The Role of Experienced Regret on Intertemporal Choice: An Experiment

Theoretical and empirical body of research have exposed the powerful role of experiencing regret in guiding choice behavior. In this paper, we examined the impact of experienced regret and rejoicing induced by feedback provided on a risk decision prior to a two-period intertemporal choice. To our knowledge, this is the first attempt to bring together experienced regret and choice over time. We used the two-component discounted utility model approach as a framework. We applied previous research findings on the effect of experienced regret on utility, and we performed an experiment to test whether experienced regret and rejoicing have an impact on the discount factor. We found that both experienced regret and rejoicing have an impact on the way people discount future: when regret is experienced the discount factor decreases, whereas when rejoicing is experienced the discount factor increases.intertemporal choice, regret theory

Priming of eye movements by masked stimuli

In a metacontrast paradigm I investigated how central symbolic and peripheral spatial primes influenced saccadic eye movements initiated by a target stimulus. Saccadic reaction times were a function of angular difference between movement directions indicated by prime and target (congruence). Saccades started earlier with high congruence than with low congruence (priming effect). In incongruent trials, gaze trajectories deviated away from the direction indicated by the prime (prime suppression). The priming effect and prime suppression increased with interstimulus interval between prime and mask. Response speed and congruence predicted the direction of gaze deviations. Gaze deviations towards or away from the prime seemed to reflect the relative timing between the onset of prime-suppression with respect to movement initiation. The effect of primes on saccadic reaction time and metrics were simulated in a neural network model based on the assumption that decision processes and response preparation both rely on population coding as their principle of neural representation. The model accounts for the reaction time data as well as for the observed gaze deviations.Wie beeinflussen maskierte Hinweisreize die Blickbewegungsreaktionen auf den nachfolgenden Zielreiz? In der vorliegenden Arbeit wurden zentral oder peripher dargebotene Hinweisreize mit der Metakontrasttechnik vom Zielreiz maskiert. Der Winkel zwischen der vom Hinweis- und der vom Zielreiz angezeigten Blickbewegungsrichtung (0 bis 180 Grad) sowie ihr zeitlicher Abstand (SOA 17 - 84 ms) wurden systematisch variiert. Die Aufgabe der Versuchspersonen bestand darin, so schnell und genau wie möglich einen Blicksprung vom zentralen Fixationspunt zu einem von acht kreisformig angeordneten Zielpunkten durchzuführen. Gemessen wurden der Beginn (Sakkadenstart) sowie der Verlauf eines Blicksprungs (Blickspuren). Sakkaden begannen um so früher, je geringer der Winkel zwischen der Hinweis- und dem Zielreizreizrichtung gewählt wurde (Priming-Effekt). Der Priming-Effekt vergrösserte sich linear mit dem SOA. Zeigten Hinweis und Zielreiz in unterschiedliche Richtungen (inkongruente Bedingungen), wichen die Blickspuren systematisch von der direkten Verbindungslinie zwischen dem Fixationspunkt und Zielposition ab. Abweichungen in oder entgegen die vom Hinweisreiz angezeigten Richtung konnten durch den Zeitpunkt des Sakkadenbeginns und die Kongruenz vorhergesagt werden: Relativ fröh auftretende Sakkaden zeigten Abweichungen in Richtung des Hinweisreizes, relativ späte Sakkaden wichen in die dem Hinweisreiz entgegengesetzte Richtung ab. Diese Abweichungen weisen auf eine durch den Hinweisreiz induzierte zeitliche Dynamik von Bahnung und Hemmung der Blickbewegungsrichtung hin. Das abschliessende Kapitel der Arbeit zeigt Simulationen dieser dynamischen Prozesse in einem neuronalen Netzwerk zur Blickbewegungssteuerung. Das Modell nimmt an, dass sowohl die Entscheidung, wann eine Sakkade gestartet wird, als auch ihr Verlauf durch Antwortvorbereitung in einer Gruppe von Neuronen basiert, welcher das Prinzip der Populationskodierung als Repräsentationsform von Blicksteuerung zugrunde liegt

adaptive strategies for reading with a forced retinal location

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Visual search without central vision – no single pseudofovea location is best

We typically fixate targets such that they are projected onto the fovea for best spatial resolution. Macular degeneration patients often develop fixation strategies such that targets are projected to an intact eccentric part of the retina, called pseudofovea. A longstanding debate concerns which pseudofovea-location is optimal for non-foveal vision. We examined how pseudofovea position and eccentricity affect performance in visual search, when vision is restricted to an off-foveal retinal region by a gaze-contingent display that dynamically blurs the stimulus except within a small viewing window (forced field location). Trained normally sighted participants were more accurate when forced field location was congruent with the required scan path direction; this contradicts the view that a single pseudofovea location is generally best. Rather, performance depends on the congruence between pseudofovea location and scan path direction

Differential Activity for Animals and Manipulable Objects in the Anterior Temporal Lobes

Neuropsychological evidence has highlighted the role of the anterior temporal lobes in the processing of conceptual knowledge. That putative role is only beginning to be investigated with fMRI as methodological advances are able to compensate for well-known susceptibility artifacts that affect the quality of the BOLD signal. In this article, we described differential BOLD activation for pictures of animals and manipulable objects in the anterior temporal lobes, consistent with previous neuropsychological findings. Furthermore, we found that the pattern of BOLD signal in the anterior temporal lobes is qualitatively different from that in the fusiform gyri. The latter regions are activated to different extents but always above baseline by images of the preferred and of the nonpreferred categories, whereas the anterior temporal lobes tend to be activated by images of the preferred category and deactivated (BOLD below baseline) by images of the nonpreferred category. In our experimental design, we also manipulated the decision that participants made over stimuli from the different semantic categories. We found that in the right temporal pole, the BOLD signal shows some evidence of being modulated by the task that participants were asked to perform, whereas BOLD activity in more posterior regions (e.g., the fusiform gyri) is not modulated by the task. These results reconcile the fMRI literature with the neuropsychological findings of deficits for animals after damage to the right temporal pole and suggest that anterior and posterior regions within the temporal lobes involved in object processing perform qualitatively different computations.Psycholog

Neural correlates of finger gnosis

Neuropsychological studies have described patients with a selective impairment of finger identification in association with posterior parietal lesions. However, evidence of the role of these areas in finger gnosis from studies of the healthy human brain is still scarce. Here we used functional magnetic resonance imaging to identify the brain network engaged in a novel finger gnosis task, the intermanual in-between task (IIBT), in healthy participants. Several brain regions exhibited a stronger blood oxygenation level-dependent (BOLD) response in IIBT than in a control task that did not explicitly rely on finger gnosis but used identical stimuli and motor responses as the IIBT. The IIBT involved stronger signal in the left inferior parietal lobule (IPL), bilateral precuneus (PCN), bilateral premotor cortex, and left inferior frontal gyrus. In all regions, stimulation of nonhomologous fingers of the two hands elicited higher BOLD signal than stimulation of homologous fingers. Only in the left anteromedial IPL (a-mIPL) and left PCN did signal strength decrease parametrically from nonhomology, through partial homology, to total homology with stimulation delivered synchronously to the two hands. With asynchronous stimulation, the signal was stronger in the left a-mIPL than in any other region, possibly indicating retention of task-relevant information. We suggest that the left PCN may contribute a supporting visuospatial representation via its functional connection to the right PCN. The a-mIPL may instead provide the core substrate of an explicit bilateral body structure representation for the fingers that when disrupted can produce the typical symptoms of finger agnosia

Spatiotopic updating across saccades revealed by spatially-specific fMRI adaptation

Brain representations of visual space are predominantly eye-centred (retinotopic) yet our experience of the world is largely world-centred (spatiotopic). A long-standing question is how the brain creates continuity between these reference frames across successive eye movements (saccades). Here we use functional magnetic resonance imaging (fMR.1) to address whether spatially specific repetition suppression (RS) is evident during trans-saccadic perception. We presented two successive Gabor patches (Si and S2) in either the upper or lower visual field, left or right of fixation. Spatial congruency was manipulated by having Si and S2 occur in the same or different upper/lower visual field. On half the trials, a saccade was cued between Si and S2, placing spatiotopic and retinotopic reference frames in opposition. Equivalent RS was observed in the posterior parietal cortex and frontal eye fields when Si-S2 were spatiotopically congruent, irrespective of whether retinotopic and spatiotopic coordinates were in accord or were placed in opposition by a saccade. Additionally the post-saccadic response to S2 demonstrated spatially-specific RS in retinotopic visual regions, with stronger RS in extrastriate than striate cortex. Collectively, these results are consistent with a robust trans-saccadic spatial updating mechanism for object position that directly influences even the earliest levels of visual processing

Individualizing Representational Similarity Analysis

Representational similarity analysis (RSA) is a popular multivariate analysis technique in cognitive neuroscience that uses functional neuroimaging to investigate the informational content encoded in brain activity. As RSA is increasingly being used to investigate more clinically-geared questions, the focus of such translational studies turns toward the importance of individual differences and their optimization within the experimental design. In this perspective, we focus on two design aspects: applying individual vs. averaged behavioral dissimilarity matrices to multiple participants' neuroimaging data and ensuring the congruency between tasks when measuring behavioral and neural representational spaces. Incorporating these methods permits the detection of individual differences in representational spaces and yields a better-defined transfer of information from representational spaces onto multivoxel patterns. Such design adaptations are prerequisites for optimal translation of RSA to the field of precision psychiatry

Temporal Signal-to-Noise Changes in Combined Multislice- and In-Plane-Accelerated Echo-Planar Imaging with a 20- and 64-Channel Coil

Echo-planar imaging (EPI) is the most common method of functional MRI for acquiring the blood oxygenation level-dependent (BOLD) contrast, allowing the acquisition of an entire brain volume within seconds. However, because imaging protocols are limited by hardware (e.g., fast gradient switching), researchers must compromise between spatial resolution, temporal resolution, or whole-brain coverage. Earlier attempts to circumvent this problem included developing protocols in which slices of a volume were acquired faster (i.e., in-plane acceleration (S)) or simultaneously (i.e., multislice acceleration (M)). However, applying acceleration methods can lead to a reduction in the temporal signal-to-noise ratio (tSNR): a critical measure of signal stability over time. Using a 20- and 64-channel receiver coil, we show that enabling S-acceleration consistently yielded a substantial decrease in tSNR, regardless of the receiver coil, whereas M-acceleration yielded less pronounced tSNR decrease. Moreover, tSNR losses tended to occur in temporal, insular, and medial brain regions and were more noticeable with the 20-channel coil, while with the 64-channel coil, the tSNR in lateral frontoparietal regions remained relatively stable up to six-fold M-acceleration producing comparable tSNR to that of no acceleration. Such methodological explorations can guide researchers and clinicians in optimizing imaging protocols depending on the brain regions under investigation

Linking Personality Traits to Individual Differences in Affective Spaces

Different individuals respond differently to emotional stimuli in their environment. Therefore, to understand how emotions are represented mentally will ultimately require investigations into individual-level information. Here we tasked participants with freely arranging emotionally charged images on a computer screen according to their subjective emotional similarity (yielding a unique affective space for each participant) and subsequently sought external validity of the layout of the individuals' affective spaces through the five-factor personality model (Neuroticism, Extraversion, Openness to Experience, Agreeableness, Conscientiousness) assessed via the NEO Five-Factor Inventory. Applying agglomerative hierarchical clustering to the group-level affective space revealed a set of underlying affective clusters whose within-cluster dissimilarity, per individual, was then correlated with individuals' personality scores. These cluster-based analyses predominantly revealed that the dispersion of the negative cluster showed a positive relationship with Neuroticism and a negative relationship with Conscientiousness, a finding that would be predicted by prior work. Such results demonstrate the non-spurious structure of individualized emotion information revealed by data-driven analyses of a behavioral task (and validated by incorporating psychological measures of personality) and corroborate prior knowledge of the interaction between affect and personality. Future investigations can similarly combine hypothesis- and data-driven methods to extend such findings, potentially yielding new perspectives on underlying cognitive processes, disease susceptibility, or even diagnostic/prognostic markers for mental disorders involving emotion dysregulation