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A growing literature posits attention as a core component of working memory (Baddeley, European Psychologist, 7(2), 85-97, 2002), yet research exploring this relationship is scarce in the temporal attention domain. The present research provided further evidence that the magnitude of the attentional blink (AB) can be influenced by working memory load (WML; Akyürek et al., Memory & Cognition 35, 621–627, 2007). Additionally, we behaviorally tested Akyürek and colleagues' (Psychophysiology, 47(6), 1134-1141, 2010) conclusion that working memory influences attention at an early stage by systematically manipulating the timing of the first target in relation to the stimuli preceding and following it. In two experiments, we demonstrated that the AB effect increases as the temporal interval between the first target and the stimulus following it decreases. Importantly, this effect was observed only when WML was low, indicating that WM influences attending to a second target at an early stage of attentional processing. [ABSTRACT FROM AUTHOR]

Abstract: Recent reviews have highlighted the important role that the posterior parietal cortex (PPC) serves during episodic memory retrieval. A handful of studies have also noted that the PPC is active when old information is present on tasks that do not require overt episodic retrieval. Based on this observation, we examined whether incidental study-phase retrieval, cued by the repeated presence of stimuli, was sufficient to activate the PPC and whether this activation would be modulated by the lag between the initial and repeated presentation of those stimuli. Blood flow was measured with positron emission tomography (PET) while subjects classified pictures that were either new, repeated following a short lag, or repeated following a long lag. Activity in the left inferior parietal lobule (IPL, BA 40), amongst other regions, was greater for repeated than new pictures, and was greater following a long lag than a short lag, even though intentional retrieval was not required. These results suggest that the presence of repeated stimuli is sufficient to initiate left PPC mediated episodic retrieval. [ABSTRACT FROM AUTHOR]

A number of neurobiological, psychological and social factors may account for cognitive impairment. In animal studies a relation between dental status and cognitive performance has been found. It is unclear whether such a relation exists for humans. In a first step we compared the performance of 1,351 participants (53% women, 47% men; age M = 54.0) with natural teeth to 487 edentulous participants (59% women, 41% men; age M = 71.3) on 12 cognitive tests. The natural teeth group had a lower mean age, fewer women, more years of education, higher mini-mental state (MMSE), and performed significantly higher on several cognitive tests. In a subsequent analysis, the cognitive performance of a subset of the participants (50–85 years) was examined. In this analysis, 211 had natural dentition and 188 were edentulous. The groups were matched for gender, age, social variables, diseases, stress and MMSE. The cognitive disadvantage of the edentulous group was still apparent. The results suggest that functional natural teeth relate to relatively preserved cognitive functioning in older age. [ABSTRACT FROM AUTHOR]

Studies of successful aging have typically defined elderly who fall in the upper end of a distribution of test scores as successful. A different definition of successful aging requires that older adults fall at or above the mean level of younger adults and maintain this level over time. Here we examined this definition of successful aging in a sample of 1463 individuals between the ages of 50 of 85. Based on principal coordinate analysis of cognitive and non-cognitive variables, we identified a group of 55 (8.3%) 70-85 years olds that were high functioning. This group of elderly showed elevated performance on a range of cognitive tasks. Non-cognitive factors that characterized this group included education and subjective health. The participants were retested 5 years later and the same type of analysis was repeated. Of the remaining individuals who initially were classified as high functioning, 18 (35%) remained high functioning and thus met the definition for successful aging. Years of education was a significant predictor of who remained successful over time. [ABSTRACT FROM AUTHOR]

Evidence from animal studies points to the importance of the parahippocampal region (PHR) [including entorhinal, perirhinal, and parahippocampal (PHC) cortices] for recognition of visual stimuli. Recent findings in animals suggest that PHR may also be involved in visual associative recognition memory for configurations of stimuli. Thus far, however, such involvement has not been demonstrated in humans. In fact, it has been argued that associative recognition in humans is critically dependent on the hippocampal formation (HF). To better understand the division of function between HF and PHR during recognition memory in humans, we measured the activity of both areas in healthy young adults during an associative recognition memory task using functional magnetic resonance imaging. To more precisely characterize the nature of the associations that might be coded by the HF and PHR during recognition, subjects were required to learn and were later tested for associations based on either the spatial arrangements of two stimuli or the identity of two stimuli (a face and a tool). An area in the PHC was found to be more active for recognized old configurations than new configurations in both the spatial and identity conditions. The HF, on the other hand, was more active for recognition of new configurations than old configurations and also more active in the spatial than the identity condition. These data highlight the involvement of PHR in the long-term coding of associative relationships between stimuli and help to clarify the nature of its functional distinction from the HF. [ABSTRACT FROM AUTHOR]

The hemispheric encoding/retrieval asymmetry (HERA) model is a process-specific description of experimental data provided by a large set of functional neuroimaging studies. According to HERA, left prefrontal cortex (PFC) is more involved than right PFC in episodic memory encoding, whereas right PFC is more involved than left PFC in episodic memory retrieval. Recently it has been claimed that this description does not hold for non-verbal materials. Here we propose a more precise formulation of HERA than previously, and argue that there is sufficient evidence to conclude that HERA, as reformulated, is true for both verbal and non-verbal materials. [Copyright &y& Elsevier]

Novelty discrimination refers to the ability to decide whether information is new or has been previously encountered. Recent functional neuroimaging work has demonstrated that the hippocampus plays an important function in novelty discrimination. In the study described here, we explored the idea that novelty discrimination does not depend on the hippocampus alone but involves large-scale functional neural networks consisting of spatially remote brain regions. We measured blood flow with positron emission tomography (PET) while subjects semantically encoded visually and auditorily presented situationally novel and familiar words. Following each PET scan, subjects’ memory was tested with a standard yes/no recognition test. Blood flow data were analyzed with the covariance-based seed partial least squares (PLS) method. Behaviorally, subjects’ recognition performance was higher for novel than familiar words. Neurally, two large-scale functional networks involving the same region of the hippocampus were identified which showed coherent activity either during the encoding of situationally novel (but not familiar) items or situationally familiar (but not novel) items. These findings indicate that different neural networks are active in the processing of situationally novel and familiar information. The observation that the hippocampus participates in both networks supports the principle of neural context. [Copyright &y& Elsevier]

A consistently reported finding in functional neuroimaging studies which compare processing of new information to processing of old information is a reduction in blood flow, and hence neural activity, associated with the old condition. This deactivation has been labeled neural priming. Some investigators have hypothesized that neural priming is the physiological mechanism underlying conceptual priming—a facilitation in the semantic processing of repeated information. Others, however, have hypothesized that neural priming reflects novelty assessment—a mechanism which minimizes the probability that redundant information will be stored in long‐term memory. In this paper, the conceptual priming and novelty assessment hypotheses are compared and contrasted in order to ask, and tentatively answer, the question: Are conceptual priming and novelty assessment cognitively and neurophysiologically distinct? Based on a review of the literature, it is suggested that whereas novelty assessment and conceptual priming are distinct cognitive entities, they cannot be presently separated neurophysiologically. That is, some novelty assessment deactivations may in fact reflect priming, and some priming deactivations may in fact reflect novelty assessment. [ABSTRACT FROM AUTHOR]

Addresses the issue of whether retrieval of event information is associated with activation of some of the brain regions that were engaged during encoding of this information. Principle of memory; Overlapping activations in auditory responsive cortex during encoding and retrieval of auditory information; Mean activity in auditory responsive cortex during visual word recognition.

Although previous behavioral studies have demonstrated that restudying already-learned items is mnemonically ineffective, the neural mechanisms underlying this phenomenon remain largely unknown. Here, functional magnetic resonance imaging (fMRI) was used to assess neural changes during a multi-trial associative learning task where participants repeatedly studied and were tested on unrelated English word pairs. The results revealed that the brain network involved in the initial encoding of the word pairs was less activated when participants restudied previously learned ones, supporting a pattern that we refer to as test-depressed encoding (TDE). More distinctively, the dorsal anterior cingulate cortex (dACC) showed greater activation when restudying learned vs. unlearned word pairs, suggesting dACC-mediated cognitive control of TDE. Functional connectivity analysis further consistently showed that the memory encoding network had a weakened neural coupling within itself, but an enhanced coupling with dACC under TDE. Together, the present work is the first to demonstrate that these dynamic modulations in regional activity and connectivity may reflect the neural foundation for TDE. [ABSTRACT FROM AUTHOR]

After an initial study of a set of items, an intervening test of those items results in superior final memory compared with restudying those items prior to the final test. This phenomenon has been termed the testing effect. The primary purpose of the present study was to juxtapose restudy and testing in order to assess, from an attention perspective, whether the re-encoding process occurring during testing (that contributes to a superior subsequent memory, i.e., testing effect) is different from the re-encoding process during the restudy. To this end, we adopted a concurrent task to divide attention during restudy and testing. In Experiment 1, we confirmed the mnemonic impairment of divided attention during both restudy and testing on the final test. In Experiment 2, we ruled out the confounding possibility of allocation of attention between the concurrent and memory tasks by finding that allocation of attention did not affect the impairment of divided attention on final test performance. Together, our data suggest that the re-encoding component of testing is similar to the re-encoding during restudy in terms of attentional demands. The consistency of our findings with other existing theoretical accounts of testing effect and one potential methodological difference amongst the reported studies in the literature that found mixed results were discussed. [ABSTRACT FROM AUTHOR]

Although multiple studies have demonstrated that the Implicit Association Test (IAT) can be successfully faked, a single study using the Implicit Relational Assessment Procedure (IRAP; McKenna, Barnes-Holmes, Barnes-Holmes, & Stewart, International Journal of Psychology and Psychological Therapy, 7(2): 253-268, ) concluded that this behavior-analytic alternative to implicit measures may be relatively immune to faking. The current study examined the fakability of the IRAP using more accessible faking instructions and an idiographic approach to stimulus selection. The methodology also provided an opportunity to examine split-half and test-retest reliability, an underreported statistic among existing IRAP publications. Three IRAPs were delivered in succession to 102 undergraduates randomly assigned to one of three conditions: three real IRAPs, two real IRAPs followed by a faked IRAP, or one real IRAP followed by two faked IRAPs. Split-half reliabilities were acceptable for four of the six real IRAPs and excellent for the three faked IRAPs. For the group receiving three real IRAPs, consecutive IRAPs generated significant test-retest correlations; the group engaging in two consecutive faked IRAPs also generated a significant test-retest correlation. Furthermore, all groups that received faking instructions subsequently demonstrated significantly reversed IRAP performance compared to previous real IRAPs and to real IRAPs in other conditions: Faking was robustly demonstrated. These results may have implications with regard not only to the fakability but also the reliability of the measure. Future research might focus on methods of detecting and/or preventing faking of the procedure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Neurological correlates of slot machine gambling were examined in pathological gamblers. [•] Differences in neurological activity were observed across slot outcome types (wins, losses) and win size (small, large). [•] Behavioral responses to outcomes of winning and losing were different across subjects. [•] Dopaminergic activation was related to win size. [Copyright &y& Elsevier]

"Mental time travel" refers to conscious experience of remembering the personal past and imagining the personal future. Little is known about its neural correlates. Here, using functional magnetic resonance imaging, we explored the hypothesis that mental time travel into "nonpresent" times (past and future) is enabled by a special conscious state (chronesthesia). Well-trained subjects repeatedly imagined taking one and the same short walk in a familiar environment, doing so either in the imagined past present, or future. In an additional condition, they recollected an instance in which they actually performed the same short walk in the same familiar setting. This design allowed us to measure brain activity correlated with "pure" conscious states of different moments of subjective time. The results showed that the left lateral parietal cortex was differentially activated by nonpresent subjective times compared with the present (past and future> present). A similar pattern was observed in the left frontal cortex, cerebellum, and thalamus. There was no evidence that the hippocampal region is involved in subjective time travel. These findings provide support for theoretical ideas concerning chronesthesia and mental time travel. [ABSTRACT FROM AUTHOR]

Abstract: A rapid response to environmental threat is highly adaptive and fearful facial expressions serve as important threat cues. The biological significance of these threat cues is demonstrated by neuroimaging findings of amygdala responses to backward masked fearful faces. Additionally, behavioral dot-probe studies reveal that backward masked fearful faces modulate spatial attention. However, little is known about the behavioral impact of the amygdala sensitivity to masked fearful faces. Using a dot-probe task with event-related functional magnetic resonance imaging (fMRI), we provide the first evidence that the amygdala is involved in orienting to backward masked fearful faces. Furthermore, this spatial attention-related amygdala response was correlated with activity in the anterior cingulate, superior temporal sulcus, and lingual gyrus. [Copyright &y& Elsevier]

Large-scale networks of brain regions are believed to mediate cognitive processes, including episodic memory. Analyses of regional differences in brain activity, measured by functional neuroimaging, have begun to identify putative components of these networks. To more fully characterize neurocognitive networks, however, it is necessary to use analytical methods that quantify neural network interactions. Here, we used positron emission tomography (PET) to measure brain activity during initial encoding and subsequent recognition of sentences and pictures. For each type of material, three recognition conditions were included which varied with respect to target density (0%, 50%, 100%). Analysis of large-scale activity patterns identified a collection of foci whose activity distinguished the processing of sentences vs. pictures. A second pattern, which showed strong prefrontal cortex involvement, distinguished the type of cognitive process (encoding or retrieval). For both pictures and sentences, the manipulation of target density was associated with minor activation changes. Instead, it was found to relate to systematic changes of functional connections between material-specific regions and several other brain regions, including medial temporal, right prefrontal and parietal regions. These findings provide evidence for large-scale neural interactions between material-specific and process-specific neural substrates of episodic encoding and retrieval. [ABSTRACT FROM AUTHOR]

Abstract: Prediction error (i.e., the difference between the expected and the actual event''s outcome) mediates adaptive behavior. Activity in the anterior mid-cingulate cortex (aMCC) and in the anterior insula (aINS) is associated with the commission of prediction errors under uncertainty. We propose a dynamic causal model of effective connectivity (i.e., neuronal coupling) between the aMCC, the aINS, and the striatum in which the task context drives activity in the aINS and the temporal prediction errors modulate extrinsic cingulate–insular connections. With functional magnetic resonance imaging, we scanned 15 participants when they performed a temporal prediction task. They observed visual animations and predicted when a stationary ball began moving after being contacted by another moving ball. To induced uncertainty-driven prediction errors, we introduced spatial gaps and temporal delays between the balls. Classical and Bayesian fMRI analyses provided evidence to support that the aMCC–aINS system along with the striatum not only responds when humans predict whether a dynamic event occurs but also when it occurs. Our results reveal that the insula is the entry port of a three-region pathway involved in the processing of temporal predictions. Moreover, prediction errors rather than attentional demands, task difficulty, or task duration exert an influence in the aMCC–aINS system. Prediction errors debilitate the effect of the aMCC on the aINS. Finally, our computational model provides a way forward to characterize the physiological parallel of temporal prediction errors elicited in dynamic tasks. [Copyright &y& Elsevier]

Abstract: An important aspect of the fear response is the allocation of spatial attention toward threatening stimuli. This response is so powerful that modulations in spatial attention can occur automatically without conscious awareness. Functional neuroimaging research suggests that the amygdala and anterior cingulate cortex (ACC) form a network involved in the rapid orienting of attention to threat. A hyper-responsive attention bias to threat is a common component of anxiety disorders. Yet, little is known of how individual differences in underlying brain morphometry relate to variability in attention bias to threat. Here, we performed two experiments using dot-probe tasks that measured individuals'' attention bias to backward masked fearful faces. We collected whole-brain structural magnetic resonance images and used voxel-based morphometry to measure brain morphometry. We tested the hypothesis that reduced gray matter within the amygdala and ACC would be associated with reduced attention bias to threat. In Experiment 1, we found that backward masked fearful faces captured spatial attention and that elevated attention bias to masked threat was associated with greater ACC gray matter volumes. In Experiment 2, this association was replicated in a separate sample. Thus, we provide initial and replicating evidence that ACC gray matter volume is correlated with biased attention to threat. Importantly, we demonstrate that variability in affective attention bias within the healthy population is associated with ACC morphometry. This result opens the door for future research into the underlying brain morphometry associated with attention bias in clinically anxious populations. [Copyright &y& Elsevier]

Spatial attention has been argued to be adaptive by enhancing the processing of visual stimuli within the ‘spotlight of attention’. We previously reported that crude threat cues (backward masked fearful faces) facilitate spatial attention through a network of brain regions consisting of the amygdala, anterior cingulate and contralateral visual cortex. However, results from previous functional magnetic resonance imaging (fMRI) dot-probe studies have been inconclusive regarding a fearful face-elicited contralateral modulation of visual targets. Here, we tested the hypothesis that the capture of spatial attention by crude threat cues would facilitate processing of subsequently presented visual stimuli within the masked fearful face-elicited ‘spotlight of attention’ in the contralateral visual cortex. Participants performed a backward masked fearful face dot-probe task while brain activity was measured with fMRI. Masked fearful face left visual field trials enhanced activity for spatially congruent targets in the right superior occipital gyrus, fusiform gyrus and lateral occipital complex, while masked fearful face right visual field trials enhanced activity in the left middle occipital gyrus. These data indicate that crude threat elicited spatial attention enhances the processing of subsequent visual stimuli in contralateral occipital cortex, which may occur by lowering neural activation thresholds in this retinotopic location. [ABSTRACT FROM PUBLISHER]

Abstract: Previous studies have shown that information that currently cannot be retrieved but will be retrieved on a subsequent, more supported task (i.e. is available but not accessible) has a distinct neural signature compared with non-available information. For verbal paired-associates, an availability signal has been revealed in left middle temporal cortex, an area potentially involved in the storage of such information, raising the possibility that availability signals are expressed in modality-specific storage sites. In the present study subjects encoded pictures and sounds representing concrete objects. One day later, during fMRI scanning, a verbal cued-recall task was administrated followed by a post-scan recognition task. Items remembered on both tasks were classified as accessible; items not remembered on the first but on the second task were classified as available; and items not remembered on any of the tasks were classified as not available. Multivariate partial-least-squares analyses revealed a modality-independent accessibility network with dominant contributions of left inferior parietal cortex, left inferior frontal cortex, and left hippocampus. Additionally, a modality-specific availability network was identified which included increased activity in visual regions for available pictorial information and in auditory regions for available sound information. These findings show that availability in memory, at least in part, is characterized by systematic changes in brain activity in sensory regions whereas memory access reflects differential activity in a modality-independent, conceptual network, thus indicating qualitative differences between availability and accessibility in memory. [Copyright &y& Elsevier]

This study investigated the potential for recreational gamblers to respond as if certain types of losing slot machine outcomes were actually closer to a win than others (termed the near-miss effect). Exposure to conditional discrimination training and testing disrupted this effect for 10 of the 16 participants. These 10 participants demonstrated high percentages of conditional discrimination testing performance, and the remaining 6 participants failed the discrimination tests. The implications for a verbally based behavioral explanation of gambling are presented. [ABSTRACT FROM AUTHOR]