measuring-subjective-value-risky-ambiguous-options-using-experimental

Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition ...

Cortical topography is one of the most fundamental organizing principles of cortical areas. One such topography - eccentricity mapping - is present even in high-order, ventral stream visual areas. Within these areas, different object categories have specific eccentricity biases. In particular, faces, letters and words appear to be associated with central visual-field bias, whereas buildings are associated with a peripheral one. We propose that resolution needs are an important factor in organizing object representations: objects whose recognition depends on analysis of fine detail will be associated with central-biased representations, whereas objects whose recognition entails large-scale integration will be more peripherally biased.

The topography of high-order human object areas.

Die Topographie der h&#xF6;herwertigen menschlichen Objekt Bereichen.

We have recently proposed a center-periphery organization based on resolution needs, in which objects engaging in recognition processes requiring central-vision (e.g., face-related) are associated with center-biased representations, while objects requiring large-scale feature integration (e.g., buildings) are associated with periphery-biased representations. Here we tested this hypothesis by comparing the center-periphery organization with activations to five object categories: faces, buildings, tools, letter strings, and words. We found that faces, letter strings, and words were mapped preferentially within the center-biased representation. Faces showed a hemispheric lateralization opposite to that of letter strings and words. In contrast, buildings were mapped mainly to the periphery-biased representation, while tools activated both central and peripheral representations. The results are compatible with the notion that center-periphery organization allows the optimal allocation of cortical magnification to the specific requirements of various recognition processes.

Eccentricity bias as an organizing principle for human high-order object areas.

Exzentrizit&#xE4;t Bias als organisierendes Prinzip f&#xFC;r den menschlichen h&#xF6;herwertigen Bereichen Objekt.

We have combined functional maps of retinotopy (eccentricity and meridian mapping), object category, and motion in a group of subjects to explore the large-scale topography of higher-order object areas. Our results reveal seven consistent category-related entities situated in the occipito-temporal cortex adjoining early visual areas. These include two face-related regions, three object-related regions, and two building-related regions. Interestingly, this complex category-related pattern is organized in a large-scale dorso-ventral mirror symmetry of object category. Furthermore, correlating this pattern to the map of visual field eccentricity, we found that the entire network of areas could be related to a single and unified eccentricity map. We hypothesize that this large-scale organization points to a possible development of high-order object areas through extension and specialization of a single proto-representation.

Large-scale mirror-symmetry organization of human occipito-temporal object areas.

Gro&#xDF;fl&#xE4;chige Spiegel-Symmetrie Organisation der menschlichen occipito-temporale Objekt Bereichen.

Recently we reported that the topographic organization of visual field eccentricity in human visual cortex extends into high-order, ventral occipitotemporal (VOT) cortex. Within this cortex, regions that respond preferentially to faces and buildings have specific eccentricity biases, suggesting that this category-eccentricity association may reflect differential needs of recognition processes. However, it is still not clear to what extent this center/periphery differentiation within high-order occipitotemporal cortex depends on immediate, moment-to-moment, task demands. Previous attention studies were confined either to exploring the visual field topography (spatial attention) or to object identity (object-based attention). Here, we combined the investigation of these two different attentional mechanisms in the same study. We found that the main source of attentional modulation in occipitotemporal cortex was object-based attention. Shifting attention to different object categories (buildings, faces, and arrows) substantially modulated the object-related activations. The differential activation to each object category in occipitotemporal object areas was maintained, albeit at a reduced level, even when attention was focused on different spatial locations. A slight eccentricity-related attentional differentiation was observed in the more dorsal lateral occipital region, but not in the VOT cortex. These results argue against the possibility that the source of the eccentricity differentiation in VOT cortex is due solely to moment-to-moment shifts in spatial attention mechanism and supports the notion that the eccentricity-biased maps found in this region are due to built-in shape selectivity established over long-term processes.

Spatial vs. object specific attention in high-order visual areas.

Vor kurzem berichteten wir, dass die topographische Organisation des Gesichtsfeldes Exzentrizit&auml;t in menschlichen visuellen Kortex auf h&ouml;herwertigen, ventral Occipitotemporal (VOT) Kortex erstreckt. Innerhalb dieser Kortex gibt es Regionen, die bevorzugt auf Fl&auml;chen und Geb&auml;ude zu reagieren bestimmte Exzentrizit&auml;t Vorurteile, darauf hindeutet, dass diese Kategorie-Exzentrizit&auml;t Zuordnung differenzielle Bed&uuml;rfnisse Erkennungsprozesse widerspiegeln kann. Es ist jedoch noch nicht klar, inwieweit dieses Zentrum/Peripherie-Differenzierung innerhalb der h&ouml;herwertigen Occipitotemporal Kortex sofort, von Moment zu Moment, Aufgabe Forderungen abh&auml;ngt. Fr&uuml;here Aufmerksamkeit Studien waren entweder zur Erforschung der visuellen Bereich Topografie (r&auml;umliche Aufmerksamkeit) oder Objektidentit&auml;t (objektbasierten Aufmerksamkeit) beschr&auml;nkt. Hier haben wir die Untersuchung dieser beiden unterschiedlichen syn&auml;sthetischen Mechanismen in der gleichen Studie kombiniert. Wir fanden, dass die Hauptquelle der syn&auml;sthetischen Modulation im Occipitotemporal Kortex objektbasierten Aufmerksamkeit. Verlagerung der Aufmerksamkeit auf verschiedenen Objektkategorien (Geb&auml;ude, Gesichter und Pfeile) wesentlich moduliert die objektbezogene Aktivierungen. Die differentielle Aktivierung jedes Objekt-Kategorie in Occipitotemporal Sachgebieten war, wenn auch mit verminderter, gepflegt auch wenn die Aufmerksamkeit auf verschiedene r&auml;umliche Standorte konzentriert war. Eine leichte Exzentrizit&auml;t-bezogene syn&auml;sthetischen Differenzierung wurde der Region mehr dorsalen seitlichen occipital, aber nicht in der Hirnrinde VOT beobachtet. Diese Ergebnisse argumentieren gegen die M&ouml;glichkeit, dass die Quelle der Exzentrizit&auml;t Unterscheidung im VOT Kortex ausschlie&szlig;lich auf die Moment-zu-Moment-Verschiebungen in r&auml;umliche Aufmerksamkeit Mechanismus zur&uuml;ckzuf&uuml;hren ist und unterst&uuml;tzt das Konzept, das die Exzentrizit&auml;t voreingenommen Karten gefunden in dieser Region aufgrund der integrierten Form Selektivit&auml;t errichteten &uuml;ber langfristige Prozesse sind.

R&auml;umliche vs. Objekt besondere Aufmerksamkeit in h&ouml;herwertigen visuellen Bereichen.

To what extent do all brains work alike during natural conditions? We explored this question by letting five subjects freely view half an hour of a popular movie while undergoing functional brain imaging. Applying an unbiased analysis in which spatiotemporal activity patterns in one brain were used to "model" activity in another brain, we found a striking level of voxel-by-voxel synchronization between individuals, not only in primary and secondary visual and auditory areas but also in association cortices. The results reveal a surprising tendency of individual brains to "tick collectively" during natural vision. The intersubject synchronization consisted of a widespread cortical activation pattern correlated with emotionally arousing scenes and regionally selective components. The characteristics of these activations were revealed with the use of an open-ended "reverse-correlation" approach, which inverts the conventional analysis by letting the brain signals themselves "pick up" the optimal stimuli for each specialized cortical area.

Intersubject synchronization of cortical activity during natural vision.

Interindividuelle Synchronisation der kortikalen Aktivit&#xE4;t w&#xE4;hrend nat&#xFC;rliches Sehen.

Several studies have shown that a region in the anterior collateral sulcus (CoS) and a region in the vicinity of the transverse occipital sulcus (TOS) are preferentially activated by images of buildings and scenes. We have found recently that these regions show a strong activation bias to stimuli located in the peripheral visual field. We explore in detail the source of this "periphery" effect. Our results show that the periphery effect can be generated by a large single object occupying the peripheral visual field as well as by multiple small peripheral objects. We also investigated whether the periphery effect was related to the annular shape used in conventional mapping of the visual field periphery and found that the mere presence of a stimulus in the visual field periphery, regardless of object shape, is sufficient to enhance activation. We also found that a small bias toward the peripheral visual field was shown even when the stimulated areas in the central and peripheral parts of the visual field are equated. Finally, our results demonstrate that the periphery effect shows object selectivity that can be obtained even with face images, which are the non-optimal stimulus for this region. In summary, our study shows that the building-related CoS and TOS manifest a true but graded retinotopic bias toward the peripheral visual field.

Functional analysis of the periphery effect in human building related areas.

Funktionelle Analyse der Peripherie Wirkung im menschlichen Geb&#xE4;udes verwandten Bereichen.

How many neurons participate in the representation of a single visual image? Answering this question is critical for constraining biologically inspired models of object recognition, which vary greatly in their assumptions from few "grandmother cells" to numerous neurons in widely distributed networks. Functional imaging techniques, such as fMRI, provide an opportunity to explore this issue, since they allow the simultaneous detection of the entire neuronal population responding to each stimulus. Several studies have shown that fMRI BOLD signal is approximately proportional to neuronal activity. However, since it provides an indirect measure of this activity, obtaining a realistic estimate of the number of activated neurons requires several intervening steps. Here, we used the extensive knowledge of primate V1 to yield a conservative estimate of the ratio between hemodynamic response and neuronal firing. This ratio was then used, in addition to several cautious assumptions, to assess the number of neurons responding to a single-object image in the entire visual cortex and particularly in object-related areas. Our results show that at least a million neurons in object-related cortex and about two hundred million neurons in the entire visual cortex are involved in the representation of a single-object image.

One picture is worth at least a million neurons.

Ein Bild sagt mehr mindestens eine Million Neuronen.

To what extent does the visual system's activity fluctuate when no sensory stimulation is present? Here, we studied this issue by examining spontaneous fluctuations in BOLD signal in the human visual system, while subjects were placed in complete darkness. Our results reveal widespread slow fluctuations during such rest periods. In contrast to stimulus-driven activity, during darkness, functionally distinct object areas were fluctuating in unison. These fMRI fluctuations became rapidly spatially de-correlated (39% drop in correlation level, P < 0.008) during visual stimulation. Functional connectivity analysis revealed that the slow spontaneous fluctuations during rest had consistent and specific neuro-anatomical distribution which argued against purely hemodynamic noise sources. Control experiments ruled out eye closure, low luminance and mental imagery as the underlying sources of the spontaneous fluctuations. These results demonstrate that, when no stimulus is present, sensory systems manifest a robust level of slow organized fluctuation patterns.

Widespread functional connectivity and fMRI fluctuations in human visual cortex in the absence of visual stimulation.

Inwieweit das visuelle schwanken System Aktivit&auml;t wenn keine sensorische Stimulation vorhanden ist? Hier studiert wir dieses Problem durch untersuchen spontane Fluktuationen in Fettschrift Signal in das menschliche visuelle System, w&auml;hrend Themen in v&ouml;lliger Dunkelheit platziert wurden. Unsere Ergebnisse zeigen weit verbreitete langsame Schwankungen w&auml;hrend solche Ruhezeiten. Im Gegensatz zu den Reiz-gesteuerte Aktivit&auml;t wurden w&auml;hrend der Dunkelheit, funktionell unterschiedlichen Sachgebieten Unisono schwankend. Diese fMRI-Schwankungen wurde rasch r&auml;umlich de-correlated (39 % R&uuml;ckgang der Korrelation Ebene P &lt; 0.008) w&auml;hrend visuelle Stimulation. Funktionelle Konnektivit&auml;t Analyse ergab, dass die langsamen spontanen Schwankungen w&auml;hrend der Rest hatte konsistent und spezifische Neuro-anatomische Verteilung das argumentierte gegen rein h&auml;modynamischen L&auml;rmquellen. Regelungs-Experimente ausgeschlossen Auge Schlie&szlig;ung, niedriger Intensit&auml;t und mentale Bilder als die zugrunde liegenden Quellen der spontanen Schwankungen. Diese Ergebnisse zeigen, dass, wenn kein Anreiz besteht, sensorischen Systeme ein robustes Ma&szlig; an langsam organisierte Fluktuation Muster manifestieren.

Weit verbreitete funktionelle Konnektivit&auml;t und fMRI Schwankungen menschlichen visuellen Kortex in Ermangelung der visuellen Stimulation.

Electrophysiological studies in monkeys have identified effector-related regions in the posterior parietal cortex (PPC). The lateral intraparietal area, for example, responds preferentially for saccades, whereas the parietal reach region responds preferentially for arm movements. However, the degree of effector selectivity actually observed is limited; each area contains neurons selective for the nonpreferred effector, and many neurons in both areas respond for both effectors. We used functional magnetic resonance imaging to assess the degree of effector preference at the population level, focusing on topographically organized regions in the human PPC [visual area V7, intraparietal sulcus 1 (IPS1), and IPS2]. An event-related design adapted from monkey experiments was used. In each trial, an effector cue preceded the appearance of a spatial target, after which a Go signal instructed subjects to produce the specified movement with the specified effector. Our results show that the degree of effector specificity is limited in many cortical areas and transitions gradually from saccade to reach preference as one moves through the hierarchy of areas in the occipital, parietal, and frontal cortices. Saccade preference was observed in visual cortex, including early areas and V7. IPS1 exhibited balanced activation to saccades and reaches, whereas IPS2 showed a weak but significant preference for reaches. In frontal cortex, areas near the central sulcus showed a clear and absolute preference for reaches, whereas the frontal eye field showed little or no effector selectivity. Although these results contradict many theoretical conclusions about effector specificity, they are compatible with the complex picture arising from electrophysiological studies and also with previous imaging studies that reported mostly overlapping saccade- and arm-related activation. The results are also compatible with theories of efficient coding in cortex.

Specificity of human cortical areas for reaches and saccades.

Elektrophysiologische Untersuchungen bei Affen haben Effektor-&auml;hnliche Regionen im hinteren parietalen Kortex (PPC) identifiziert. Beispielsweise reagiert die Lateralfl&auml;che intraparietal, bevorzugt f&uuml;r Sakkaden, w&auml;hrend der parietalen Region reagiert bevorzugt f&uuml;r Armbewegungen zu erreichen. Der Grad der Effektor-Selektivit&auml;t, die tats&auml;chlich zu beobachten ist jedoch begrenzt; Jeder Bereich enth&auml;lt Neuronen f&uuml;r die nonpreferred-Effektor selektive und viele Neuronen in beiden Bereichen f&uuml;r beide Effektoren zu antworten. Wir funktionelle Magnetresonanztomographie zum Effektor Pr&auml;ferenz auf Bev&ouml;lkerungsebene, pr&uuml;fen den Schwerpunkt auf topografisch organisierte Strukturen, die im menschlichen PPC verwendet [visuellen Bereich V7, intraparietal Sulcus 1 (IPS1), und IPS2]. Eine ereignisbezogene-Design angepasst von Affen-Experimenten wurde verwendet. In jeden Versuch voraus ein Effektor-Stichwort das Aussehen eines r&auml;umlichen Ziels, woraufhin ein Go-Signal, Themen angewiesen, die angegebene Bewegung mit den angegebenen Effektor zu produzieren. Unsere Ergebnisse zeigen, dass der Grad der Effektor Besonderheit in vielen kortikalen Bereichen und &Uuml;berg&auml;nge allm&auml;hlich von Saccade Pr&auml;ferenz als eine erreichen begrenzt bewegt sich durch die Hierarchie der Gebiete in den Cortices okzipitale, parietal und frontal. Saccade Pr&auml;ferenz wurde in der Sehrinde, einschlie&szlig;lich der fr&uuml;hen Bereiche und V7 beobachtet. IPS1 ausgestellt ausgewogenen Aktivierung Sakkaden und erreicht, w&auml;hrend die IPS2 zeigte eine schwache, aber signifikante Vorliebe f&uuml;r erreicht. Im frontalen Kortex nahe Bereiche der zentralen Sulcus zeigte eine klare und absolute Vorliebe f&uuml;r erreicht, w&auml;hrend Feld frontal Auge wenig oder gar keine Effektor-Selektivit&auml;t zeigte. Obwohl diese Ergebnisse viele theoretische Schl&uuml;sse &uuml;ber Effektor Spezifit&auml;t widersprechen, sind sie kompatibel mit dem komplexen Bild aus elektrophysiologische Untersuchungen und auch mit fr&uuml;heren Untersuchungen, die &uuml;berwiegend &uuml;berlappende Saccade - und Arm-bezogenen Aktivierung berichtet. Die Ergebnisse sind auch kompatibel mit den Theorien der effiziente Codierung in der Hirnrinde.

Besonderheit des menschlichen kortikalen Bereiche f&uuml;r erreicht und Sakkaden.

Fear learning is a rapid and persistent process that promotes defense against threats and reduces the need to relearn about danger. However, it is also important to flexibly readjust fear behavior when circumstances change. Indeed, a failure to adjust to changing conditions may contribute to anxiety disorders. A central, yet neglected aspect of fear modulation is the ability to flexibly shift fear responses from one stimulus to another if a once-threatening stimulus becomes safe or a once-safe stimulus becomes threatening. In these situations, the inhibition of fear and the development of fear reactions co-occur but are directed at different targets, requiring accurate responding under continuous stress. To date, research on fear modulation has focused mainly on the shift from fear to safety by using paradigms such as extinction, resulting in a reduction of fear. The aim of the present study was to track the dynamic shifts from fear to safety and from safety to fear when these transitions occur simultaneously. We used functional neuroimaging in conjunction with a fear-conditioning reversal paradigm. Our results reveal a unique dissociation within the ventromedial prefrontal cortex between a safe stimulus that previously predicted danger and a "naive" safe stimulus. We show that amygdala and striatal responses tracked the fear-predictive stimuli, flexibly flipping their responses from one predictive stimulus to another. Moreover, prediction errors associated with reversal learning correlated with striatal activation. These results elucidate how fear is readjusted to appropriately track environmental changes, and the brain mechanisms underlying the flexible control of fear.

From fear to safety and back: reversal of fear in the human brain.

Angst lernen ist eine rasche und anhaltende Prozess, der f&ouml;rdert die Abwehr von Bedrohungen und reduziert die Notwendigkeit von Gefahr, umlernen. Allerdings ist es auch wichtig, flexibel Angst Verhalten zu korrigieren, wenn Umst&auml;nde &auml;ndern. Tats&auml;chlich kann eine Verweigerung der Anpassung an ver&auml;nderte Bedingungen zu Angstst&ouml;rungen beitragen. Ein zentraler, aber vernachl&auml;ssigter Aspekt der Angst Modulation ist die F&auml;higkeit, flexibel Angst Antworten von einem Reiz auf einen anderen zu verschieben, wenn ein einmal-bedrohlichen Stimulus sicher wird oder ein einmal-sicher-Impuls wird bedroht. In diesen Situationen, die Hemmung der Angst und die Entwicklung der Angst Reaktionen Polarit&auml;tselement aber richten sich an verschiedene Ziele erfordern genaue Reaktion unter Dauerbelastung. Bis dato Forschung auf Angst hat Modulation haupts&auml;chlich auf die Verlagerung von Furcht zur Sicherheit konzentriert, mithilfe von Paradigmen wie Aussterben, was zu einer Verringerung der Angst. Ziel der vorliegenden Studie war, die dynamischen Schichten zu verfolgen, aus Angst um die Sicherheit und Sicherheit zu bef&uuml;rchten, wenn diese &Uuml;berg&auml;nge gleichzeitig auftreten. Wir verwendet funktionelle Neuroimaging in Verbindung mit einem Angst-Klimaanlage-Umkehr-Paradigma. Unsere Ergebnisse zeigen eine einzigartige Dissoziation innerhalb der ventromedialen pr&auml;frontalen Kortex zwischen sicher Ansporn, die zuvor Gefahr vorhergesagt und &quot;naiv&quot; sicher Ansporn. Wir zeigen, dass die Amygdala und Striatale Antworten die Angst-vorausschauende Reize nachverfolgt flexibel spiegeln ihre Antworten aus einer vorausschauenden Reiz zu einem anderen. Vorhersage-Fehlern zugeordnet au&szlig;erdem Umkehr lernen korrelierte mit Striatale Aktivierung. Diese Ergebnisse verdeutlichen, wie Angst angepasst ist, um entsprechend Umweltver&auml;nderungen und die Gehirn-Mechanismen die flexible Steuerung der Angst.

Von Angst zu Sicherheit und zur&uuml;ck: Umkehrung der Angst im menschlichen Gehirn.

Risk and ambiguity are two conditions in which the consequences of possible outcomes are not certain. Under risk, the probabilities of different outcomes can be estimated, whereas under ambiguity, even these probabilities are not known. Although most people exhibit at least some aversion to both risk and ambiguity, the degree of these aversions is largely uncorrelated across subjects, suggesting that risk aversion and ambiguity aversion are distinct phenomena. Previous studies have shown differences in brain activations for risky and ambiguous choices and have identified neural mechanisms that may mediate transitions from conditions of ambiguity to conditions of risk. Unknown, however, is whether the value of risky and ambiguous options is necessarily represented by two distinct systems or whether a common mechanism can be identified. To answer this question, we compared the neural representation of subjective value under risk and ambiguity. fMRI was used to track brain activation while subjects made choices regarding options that varied systematically in the amount of money offered and in either the probability of obtaining that amount or the level of ambiguity around that probability. A common system, consisting of at least the striatum and the medial prefrontal cortex, was found to represent subjective value under both conditions.

Neural representation of subjective value under risk and ambiguity.

Risiko und Mehrdeutigkeit sind zwei Bedingungen, in denen die Folgen m&ouml;glicher Ergebnisse nicht sicher sind. Unter Risiko k&ouml;nnen die Wahrscheinlichkeiten der verschiedenen Ergebnisse gesch&auml;tzt werden, w&auml;hrend unter unklaren, auch diese Wahrscheinlichkeiten nicht bekannt sind. Obwohl die meisten Menschen zumindest eine gewisse Abneigung gegen Risiken und Unklarheiten aufweisen, ist der Grad der diese Aversionen &uuml;ber Themen, die darauf hindeutet, dass die Risikoaversion und Mehrdeutigkeit Abneigung unterschiedliche Ph&auml;nomene sind weitgehend unkorreliert. Fr&uuml;here Studien zeigten Unterschiede in Hirnaktivierungen f&uuml;r riskant und mehrdeutige Entscheidungen und Neuronale Mechanismen, die &Uuml;berg&auml;nge von Bedingungen der Unklarheit zu Bedingungen des Risikos zu vermitteln, k&ouml;nnen identifiziert haben. Hingegen ist unbekannt, ob der Wert der riskanten und mehrdeutige Optionen unbedingt durch zwei unterschiedliche Systeme dargestellt wird oder ob ein gemeinsamer Mechanismus identifiziert werden kann. Um diese Frage zu beantworten, verglichen wir die neuronale Darstellung subjektiver Wert unter Risiko und Mehrdeutigkeit. fMRI wurde zur Gehirn-Aktivierung w&auml;hrend der Subjekte, die Entscheidungen &uuml;ber Optionen, die systematisch in der H&ouml;he von Geld variiert angeboten und in entweder die Wahrscheinlichkeit einer diesen Betrag oder auf der Ebene der Unklarheit um diese Wahrscheinlichkeit zu verfolgen. Ein gemeinsames System, bestehend aus mindestens Striatum und medialen pr&auml;frontalen Kortex, wurde festgestellt, dass subjektiven Wert unter beiden Bedingungen darstellen.

Neurale Darstellung subjektiver Wert unter Risiko und Mehrdeutigkeit.

Decision-making is often viewed as a two-stage process, where subjective values are first assigned to each option and then the option of the highest value is selected. Converging evidence suggests that these subjective values are represented in the striatum and medial prefrontal cortex (MPFC). A separate line of evidence suggests that activation in the same areas represents the values of rewards even when choice is not required, as in classical conditioning tasks. However, it is unclear whether the same neural mechanism is engaged in both cases. To address this question we measured brain activation with functional magnetic resonance imaging while human subjects passively viewed individual consumer goods. We then sampled activation from predefined regions of interest and used it to predict subsequent choices between the same items made outside of the scanner. Our results show that activation in the striatum and MPFC in the absence of choice predicts subsequent choices, suggesting that these brain areas represent value in a similar manner whether or not choice is required.

Choice from non-choice: predicting consumer preferences from blood oxygenation level-dependent signals obtained during passive viewing.

Entscheidungsfindung wird h&auml;ufig als ein zwei-Phasen-Prozess gesehen, wo subjektive Werte zun&auml;chst jede Option zugewiesen werden und dann die Option der h&ouml;chste Wert ausgew&auml;hlt ist. Konvergierende Anhaltspunkte daf&uuml;r, dass diese subjektive Werte im Striatum und medialen pr&auml;frontalen Kortex (MPFC) dargestellt werden. Eine separate Zeile der Beweis schl&auml;gt vor, dass die Aktivierung in den gleichen Bereichen stellt die Werte der Belohnungen, selbst wenn Wahl nicht erforderlich, wie klassische Konditionierung Aufgaben ist. Es ist jedoch unklar, ob der gleiche neuronale Mechanismus in beiden F&auml;llen t&auml;tig ist. Um diese Frage zu l&ouml;sen gemessen wir Gehirn Aktivierung mit Magnetresonanztomographie w&auml;hrend Versuchspersonen passiv einzelner Konsumg&uuml;ter angesehen. Dann abgetastet Aktivierung aus vordefinierten Regionen von Interesse und benutzte es, um vorherzusagen, nachfolgende Auswahlm&ouml;glichkeiten zwischen dieselben Elemente au&szlig;erhalb des Scanners. Unsere Ergebnisse zeigen, dass die Aktivierung im Striatum und MPFC in Ermangelung einer Rechtswahl nachfolgende Auswahlm&ouml;glichkeiten prognostiziert, was darauf hindeutet, dass diese Hirnareale Wert auf &auml;hnliche Weise darstellen, ob Wahl erforderlich ist.

Wahl von nicht-Wahl: Vorhersage von Verbraucherpr&auml;ferenzen aus Blut Sauerstoffversorgung Ebene-abh&auml;ngige Signale w&auml;hrend passive Anzeige erhalten.

Article	Year
The topography of high-order human object areas. Trends in cognitive sciences\| PubMed ID: 11912041	2002
Eccentricity bias as an organizing principle for human high-order object areas. Neuron\| PubMed ID: 11988177	2002
Large-scale mirror-symmetry organization of human occipito-temporal object areas. Neuron\| PubMed ID: 12670430	2003
Spatial vs. object specific attention in high-order visual areas. NeuroImage\| PubMed ID: 12814581	2003
Intersubject synchronization of cortical activity during natural vision. Science (New York, N.Y.)\| PubMed ID: 15016991	2004
Functional analysis of the periphery effect in human building related areas. Human brain mapping\| PubMed ID: 15083523	2004
One picture is worth at least a million neurons. Current biology : CB\| PubMed ID: 15182673	2004
Widespread functional connectivity and fMRI fluctuations in human visual cortex in the absence of visual stimulation. NeuroImage\| PubMed ID: 16413791	2006
Specificity of human cortical areas for reaches and saccades. The Journal of neuroscience : the official journal of the Society for Neuroscience\| PubMed ID: 17460081	2007
From fear to safety and back: reversal of fear in the human brain. The Journal of neuroscience : the official journal of the Society for Neuroscience\| PubMed ID: 18987188	2008
Neural representation of subjective value under risk and ambiguity. Journal of neurophysiology\| PubMed ID: 20032238	2010
Choice from non-choice: predicting consumer preferences from blood oxygenation level-dependent signals obtained during passive viewing. The Journal of neuroscience : the official journal of the Society for Neuroscience\| PubMed ID: 21209196	2011

Ifat Levy

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