, Alain Montaldi, Stefano Baettig, Dominique Lambert, Susanne Uehlinger, Claude Kasas, Anton Amey, Marlyse Jonzier-Perey, Michèle info:eu-repo/semantics/article article 1996 Journal of Clinical Psychopharmacology, vol. 16, pp. 307-314 one$; TBOK eng oai:serval.unil.ch:BIB_4BA60F08CDFC 2022-05-07T01:17:24Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_4BA60F08CDFC Busulfan Pharmacokinetics in Adenosine Deaminase-Deficient Severe Combined Immunodeficiency Gene Therapy. info:doi:10.1016/j.bbmt.2020.07.004 info:eu-repo/semantics/altIdentifier/doi/10.1016/j.bbmt.2020.07.004 info:eu-repo/semantics/altIdentifier/pmid/32653625 Bradford, K.L. Liu, S. Krajinovic, M. Ansari, M. Garabedian, E. Tse, J. Wang, X. Shaw, K.L. Gaspar, H.B. Candotti, F. Kohn, D.B. info:eu-repo/semantics/article article 2020-10 Biology of blood and marrow transplantation, vol. 26, no. 10, pp. 1819-1827 info:eu-repo/semantics/altIdentifier/eissn/1523-6536 urn:issn:1083-8791 <![CDATA[The pharmacokinetics of low-dose busulfan (BU) were investigated as a nonmyeloablative conditioning regimen for autologous gene therapy (GT) in pediatric subjects with adenosine deaminase-deficient severe combined immunodeficiency disease (ADA SCID). In 3 successive clinical trials, which included either γ-retroviral (γ-RV) or lentiviral (LV) vectors, subjects were conditioned with BU using different dosing nomograms. The first cohort received BU doses based on body surface area (BSA), the second cohort received doses based on actual body weight (ABW), and in the third cohort, therapeutic drug monitoring (TDM) was used to target a specific area under the concentration-time curve (AUC). Neither BSA-based nor ABW-based dosing achieved a consistent cumulative BU AUC; in contrast, TDM-based dosing led to more consistent AUC. BU clearance increased as subject age increased from birth to 18 months. However, weight and age alone were insufficient to accurately predict the dose that would consistently achieve a target AUC. Furthermore, various clinical, laboratory, and genetic factors (eg, genotypes for glutathione-S-transferase isozymes known to participate in BU metabolism) were analyzed, but no single finding predicted subjects with rapid versus slow clearance. Analysis of BU AUC and the postengraftment vector copy number (VCN) in granulocytes, a surrogate marker of the level of engrafted gene-modified hematopoietic stem and progenitor cells (HSPCs), demonstrated gene marking at levels sufficient for therapeutic benefit in the subjects who had achieved the target BU AUC. Although many factors determine the ultimate engraftment following GT, this work demonstrates that the BU AUC correlated with the eventual level of engrafted gene-modified HSPCs within a vector group (γ-RV versus LV), with significantly higher levels of granulocyte VCN in the recipients of LV-modified grafts compared to recipients of γ-RV-transduced grafts. Taken together, these findings provide insight into low-dose BU pharmacokinetics in the unique setting of autologous GT for ADA SCID, and these dosing principles may be applied to future GT trials using low-dose BU to open the bone marrow niche

Time processing in visual cortices: How the visual brain encodes and keeps track of time

Time is embedded in any sensory experience: the movements of a dance, the rhythm of a piece of music, the words of a speaker are all examples of temporally structured sensory events. In humans, if and how visual cortices perform temporal processing remains unclear. Here we show that both primary visual cortex (V1) and extrastriate area V5/MT are causally involved in encoding and keeping time in memory and that this involvement is independent from low-level visual processing. Most importantly we demonstrate that V1 and V5/MT are functionally linked and temporally synchronized during time encoding whereas they are functionally independent and operate serially (V1 followed by V5/MT) while maintaining temporal information in working memory. These data challenge the traditional view of V1 and V5/MT as visuo-spatial features detectors and highlight the functional contribution and the temporal dynamics of these brain regions in the processing of time in millisecond range. The present project resulted in the paper entitled: 'How the visual brain encodes and keeps track of time' by Paolo Salvioni, Lysiann Kalmbach, Micah Murray and Domenica Bueti that is now submitted for publication to the Journal of Neuroscience

Neocortical Connectivity during Episodic Memory Formation

During the formation of new episodic memories, a rich array of perceptual information is bound together for long-term storage. However, the brain mechanisms by which sensory representations (such as colors, objects, or individuals) are selected for episodic encoding are currently unknown. We describe a functional magnetic resonance imaging experiment in which participants encoded the association between two classes of visual stimuli that elicit selective responses in the extrastriate visual cortex (faces and houses). Using connectivity analyses, we show that correlation in the hemodynamic signal between face- and place-sensitive voxels and the left dorsolateral prefrontal cortex is a reliable predictor of successful face–house binding. These data support the view that during episodic encoding, “top-down” control signals originating in the prefrontal cortex help determine which perceptual information is fated to be bound into the new episodic memory trace

The Complementary Brain: From Brain Dynamics To Conscious Experiences

How do our brains so effectively achieve adaptive behavior in a changing world? Evidence is reviewed that brains are organized into parallel processing streams with complementary properties. Hierarchical interactions within each stream and parallel interactions between streams create coherent behavioral representations that overcome the complementary deficiencies of each stream and support unitary conscious experiences. This perspective suggests how brain design reflects the organization of the physical world with which brains interact, and suggests an alternative to the computer metaphor suggesting that brains are organized into independent modules. Examples from perception, learning, cognition, and action are described, and theoretical concepts and mechanisms by which complementarity is accomplished are summarized.Defense Advanced Research Projects and the Office of Naval Research (N00014-95-1-0409); National Science Foundation (ITI-97-20333); Office of Naval Research (N00014-95-1-0657

The Complementary Brain: A Unifying View of Brain Specialization and Modularity

Defense Advanced Research Projects Agency and Office of Naval Research (N00014-95-I-0409); National Science Foundation (ITI-97-20333); Office of Naval Research (N00014-95-I-0657

The positional-specificity effect reveals a passive-trace contribution to visual short-term memory.

The positional-specificity effect refers to enhanced performance in visual short-term memory (VSTM) when the recognition probe is presented at the same location as had been the sample, even though location is irrelevant to the match/nonmatch decision. We investigated the mechanisms underlying this effect with behavioral and fMRI studies of object change-detection performance. To test whether the positional-specificity effect is a direct consequence of active storage in VSTM, we varied memory load, reasoning that it should be observed for all objects presented in a sub-span array of items. The results, however, indicated that although robust with a memory load of 1, the positional-specificity effect was restricted to the second of two sequentially presented sample stimuli in a load-of-2 experiment. An additional behavioral experiment showed that this disruption wasn't due to the increased load per se, because actively processing a second object--in the absence of a storage requirement--also eliminated the effect. These behavioral findings suggest that, during tests of object memory, position-related information is not actively stored in VSTM, but may be retained in a passive tag that marks the most recent site of selection. The fMRI data were consistent with this interpretation, failing to find location-specific bias in sustained delay-period activity, but revealing an enhanced response to recognition probes that matched the location of that trial's sample stimulus

Working memory in primate sensory systems

Sensory working memory consists of the short-term storage of sensory stimuli to guide behaviour. There is increasing evidence that elemental sensory dimensions — such as object motion in the visual system or the frequency of a sound in the auditory system — are stored by segregated feature-selective systems that include not only the prefrontal and parietal cortex, but also areas of sensory cortex that carry out relatively early stages of processing. These circuits seem to have a dual function: precise sensory encoding and short-term storage of this information. New results provide insights into how activity in these circuits represents the remembered sensory stimuli

Transcranial Magnetic Stimulation of Early Visual Cortex During Transsaccadic Integration of Object Features

Visual information is integrated across saccades to maintain a continuous spatiotemporal representation of the world. This study investigated the role of early visual cortex (EVC) in trans-saccadic integration using functional magnetic resonance imaging guided repetitive transcranial magnetic stimulation (rTMS) protocol. Triple-pulse rTMS was applied over left and right EVC during the fixation task (participants maintained gaze), and saccade task (participants made an eye movement that either maintained or reversed the visual quadrant of the test stimulus). rTMS had no effect when 1) fixation was maintained, 2) saccades kept the stimulus in the same visual quadrant, or 3) quadrant corresponding to the first Gabor patch was stimulated. However, rTMS affected performance (relative to opposite EVC rTMS) when saccades brought the remembered visual stimulus into the magnetically stimulated quadrant. This effect increased with saccade amplitude. These results show that EVC is involved in the memory and ‘remapping’ of visual features across saccades