Compatibility between observed and executed finger movements: comparing symbolic, spatial, and imitative cues

Intuitively, one can assume that imitating a movement is an easier task than responding to a symbolic stimulus like a verbal instruction. Support for this suggestion can be found in neuropsychological research as well as in research on stimulus-response compatibility. However controlled experimental evidence for this assumption is still lacking. We used a stimulus-response compatibility paradigm to test the assumption. In a series of experiments, it was tested whether observed finger movements have a stronger influence on finger movement execution than a symbolic or spatial cue. In the first experiment, we compared symbolic cues with observed finger movements using an interference paradigm. Observing finger movements strongly influenced movement execution, irrespective of whether the finger movement was the relevant or the irrelevant stimulus dimension. In the second experiment, effects of observed finger movements and spatial finger cues were compared. The observed finger movement dominated the spatial finger cue. A reduction in the similarity of observed and executed action in the third experiment led to a decrease of the influence of observed finger movement, which demonstrates the crucial role of the imitative relation of observed and executed action for the described effects. The results are discussed in relation to recent models of stimulus-response compatibility. Neurocognitive support for the strong relationship between movement observation and movement execution is reported.     

Dimensional complexity and power spectral measures of the EEG during functional versus predicative problem solving

Electroencephalograms were recorded in 22 men while solving tasks of visual-pattern completion and during mental relaxation. They were primed (by foregoing trials) to solve these tasks either in a predicative or functional mode of thinking. Predicative thinking required that in order to complete the pattern the subject had to get involved with the logic of the static structure of the pattern and therefore had to recognize the recurrence of certain features of the elements (e.g., shape, color, and size). Functional thinking required involvement in a dynamic reading of the logic of the pattern and therefore to search for operations and actions to be performed on the pattern elements (e.g., pushing, mirroring, and rotating). The EEG complexity during predicative thinking decreased in comparison to functional thinking and mental relaxation, with this reduction being most pronounced over the right parietal cortex. A reduction in dimensional complexity during functional thinking as compared to mental relaxation, which was concentrated over the left central cortex, although significant, was less clear. The reduced EEG complexity during predicative thought, dominant over the right hemisphere, could reflect increased competitive inhibition among respective cortical neuron assemblies in association with the visual analysis of static element features, converging upon those predicates relevant for the solution.     

A neuro-cognitive visual system for object recognition based on testing of interactive attentional top-down hypotheses

We propose an extension of a systemic model for object recognition formulated by Rybak et al (1998 Vision Research 38 2387-2400) which is based on the functional organisation of the visual systems in primate brains. In contrast to the learning and recognition scheme of Rybak et al we do not assume a behavioural paradigm, i.e. a visuomotor programmed scanpath that determines the sequence of foveation on the different parts of the object. As in the basis architecture of Rybak et al, the system modules are separated into 'what'-like subsystems corresponding to the ventral occipito-inferotemporal visual path and 'where'-like complexes analogous to the dorsal occipito-parietal visual path. The 'what' system analyses local features in the actual foveation as in Rybak et al. But, in our case, the 'where' memory, instead of programming a behavioural scanpath, scores the spatial relationship between successive fixation and the spatial relationship between the associated main edges. The recognition is based on the identification of parts and their spatial relationship. This gives the learning and recognition mechanisms more flexibility in the sense that, for recognising an object, several different fixation sequences may be accepted.     

A direct method for multidimensional ratio scaling

A generalization of direct ratio scaling methods to multidimensional ratio scaling is described. This method requires an observer to report the proportion of a standard percept that is contained in a given percept and vice versa. The method was developed to meet requirements for experimentation in such areas as color vision, gustation, and olfaction.This investigation was supported by research grants from the Swedish Medical Research Council and the Wallenberg Foundation. The experimental work was carried out by Mr. G. Kylén.     

Causal attribution and hindsight bias for economic developments

Hindsight bias for economic developments was studied, with particular focus on the moderating effects of attitudes and causal attributions. Participants (N = 263) rated the likelihood of several economic developments 6 months before and 6 months after the euro introduction in 2002. Hindsight bias occurred selectively for attitude-consistent economic developments: Euro supporters showed stronger hindsight bias for positive developments than for negative ones; euro opponents showed the opposite pattern. Causal attribution further moderated the hindsight bias: participants who perceived a strong connection between the euro introduction and specific economic developments showed higher attitude-consistent hindsight bias than participants who perceived those developments as unrelated to the euro. It is argued that hindsight bias serves to stabilize subjective representations of the economy.     

One-sided nonparametric tests for ordinal data

Baumgartner, Weiss, and Schindler (1998) introduced a novel non-parametric test for the two-sample comparison that is superior to commonly used tests such as the Wilcoxon rank-sum test. A modification of the novel test statistic can be used for one-sided comparisons based on ordinal data. Such comparisons frequently occur in psychological research, and the Wilcoxon test is often recommended for their analysis. Here, the two tests were compared in a simulation study. According to this study the tests have a similar type I error rate, but the modified Baumgartner-Weiss-Schindler test is more powerful than the Wilcoxon test.     

Anchors distort estimates of expected duration

This research explored the effect of presenting participants an anchor, which is a salient standard of comparison, before asking them to estimate the amount of time they believe they will need to complete a task (expected duration estimation). Such anchors can be assumed to be common in real-life situations, e.g., duration suggestions made by work colleagues. Participants were 32 students (M age = 23.1 yr., SD = 3.2; 28 women) who received course credit for participating. In the presence or absence of one of two anchors they had to estimate how much time they would need to work on a catalogue task. Actual time needed for the task was also measured. As predicted, analysis showed that estimates of expected duration were distorted in the direction of the anchors, i.e., estimations were assimilated into the presented anchor value. The implications for time management are discussed.     

Rewarded remembering: dissociations between self-rated motivation and memory performance

People often claim that they perform better in memory performance tasks when they are more motivated. However, past research has shown minimal effects of motivation on memory performance when factors contributing to item-specific biases during encoding and retrieval are taken into account. The purpose of the present study was to examine the generality of this apparent dissociation by using more sensitive measures of experienced motivation and memory performance. Extrinsic motivation was manipulated through competition instructions, and subjective ratings of intrinsic and extrinsic motivation were obtained before and after study instructions. Participants studied a series of words, and memory performance was assessed by content recall (Experiment 1) and source recall (Experiment 2). Both experiments showed dissociation between subjective ratings of extrinsic motivation and actual memory performance, so that competition increased self-rated extrinsic motivation but had no effects on memory performance, including source recall. Inconsistent with most people's expectations, the findings suggest that extrinsic motivation has minimal effects on memory performance.     

Parenting, achievement strategies and satisfaction in ice hockey

The aim of this study is to understand adolescent players' satisfaction as a function of parenting styles, players' achievement strategies, and their norm breaking behavior. Finnish 14- and 16-year-old ice-hockey players (n=1018) completed a questionnaire measuring their achievement strategies (SAQ; Nurmi, Salmela--Aro & Haavisto, 1995 b), as well as scales of norm breaking and satisfaction, prepared for the present study. The parents (n=979) filled in scales measuring their parenting styles (CRPR; Pulkkinen, 1996) and attitudes towards norm breaking. Results revealed that players from authoritative families who showed a high level of mastery-orientation expressed high satisfaction in playing ice hockey. Results also showed negative associations between authoritative parenting and both task irrelevant and norm breaking behavior. Parents with parental stress and those with authoritarian parenting styles showed positive attitudes to norm breaking behavior, and players from authoritarian and parental stress homes showed norm breaking behavior in ice hockey. There was no association between norm breaking behavior and player satisfaction. Our results contribute to the planning of a coaching system that serves more educational and developmental purposes, and that encourages the desire to play ice hockey as a hobby.     

Rapid serial naming: relations between different stimuli and neuropsychological factors

We report two studies on rapid serial naming (RSN). Study 1 addressed the relations among RSN tasks comprising different stimuli. Separate components for RSN of alphanumeric and non-alphanumeric stimuli, as well as for tasks in which the stimuli alternated between categories were identified. In Study 2, phonological skills, processing speed, motor dexterity, and verbal fluency were found to explain RSN performance. The studies indicate: (1) that RSN tasks vary in their properties according to the stimuli used and according to the way the tasks are arranged, and (2) that RSN tasks are multi-componented.