Combining Trait Models of Impulsivity to Improve Explanation of Substance Use Behaviour

The UPPS‐P model of impulsivity is gaining popularity among personality and substance use researchers, but questions remain as to whether its five facets have incremental validity in explaining substance use over a more parsimonious model specifying only two facets: reward drive and rash impulsiveness. In three cross‐sectional studies (total N = 486), we investigated whether the novel components of the UPPS‐P model (negative Urgency, Premeditation, Perseverance, Sensation seeking, Positive urgency) predicted typical and problematic alcohol and cannabis use after accounting for reward drive, rash impulsiveness and trait neuroticism (assessed with the Eysenck Personality Questionnaire). Reward drive and rash impulsiveness scores were calculated using principal components analysis of multiple scales, including UPPS‐P premeditation and sensation seeking. Results showed that rash impulsiveness was a robust predictor of typical and problematic substance use. The novel facets of the UPPS‐P did not improve prediction of typical substance use. The urgency scales inconsistently predicted problematic use. Specifically, negative urgency predicted one of three measures of negative consequences from alcohol use, and positive urgency only predicted negative consequences from cannabis use. Results suggest that the three novel facets of the UPPS‐P model add little over a two component model in explaining substance use, although may provide preliminary evidence for the utility of a revised global urgency construct in explaining problematic substance use. Copyright © 2017 European Association of Personality Psychology     

Task Decomposition Through Competition in a Modular Connectionist Architecture: The What and Where Vision Tasks

A novel modular connectionist architecture is presented in which the networks composing the architecture compete to learn the training patterns. An outcome of the competition is that different networks learn different training patterns and, thus, learn to compute different functions. The architecture performs task decomposition in the sense that it learns to partition a task into two or more functionally independent tasks and allocates distinct networks to learn each task. In addition, the architecture tends to allocate to each task the network whose topology is most appropriate to that task. The architecture's performance on “what” and “where” vision tasks is presented and compared with the performance of two multilayer networks. Finally, it is noted that function decomposition is an underconstrained problem, and, thus, different modular architectures may decompose a function in different ways. A desirable decomposition can be achieved if the architecture is suitably restricted in the types of functions that it can compute. Finding appropriate restrictions is possible through the application of domain knowledge. A strength of the modular architecture is that its structure is well suited for incorporating domain knowledge.     

Repetition Priming Follows Spontaneous but not Prompted Recognition of Familiar Faces

Reaction times to make a familiarity decision to the faces of famous people were measured after recognition of the faces in a pre-training phase had occurred spontaneously or following prompting with a name or other cue. At test, reaction times to familiar faces that had been recognized spontaneously in the pre-training phase were significantly facilitated relative to an unprimed comparison condition. Reaction times to familiar faces recognized only after prompting in the pre-training phase were not significantly facilitated. This was demonstrated both when a name prompt was used (Experiments 1 and 3) and when subjects were cued with brief semantic information (Experiment 2).

Repetition priming was not found to depend on prior spontaneous recognition per se. In Experiment 3, spontaneously recognizing a familiar face did not prime subsequent familiarity judgements when the same face had only been identified following prompting on a prior encounter. In Experiment 4, recognition memory for faces recognized after cueing was found to be over 90% accurate. This indicates that prompted recognition does not yield repetition priming, even though subjects can remember the faces. A fusion of “face recognition unit” and “episodic record” accounts of the repetition priming effect may be more useful than either theory alone in explaining these results.     

Elemental and Configural Processes in Patterning Discrimination Learning

Three experiments used appetitive conditioning with rats to examine the involvement of elemental and configural processes in positive and negative patterning discriminations. The first experiment demonstrated that negative and, to some extent, positive patterning discriminations were learned more rapidly when these discriminations consisted of stimulus elements that had previously been the reinforced as opposed to the non-reinforced elements of a simple discrimination. Experiment 2 revealed an excitatory summation effect during the early phase of negative patterning learning that depended upon discrimination pretraining. The final experiment demonstrated faster discrimination learning between the compound and the less salient, rather than the more salient, element of an instrumental patterning task. The present set of results were interpreted as reflecting the possibility, consistent with connectionist theory, that internal representations of the conditioned stimuli change over the course of a patterning discrimination.     

The effects of post-encoding stress on recognition memory: examining the impact of skydiving in young men and women

Prior studies have indicated that post-encoding stress can protect memories from the effects of forgetting, and this has been taken as evidence that stress facilitates memory consolidation. However, it is not known whether stress acts by directly influencing the strength of the underlying memories or whether it influences the generation process that plays a critical role in tests such as free recall. To address this issue, we examined the effects of stress produced by skydiving on recognition memory for negative and neutral pictures. Relative to a non-stress control condition, post-encoding stress in males was found to increase recognition memory for neutral pictures. However, stress was not found to improve recognition for emotional pictures, nor was it found to influence recognition memory in female participants. Additional analysis of recognition performance suggested that stress increased familiarity-based recognition rather than recollection. This study indicates that stress can improve familiarity-based recognition, thus showing that stress directly increases the strength of the underlying memories.     

Anxiety reactivity and anxiety perseveration represent dissociable dimensions of trait anxiety

Trait anxiety is an individual-difference variable reflecting variation in state-anxiety elevations resulting from exposure to a stressor. It is usually measured using questionnaire instruments, such as the Spielberger State-Trait Anxiety Inventory (STAI-T). The present research conceptually distinguishes, and independently assesses, two hypothetical dimensions of anxiety vulnerability which, it is argued, could plausibly make independent contributions to variance in trait-anxiety scores. These dimensions are anxiety reactivity, the probability of experiencing an anxiety reaction to a stressor, and anxiety perseveration, the persistence of anxiety symptoms once elicited. Participants were asked three questions about each STAI-T item. The traditional STAI-T question assessed how much of the time this symptom was experienced; the anxiety-reactivity question assessed the probability of experiencing the symptom in response to a stressor; and the anxiety-perseveration question assessed how long the symptom persisted, if elicited. Regression analysis determined that anxiety reactivity and anxiety perseveration scores both accounted for independent variance in trait-anxiety scores. It is argued that models of anxiety vulnerability should seek to differentiate both the causes and the consequences of elevated anxiety reactivity and increased anxiety perseveration. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Recognition memory ROCs for item and associative information: The contribution of recollection and familiarity

Receiver-operating characteristics (ROCs) were examined in three recognition memory experiments. ROCs for item information (i.e., was this word presented?) were found to be curvilinear. However, ROCs for associative information (i.e., were these two words presented together?) were found to be linear. The results are in agreement with the predictions of a dual-process model that assumes that recognition judgments are -based on familiarity and recollection. Familiarity reflects the assessment of a continuous strength dimension and is well described as a signal detection process, whereas recollection reflects the retrieval of qualitative information about the study episode and behaves like a discrete threshold process. The results showed that memory judgments about items relied on a combination of recollection and familiarity, but that judgments about associations relied primarily on recollection. Further examination of the associative ROCs suggested that subjects were able to recollect that old pairs of items were in the study list, and, under some conditions, that new pairs were not in the study list.