Spatial memory in the rat on a hierarchical maze

Rats were trained and tested on a hierarchical radial maze, which consisted of eight primary alleys radiating from a central platform and three secondary alleys which branched off the end of each primary alley. In four experiments, rats in groups 1, 2, and 3 were tested on maze configurations consisting of one, two, or three secondary alleys, respectively, at the end of each primary alley. In Experiment 1, each group was trained to collect food pellets in the secondary alleys. By the end of training, rats in each group collected all pellets efficiently, with little repetition of entrances into either primary or secondary alleys. In Experiments 2 and 3, tests were carried out which required retention of entrances into secondary alleys, as well as primary alleys. Two trials were run in succession, with selected secondary alleys blocked on trial 1 but open and baited with food on trial 2. Animals in groups 2 and 3 showed very accurate retention of blocked secondary alleys, regardless of variation in pattern and number of alleys blocked. A fourth experiment controlled for the possible use of food cues in Experiments 2 and 3 by rebaiting all secondary alleys between trials 1 and 2. Subjects continued to choose previously blocked alleys on trial 2, thus demonstrating that choice of blocked alleys was based on memory and not on a tendency to approach visual or olfactory food cues. Several findings of these experiments suggest that memories for primary and secondary alley choices are encoded and stored within separate memory systems. Possible coding mechanisms for these systems are discussed with reference to a process of cognitive mapping.     

Saccadic eye movements during reading

Exposure duration and sequential redundancy are major determinants of report accuracy for textual displays. Increased emission of left-to-right saccades to both word strings and letter strings are associated with sequential redundancy. Such saccades are more frequent when words rather than pseudowords are viewed. The pattern of scanning is not simply left to right, and certain patterns of eye movements are associated positively with accuracy of report. These are a function of the sequential constraints of the display and are stronger for word strings than for letter strings. Presence of a word elicits more left-to-right saccades than does a pseudoword, even at exposures too short for a second fixation to be useful. In that case, there is no difference between redundant and nonredundant pseudowords. There is no redundancy effect at short exposures of pseudosentences.     

Hemispheric functions in the processing of agent-patient information.

Left and right hemisphere processing capabilities for pictorial information about agent (performer of an action) and patient (recipient of an action) relations were assessed in a tachistoscopic study. Subjects were presented pictures in either the right or the left visual field depicting an agent-action-patient event. They were asked to locate which side of the drawing contained the agent and, in separate trials, which side contained the patient. Reaction times to locate the agent were significantly faster than to locate the patient, regardless of the field of presentation. The results are discussed in terms of a general nonlinguistic processing constraint that favors agent information. It is suggested that this processing asymmetry may underlie syntactic asymmetries regarding the expression of agents and patients in language.     

The role of vulnerable environments in support for homegrown terrorism: Fieldwork using the 3N model

The 3N model of radicalization proposes that violent radicalization is the result of the contribution of needs, networks, and narratives. Although research has mainly been supportive of this perspective, a substantial amount of ground remains uncovered regarding the network component of the model. Within this framework, we examine why individuals living in certain social environments tend to harbor more positive attitudes toward homegrown terrorism than others. Building on prior research, we hypothesized that individuals living in social environments known to be vulnerable (vs. less vulnerable) are more likely to experience a sense of significance loss (i.e., lack of social integration, perceived conflicts between religious groups), find solace in religious social networks (i.e., mosques), and thus adhere to radical narratives (i.e., legitimization of terrorism). A study with 365 young Muslims from different cities in Spain (Almería, Barcelona, Ceuta, and Melilla)supported these predictions. Theoretical and practical implications for the study of violent extremism are discussed.     

ERP correlates of attentional processing in spider fear: evidence of threat-specific hypervigilance

Attentional bias towards threat can be demonstrated by enhanced processing of threat-related targets and/or greater interference when threat-related distractors are present. These effects are argued to reflect processing within the orienting and executive control networks of the brain respectively. This study investigated behavioural (RT) and electrophysiological correlates of early selective attention and top-down attentional control among females with high (n?=?16) or low (n?=?16) spider fear (Mean age?=?22 years). Participants completed a novel flanker go/nogo task in which a central schematic flower or spider stimulus was flanked by either congruent or incongruent distractors. Participants responded to green stimuli (go trials) and withheld response to yellow stimuli (nogo trials). High fear participants demonstrated significantly shorter reaction times and greater P1 amplitude to spider targets, suggesting specific hypervigilance towards threat-relevant stimuli. In contrast to predictions, there was little evidence for behavioural interference effects or differences in N2 amplitude when distractor stimuli were threat-relevant.     

Trouble in Eden

In response to the Wild-Anderson Report, Little Children are Sacred (June 2007) that outlined a pattern of widespread sexual abuse of small children and chronic alcoholism among aboriginals in the Australians' N.T. (Northern Territory), the federal government launched a major Intervention there sending in teams of doctors and health workers to examine all aboriginal children for abuse and special police and army units to stabilise the situation in remote communities. Moving beyond the recommendations contained in the Report the Howard government announced it would use compulsory acquisition powers and appoint administrators over aboriginal townships and centres (about 73 of them) for five years. These officials would be charged with building up local infrastructures and could assign individuals to work for their welfare payments at jobs assigned to them. More disturbing to aboriginal leaders and communities was a government plan to allow individual aboriginals to lease small plots of land on traditional community owned reserves for the purpose, it was said, of owning their home and/or to start a small business. Furthermore, traditional owners would be allowed to enter into long term leases (for 99 years) on their lands in order to attract outside investment and capitol. There was considerable fear among aboriginals that these unilateral moves by the government would undermine the basis of aboriginal culture and lead inevitably to the loss by aboriginal people of real control over their traditional land.     

ERP Correlates of Effortful Control in Children with Varying Levels of ADHD Symptoms

As effortful control (EC), the self-regulation aspect of temperament, has been argued to play a key role in the normal and psychopathological course of development, research adding to the construct validity of EC is needed. In the current study, interrelations between the temperament construct of EC and the efficiency of the executive attention network, argued to underlie EC, were investigated, using event-related potentials (ERPs). In general, children scoring low on EC questionnaires made more errors of commission in the Go/No-Go task and showed smaller No-Go N2 or No-Go P3 amplitudes, two ERP components related to the executive attention network. The two EC scales (Effortful Control Scale and Attentional Control Scale), used in the current study, were differentially related to the outcome, indicating that they may measure different constructs. No-Go P3 amplitude was noted to be associated more strongly with EC than No-Go N2 amplitude. EC was found to be implicated in Attention-Deficit Hyperactivity Disorder (ADHD) symptomatology, as children scoring high on ADHD symptoms scored low on EC questionnaires, made more errors of commission, and showed smaller No-Go P3 amplitudes.     

Where has all the inhibition gone? Insights from electrophysiological measures into negative priming without probe distractors

Responses to probe targets that have been distractors in a prime display are slower than responses to unrepeated stimuli, a finding labeled negative priming (NP). However, without probe distractors the NP effect usually diminishes. The present study is the first to investigate ERP correlates of NP without probe distractors to shed light on the processes underlying NP. Based on existing findings in the field, we analyzed two ERP correlates that have been associated with the visual NP effect so far, namely the N200 and the P300. As expected, no behavioral NP effect as well as no N200 modulation emerged. However, the P300 component was enhanced when a prime distractor was repeated as the probe target. This effect is interpreted as reflecting automatic retrieval of the prime episode occurring independently of the presence of probe distractors.     

Brain correlates of early auditory processing are attenuated by expectations for time and pitch

The present study investigated how auditory processing is modulated by expectations for time and pitch by analyzing reaction times and event-related potentials (ERPs). In two experiments, tone sequences were presented to the participants, who had to discriminate whether the last tone of the sequence contained a short gap or was continuous (Experiment 1: go/nogo, Experiment 2: choice reaction). Expectations were induced by varying the temporal and pitch regularity of the sequence. Results were consistent across both experiments. Expectations for both time and pitch were associated with faster responding. Both temporal and pitch expectations led to an attenuation of the auditory N1, thus indicating a modulation of early, perceptual processing by temporal and pitch expectations. Effects of temporal expectations were also evident in a P300-like deflection, suggesting that temporal expectations also affect decision- or response-related processing stages.     

对乙肝患者群体认知的矛盾态度:行为与ERP证据

采用GNAT范式并结合事件相关电位（ERP）,考查不同矛盾状态（高矛盾VS低矛盾）被试对特殊群体的态度及其在行为、脑加工机制上的差异。结果表明：（1）个体对于乙肝患者存在矛盾态度;（2）高、低矛盾被试对乙肝患者的态度差异,主要表现在积极维度而非消极维度上。（3）N270的出现及LPC的差异表明,矛盾态度的加工是个体根据背景对预存性评价予以修正的过程。