Rated age-of-acquisition norms for over 3,200 German words

Words that have been learned early in life are responded to faster than words that have been acquired later. Subjective ratings of acquisition ages have been successfully employed to study the effect of age of acquisition (AoA). Although a large number of norms exist in many languages, fewer are available for German. Therefore, subjective AoA ratings for 3,259 German words were collected online, including 2,363 nouns and 473 verbs. These words were presented in lists of 140 words, and participants rated the age in years at which they had first learned each word. A split-half correlation testified to a high internal reliability. There were also high correlations with rated AoA values for subsets of the items that had been collected in previous studies, in both German and English. Age and gender were found to influence the ratings very weakly, in that older and male participants tended to give slightly higher age ratings. Education, multilingualism, and frequent usage of languages other than German did not exert an influence on the rating values. These new ratings will extend the currently existing norms available for language and reading research across languages and will provide researchers with a wider choice of word stimuli. The ratings are available expressed in two measurements: age in years, and AoA rated on a 7-point Likert scale.     

Inferred threat and safety: Symbolic generalization of human avoidance learning

Symbolic generalization of avoidance may underlie the aetiology and maintenance of anxiety disorders. The aim of the present study was to demonstrate inferred threat-avoidance and safety (non-avoidance) behaviours that occur in the presence of stimuli indirectly related to learned threat and safety cues. A laboratory experiment was conducted involving two symbolic stimulus equivalence relations consisting of three physically dissimilar stimuli (avoidance cues: AV1–AV2–AV3 and neutral cues: N1–N2–N3). During avoidance learning involving aversive images and sounds, a key-press avoidance response was trained for one member of one of the relations (AV2) and non-avoidance for another (N2). Inferred threat and safety behaviour and ratings of the likelihood of aversive events were tested with presentations of all remaining stimuli. Findings showed a significantly high percentage of avoidance to both the learned and inferred threat cues and less avoidance to both the learned and inferred safety cues. Ratings in the absence of avoidance were high during training and testing to threat cues and low to safety cues and were generally lower in the presence of avoidance. Implications for associative and behavioural accounts of avoidance, and modern therapies for anxiety disorders are discussed.     

Estimating the growth of internal evidence guiding perceptual decisions

Perceptual decision-making is thought to involve a gradual accrual of noisy evidence. Temporal integration of the evidence reduces the relative contribution of dynamic internal noise to the decision variable, thereby boosting its signal-to-noise ratio. We aimed to estimate the internal evidence guiding perceptual decisions over time, using a novel combination of external noise and the response signal methods. Observers performed orientation discrimination of patterns presented in external noise. We varied the contrast of the patterns and the delay at which observers were forced to signal their decision. Each test stimulus (patterns and noise sample) was presented twice. Across two experiments we varied the availability of the visual stimulus for processing. Observer model analyses of discrimination accuracy and response consistency to two passes of the same stimulus, suggested that there was very little growth in the internal evidence. The improvement in accuracy over time characterised by the speed-accuracy trade-off function predominantly reflected a decreasing proportion of non-visual decisions, or pure guesses. There was no advantage to having the visual patterns visible for longer than 80 ms, indicating that only the visual information in a short window after display onset was used to drive the decisions. The remarkable constancy of the internal evidence over time suggests that temporal integration of the sensory information was very limited. Alternatively, more extended integration of the evidence from memory could have taken place, provided that the dominant source of internal noise limiting performance occurs between-trials, which cannot be reduced by prolonged evidence integration.     

Affective bias in complex decision making: Modulating sensitivity to aversive feedback

The present study investigated the conflict between well-developed attitudes and incentive rewards using the Iowa Gambling Task. In particular, the incorporation of emotional labels allowed us to model the role of affective biases and their impact on complex decision making over time. Two experiments manipulated the class of deck label (emotional pictures and racial faces) using both congruent and incongruent association to the deck incentives. Both experiments demonstrated that an incongruent association can lead to striking and persistent decision making biases. Thus, a common theme was a general inability to tolerate conflict between rewards and goal-irrelevant labels. Notably, Experiment 2 demonstrated that this ‘incongruency’ effect appeared to result from positive labels interfering with aversive experiences from bad decks. More generally, sensitivity to accumulating losses from punishing decks was primarily associated with successful performance on these Gambling Task variants. These results suggest emotional biases are readily harmful in complex decision making, and that flexibility in the extent to which we permit emotional influences to guide our decisions is crucial.     

Touching my left elbow: the anatomical structure of the body affects the illusion of self-touch

A self-touch paradigm is used to create the illusion that one is touching one's own left elbow when one is actually touching the examiner's arm. Our new self-touch illusion is sensitive to the anatomical structure of the body: you can touch your left elbow with your right index finger but not with your left index finger. Illusion onset was faster and illusion ratings were higher when participants administered touch using the plausible right index finger compared with the implausible left index finger.     

Something Overlooked? How experts in change detection use visual saliency

How does expertise in the analysis of particular images influence the effects of visual saliency upon attention? Expert analysts of aerial photographs and untrained viewers undertook change‐detection and location memory tasks using aerial photographs with eye movements recorded throughout. Experts were more accurate in both tasks. Significant differences were also seen in the scanpaths: Untrained viewers fixated preferentially upon salient features throughout stimulus presentation whereas experts did not. However, both groups showed a strong influence of saliency in change detection and memory tasks. We interpret this apparent contradiction by: (i) assuming that the use of saliency in visual search is discretionary, and experts can use semantic information to prioritise where to fixate next; whereas, (ii) in tasks requiring spatial memory, analysis of visual saliency delivers easily acquired landmarks to reference the location of items in an image; a previously overlooked function used by expert and untrained viewers alike. Copyright © 2009 John Wiley & Sons, Ltd.     

Tactile expectations and the perception of self-touch: An investigation using the rubber hand paradigm

The rubber hand paradigm is used to create the illusion of self-touch, by having the participant administer stimulation to a prosthetic hand while the Examiner, with an identical stimulus (index finger, paintbrush or stick), administers stimulation to the participant’s hand. With synchronous stimulation, participants experience the compelling illusion that they are touching their own hand. In the current study, the robustness of this illusion was assessed using incongruent stimuli. The participant used the index finger of the right hand to administer stimulation to a prosthetic hand while the Examiner used a paintbrush to administer stimulation to the participant’s left hand. The results indicate that this violation of tactile expectations does not diminish the illusion of self-touch. Participants experienced the illusion despite the use of incongruent stimuli, both when vision was precluded and when visual feedback provided clear evidence of the tactile mismatch.     

Irrational beliefs and unconditional self-acceptance. I. Correlational evidence linking two key features of REBT

In a study with 102 non-clinical adults, relationships between measures of irrational beliefs, unconditional self-acceptance, self-esteem and the Big-5 personality dimensions were investigated. As expected, unconditional self-acceptance was highly correlated with self-esteem. In line with key tenets of REBT, individuals who scored highly on unconditional self-acceptance scored low on irrational beliefs even after self-esteem had been partialled out. Unconditional self-acceptance was found to be significantly (negatively) correlated with Neuroticism but not with other Big-5 personality dimensions. Irrational beliefs were found to correlate positively with Neuroticism and negatively with Openness. Factor analysis of the unconditional self-acceptance scale did not show a simple one-dimensional structure. A revised version of the scale comprising those items that did not load on a self-esteem factor produced a purer measure of unconditional self-acceptance that did not correlate significantly with self-esteem. The findings have implications for investigating unconditional self-acceptance in studies of therapeutic outcome.