Electrophysiological evidence for cognitive control during conflict processing in visual spatial attention

Event-related potentials were measured to investigate the role of visual spatial attention mechanisms in conflict processing. We suggested that a more difficult target selection leads to stronger attentional top-down control, thereby reducing the effects of arising conflicts. This hypothesis was tested by varying the selection difficulty in a location negative priming (NP) paradigm. The difficult task resulted in prolonged responses as compared to the easy task. A behavioral NP effect was only evident in the easy task. Psychophysiologically the easy task was associated with reduced parietal N1, enhanced frontocentral N2 and N2pc components and a prolonged P3 latency for the conflict as compared to the control condition. The N2pc effect was also obvious in the difficult task. Additionally frontocentral N2 amplitudes increased and latencies of N2pc and P3 were delayed compared to the easy task. The differences at frontocentral and parietal electrodes are consistent with previous studies ascribing activity in the prefrontal and parietal cortex as the source of top-down attentional control. Thus, we propose that stronger cognitive control is involved in the difficult task, resulting in a reduced behavioral NP conflict.     

Aberrant pattern of scanning in prosopagnosia reflects impaired face processing

Visual scanpath recording was used to investigate the information processing strategies used by a prosopagnosic patient, SC, when viewing faces. Compared to controls, SC showed an aberrant pattern of scanning, directing attention away from the internal configuration of facial features (eyes, nose) towards peripheral regions (hair, forehead) of the face. The results suggest that SC's face recognition deficit can be linked to an inability to assemble an accurate and unified face percept due to an abnormal allocation of attention away from the internal face region. Extraction of stimulus attributes necessary for face identity recognition is compromised by an aberrant face scanning pattern.     

Two routes to face perception: evidence from psychophysics and computational modeling

The aim of this study was to separately analyze the role of featural and configural face representations. Stimuli containing only featural information were created by cutting the faces into their parts and scrambling them. Stimuli only containing configural information were created by blurring the faces. Employing an old-new recognition task, the aim of Experiments 1 and 2 was to investigate whether unfamiliar faces (Exp. 1) or familiar faces (Exp. 2) can be recognized if only featural or configural information is provided. Both scrambled and blurred faces could be recognized above chance level. A further aim of Experiments 1 and 2 was to investigate whether our method of creating configural and featural stimuli is valid. Pre-activation of one form of representation did not facilitate recognition of the other, neither for unfamiliar faces (Exp. 1) nor for familiar faces (Exp. 2). This indicates a high internal validity of our method for creating configural and featural face stimuli. Experiment 3 examined whether features placed in their correct categorical relational position but with distorted metrical distances facilitated recognition of unfamiliar faces. These faces were recognized no better than the scrambled faces in Experiment 1, providing further evidence that facial features are stored independently of configural information. From these results we conclude that both featural and configural information are important to recognize a face and argue for a dual-mode hypothesis of face processing. Using the psychophysical results as motivation, we propose a computational framework that implements featural and configural processing routes using an appearance-based representation based on local features and their spatial relations. In three computational experiments (Experiments 4–6) using the same sets of stimuli, we show how this framework is able to model the psychophysical data.     

Neuroticism and psychopathy predict brain activation during moral and nonmoral emotion regulation

Functional neuroimaging has identified brain regions associated with voluntary regulation of emotion, including the prefrontal cortex and amygdala. The neural mechanisms underlying individual differences in emotion regulation have not been extensively studied. We investigated the neural correlates of neuroticism and psychopathic personality traits in the context of an emotion regulation task. Results showed that amygdala activity elicited by unpleasant pictures was positively correlated with neuroticism and negatively correlated with a specific psychopathic trait related to emotional underreactivity. During active attempts to decrease emotional responses to unpleasant pictures, superior and ventrolateral prefrontal activity was positively correlated with psychopathy, but not with neuroticism. In contrast, dorsolateral prefrontal activity was positively correlated with neuroticism, but not with psychopathy. Psychopathy was also negatively correlated with medial prefrontal activity in response to pictures depicting moral violations, suggesting reduced emotional responses to moral stimuli in individuals with high levels of psychopathic traits. These results demonstrate dissociable influences of different personality traits on neural activity associated with responses to emotional stimuli and on the recruitment of regulation-related brain activity during the active down-regulation of responses to negative emotional stimuli. These results have implications for the etiology of trait-based psychopathology involving emotional dysregulation.     

Associations of Maternal Prenatal Smoking with Early Childhood Physical Aggression,Hyperactivity-Impulsivity,and Their Co-Occurrence

This study investigated associations between maternal prenatal smoking and physical aggression (PA), hyperactivity-impulsivity (HI) and co-occurring PA and HI between ages 17 and 42 months in a population sample of children born in Québec (Canada) in 1997/1998 (N=1745). Trajectory model estimation showed three distinct developmental patterns for PA and four for HI. Multinomial regression analyses showed that prenatal smoking significantly predicted children’s likelihood to follow different PA trajectories beyond the effects of other perinatal factors, parental psychopathology, family functioning and parenting, and socio-economic factors. However, prenatal smoking was not a significant predictor of HI in a model with the same control variables. Further multinomial regression analyses showed that, together with gender, presence of siblings and maternal hostile reactive parenting, prenatal smoking independently predicted co-occurring high PA and high HI compared to low levels of both behaviors, to high PA alone, and to high HI alone. These results show that maternal prenatal smoking predicts multiple behavior regulation problems in early childhood.     

Habla Ingles? The Effects of Language Translation on Simulated Juror Decisions1

Two studies were conducted in which college students, acting as simulated jurors, heard the testimony of a defendant in an assault case. The testimony was presented in English or in another language (Spanish in Study 1 and Thai in Study 2) which was translated into English by an interpreter. In Study 1, non-Hispanics judged the defendant to be more guilty than did Hispanics when the defendant's testimony was presented in Spanish than when it was presented in English. This bias was offset when the judge's instructions admonished the jurors to ignore the fact that the defendant's testimony was translated. Similarly, in Study 2, subjects (all non-Thai) judged the defendent more guilty when his testimony was presented in Thai than when it was presented in English. Again, this bias was eliminated by the judge's instructions to the jurors to ignore the fact that the testimony was translated. The increased guilty verdicts for defendants who did not testify in English appeared to be due to prejudice and language ethnocentrism, the belief that defendants in U.S. courts should speak English.     

IMPLICIT MEMORY IN THE TACTILE MODALITY:

Abstract— Research on perceptual priming has previously focused exclusively on priming in the visual and auditory modalities. The present study explored whether perceptual priming also extends to the tactile modality. Tactile priming for Braille words was examined in a group of blind participants, using a Braille analogue of the stem-completion task. The results for tactile priming paralleled previous stem-completion results in other modalities. Manipulating the encoding task at study (semantic vs nonsemantic) dissociated implicit and explicit Braille stem-completion performance, and priming was unaffected by the number of study presentations (one vs three). Finally, Braille stem-completion priming was found in a cross-modal paradigm to have both a specifically tactile component and a cross-modal component. These results demonstrate for the first time that verbal priming can occur in the tactile domain and that tactile priming has basic functional similarities with stem-completion priming in the visual and auditory domains.     

The effect of increasing the memorability of category instances on estimates of category size

According to Tversky and Kahneman’s (1973) availability heuristic, people sometimes make use of the ease with which instances are retrieved when they have to estimate proportions or frequencies. One implication of this availability heuristic is that any factor that affects memorability of instances from a category should also affect the estimated category size. In one of their experiments, Tversky and Kahneman found that, after being presented with a list of names, people judged the more famous names to be more frequent. Similarly, recall was found to be greater for the more famous names. Three experiments that used Tversky and Kahneman’s paradigm are reported. Repeating nonfamous names resulted in their increased recallability and a corresponding increase in estimates of their frequency (Experiments 1 and 3). Making nonfamous names more salient (Experiment 3) also had parallel effects on recallability and frequency estimates, indicating that different memory manipulations affected availability in a similar fashion. Furthermore, reliance on the heuristic was not changed as a function of prior knowledge (Experiment 2) or practice (Experiment 3)