Overgeneral memory extends to pictorial retrieval cues and correlates with cognitive features in posttraumatic stress disorder

Individuals with posttraumatic stress disorder (PTSD) show overgeneral memory (OGM) when retrieving autobiographical memories to word cues. We investigated whether OGM extends to picture cues and whether it is related to PTSD symptoms and cognitions. Trauma survivors with (n = 29) and without (n = 26) PTSD completed the standard Autobiographical Memory Test (AMT) and a novel picture version. Compared to the no-PTSD group, the PTSD group showed OGM in both test versions. Pictures facilitated specific memory retrieval, but this effect was no longer significant when verbal intelligence or depressive symptoms were controlled. OGM correlated with PTSD symptoms and perceived self-change; with intrusive memories, their perceived "nowness," responses to intrusions (thought suppression, rumination, dissociation), and negative interpretations of symptoms.     

Using dynamic field theory to rethink infant habituation

Much of what psychologists know about infant perception and cognition is based on habituation, but the process itself is still poorly understood. Here the authors offer a dynamic field model of infant visual habituation, which simulates the known features of habituation, including familiarity and novelty effects, stimulus intensity effects, and age and individual differences. The model is based on a general class of dynamic (time-based) models that integrate environmental input in varying metric dimensions to reach a single decision. Here the authors provide simulated visual input of varying strengths, distances, and durations to 2 coupled and interacting fields. The 1st represents the activation that drives "looking," and the 2nd, the inhibition that leads to "looking away," or habituation. By varying the parameters of the field, the authors simulate the time course of habituation trials and show how these dynamics can lead to different depths of habituation, which then determine how the system dishabituates. The authors use the model to simulate a set of influential experiments by R. Baillargeon (1986, 1987a, 1987b) using the well-known "drawbridge" paradigm. The dynamic field model provides a coherent explanation without invoking infant object knowledge. The authors show that small changes in model parameters can lead to qualitatively different outcomes. Because in typical infant cognition experiments, critical parameters are unknown, effects attributed to conceptual knowledge may be explained by the dynamics of habituation.     

Is prospective memory related to depression and anxiety? A hierarchical MPT modelling approach

Prospective memory (PM) refers to remembering to perform an action in the future. One hundred and twenty-nine students completed a laboratory event–based PM task as well as depression and anxiety questionnaires. The data were analysed with the beta-MPT version of the multinomial processing tree model of event-based PM. Thereby, the prospective and retrospective components of PM were estimated for each participant and were then correlated with depression and anxiety. State anxiety was negatively correlated with the prospective component of PM. Neither depression nor trait anxiety were related to either component of PM.     

Elevated disgust sensitivity in blood phobia

In order to demonstrate elevated disgust sensitivity and facilitated disgust learning in patients suffering from blood injection injury phobia, 23 phobics and 20 controls underwent an evaluative conditioning experiment. They were presented with picture pairs consisting of affectively neutral pictures (CS), which were followed by either disgust-inducing, fear-inducing, pleasant, or neutral scenes (US). During the presentation we recorded the electromyogram (EMG) of the musculus levator labii as a specific disgust indicator. Affective ratings for the pictures were determined before and after conditioning. Also, CS-US contingency verbalisation (CV) was assessed. Phobics reported a greater overall disgust sensitivity, experienced stronger feelings of disgust, and showed greater EMG responses while viewing disgust-eliciting scenes than control subjects. Evaluative conditioning occurred equally in both groups and depended on CV.     

Loneliness and social behaviours in a virtual social environment

Feeling lonely motivates people to reconnect with others, but it can also trigger a vicious cycle of cognitions and behaviours that reinforces their loneliness. In this study, we examined the behavioural consequences of loneliness in a virtual social environment. A total of 176 participants navigated a character (protagonist) through a two-dimensional browser game and rated the character's loneliness multiple times during the game. In the first part of the game, another character is introduced as the protagonist's spouse. At one point, the spouse leaves for an undetermined period of time but later returns. Immediately before this separation, higher ascribed loneliness of the protagonist was associated with more frequent interactions with the spouse. After the reunion, however, higher ascribed loneliness was associated with less frequent interactions with the spouse. Ascribed loneliness was not significantly related to the frequency of interactions with others nor to the frequency of solitary activities. These patterns held after controlling for ascribed positive affect. Participants' levels of loneliness were related to the level of ascribed loneliness only when the spouse was present but not when the spouse was absent. In sum, these findings suggest that the conditions that trigger the vicious cycle of loneliness are person- and situation-specific.     

Implications of Independent Versus Interdependent Self-knowledge for Motivated Social Cognition: The Semantic Procedural Interface Model of the Self

The Semantic Procedural Interface Model of the Self (SPI) suggests that, depending on the strength of the situational accessibility of independent or interdependent self-knowledge, people will tend to process stimuli either unaffected by context (context-independency) or cognizant of context (context-dependency). In this paper we describe the cognitive processes underlying context-independent or context-dependent information processing. We suggest that degree of context-dependency depends on cognitive control processes (attentional focus on focal or task-relevant information; inhibition of contextual or task-irrelevant information; task-management). Second, we predict motivational effects of the self's independence/interdependence by including assumptions about possible selves.     

Aging and Source Monitoring of Characters in Literary Texts

This research examines adult age differences in source monitoring for literary texts. Source monitoring refers to processes that lead to attributions regarding the source or origin of information (Johnson, Hashtroudi, & Lindsay, 1993). Young and older adults read a literary play (Experiment 1) or short story (Experiment 2). In a later source-monitoring test, participants decided whether statements originated from Character A, Character B, Character C, or none of them. Recognition memory for statements was lower for older adults. Age differences in source monitoring were also consistently observed in both experiments, suggesting that older adults are impaired in everyday source-monitoring tasks that involve written discourse.     

Using high frame rate CMOS sensors for three-dimensional eye tracking

A novel three-dimensional eye tracker is described and its performance evaluated. In contrast to previous devices based on conventional video standards, the present eye tracker is based on programmable CMOS image sensors, interfaced directly to digital processing circuitry to permit real-time image acquisition and processing. This architecture provides a number of important advantages, including image sampling rates of up to 400/sec measurement, direct pixel addressing for preprocessing and acquisition, and hard-disk storage of relevant image data. The reconfigurable digital processing circuitry also facilitatesin-line optimization of the front-end, time-critical processes. The primary acquisition algorithm for tracking the pupil and other eye features is designed around the generalized Hough transform. The tracker permits comprehensive measurement of eye movement (three degrees of freedom) and head movement (six degrees of freedom), and thus provides the basis for many types of vestibulo-oculomotor and visual research. The device has been qualified by the German Space Agency (DLR) and NASA for deployment on the International Space Station. It is foreseen that the device will be used together with appropriate stimulus generators as a general purpose facility for visual and vestibular experiments. Initial verification studies with an artificial eye demonstrate a measurement resolution of better than 0.1° in all three components (i.e., system noise for each of the components measured as 0.006° H, 0.005° V, and 0.016° T. Over a range of ±20° eye rotation, linearity was found to be <0.5% (H), <0.5% (V), and <2.0% (T). A comparison with the scierai search coil technique yieldednear equivalent values for the systemnoise and the thickness of Listing’s plane.