Development of an instrument for measuring different types of cognitive load

According to cognitive load theory, instructions can impose three types of cognitive load on the learner: intrinsic load, extraneous load, and germane load. Proper measurement of the different types of cognitive load can help us understand why the effectiveness and efficiency of learning environments may differ as a function of instructional formats and learner characteristics. In this article, we present a ten-item instrument for the measurement of the three types of cognitive load. Principal component analysis on data from a lecture in statistics for PhD students (n = 56) in psychology and health sciences revealed a three-component solution, consistent with the types of load that the different items were intended to measure. This solution was confirmed by a confirmatory factor analysis of data from three lectures in statistics for different cohorts of bachelor students in the social and health sciences (ns = 171, 136, and 148), and received further support from a randomized experiment with university freshmen in the health sciences (n = 58).     

The influence of prior knowledge on the retrieval‐directed function of note taking in prior knowledge activation

Background. Prior knowledge activation facilitates learning. Note taking during prior knowledge activation (i.e., note taking directed at retrieving information from memory) might facilitate the activation process by enabling learners to build an external representation of their prior knowledge. However, taking notes might be less effective in supporting prior knowledge activation if available prior knowledge is limited. Aims. This study investigates the effects of the retrieval‐directed function of note taking depending on learners' level of prior knowledge. It is hypothesized that the effectiveness of note taking is influenced by the amount of prior knowledge learners already possess. Sample. Sixty‐one high school students participated in this study. A prior knowledge test was used to ascertain differences in level of prior knowledge and assign participants to a low or a high prior knowledge group. Method. A 2×2 factorial design was used to investigate the effects of note taking during prior knowledge activation (yes, no) depending on learners' level of prior knowledge (low, high) on mental effort, performance, and mental efficiency. Results. Note taking during prior knowledge activation lowered mental effort and increased mental efficiency for high prior knowledge learners. For low prior knowledge learners, note taking had the opposite effect on mental effort and mental efficiency. Conclusions. The effects of the retrieval‐directed function of note taking are influenced by learners' level of prior knowledge. Learners with high prior knowledge benefit from taking notes while activating prior knowledge, whereas note taking has no beneficial effects for learners with limited prior knowledge.     

Continuous visual control of interception

People generally try to keep their eyes on a moving target that they intend to catch or hit. In the present study we first examined how important it is to do so. We did this by designing two interception tasks that promote different eye movements. In both tasks it was important to be accurate relative to both the moving target and the static environment. We found that performance was more variable in relation to the structure that was not fixated. This suggests that the resolution of visual information that is gathered during the movement is important for continuously improving predictions about critical aspects of the task, such as anticipating where the target will be at some time in the future. If so, variability in performance should increase if the target briefly disappears from view just before being hit, even if the target moves completely predictably. We demonstrate that it does, indicating that new visual information is used to improve precision throughout the movement.     

Judgments of reachability are independent of visuomotor adaptation

The furthest distance that is judged to be reachable can change after participants have used a tool or if they are led to misjudge the position of their hand. Here we investigated how judged reachability changed when visual feedback about the hand was shifted. We hoped to distinguish between various ways in which visuomotor adaptation could influence judged reachability. Participants had to judge whether they could reach a virtual cube without actually doing so. They indicated whether they could reach this virtual cube by moving their hand. During these hand movements, visual feedback about the position of the hand was shifted in depth, either away from or toward the participant. Participants always adapted to the shifted feedback. In a session in which the hand movements in the presence of visual feedback were mainly in depth, perceived reachability shifted in accordance with the feedback (more distant cubes were judged to be reachable when feedback was shifted further away). In a second session in which the hand movements in the presence of visual feedback were mainly sideways, for some participants perceived reachability shifted in the opposite direction than we expected. The shift in perceived reachability was not correlated with the adaptation to the shift in visual feedback. We conclude that reachability judgments are not directly related to visuomotor adaptation.     

Timing the moment of impact in fast human movements

The reported resolution of timing the moment of impact in fast human movements differs widely depending on the task. Surprisingly, better timing is reported for the demanding task of batting a ball than for the much simpler task of tapping in synchrony with two hands. We wondered whether this is because a sizeable part of timing variability arises from misjudging the distance in the direction of one's own movement, so that moving faster (as the bat does when moving toward a ball) improves timing. We found that moving faster does indeed improve timing in both the above-mentioned tasks. After removing the proposed contribution of misjudging the distance in the direction of one's own movement, we estimated that the remaining standard deviation in timing is just over 6ms for both tasks.     

Beliefs about the social orientations of others: A parametric test of the triangle,false consensus,and cone hypotheses

This study tests a number of hypotheses proposed in the literature concerning the relationship between an actor's social orientation and her beliefs about the social orientations of others. In contrast to the existing literature, this study employs a parametric approach with an innovative methodology. First, the social orientation parameters of actors are estimated: the weights respondents add to (1) the outcomes of Alter and to (2) the absolute difference between the outcomes for Ego and Alter. Then, the mean and the variance of the distribution of beliefs about the social orientation parameters of others are estimated, conditional on the actor's social orientation parameters. The results show that (1) there is a positive association between an actor's social orientation and her belief about the mean of the social orientations of others and (2) those who have approximately zero social orientation parameter values (individualists) expect the variation of others' social orientations to be lower than those with smaller (competitors) or larger (cooperators/egalitarians) social orientation parameter values. These results support the cone model, which models the “false” consensus effect where the “false” consensus is highest for individualists.     

Retrieval-induced forgetting without competition: Testing the retrieval specificity assumption of the inhibition theory

According to the inhibition theory of forgetting (Anderson, Journal of Memory and Language 49:415–445, 2003; Anderson, Bjork, & Bjork, Psychonomic Bulletin & Review 7:522-530, 2000), retrieval practice on a subset of target items leads to forgetting for the other, nontarget items, due to the fact that these other items interfere during the retrieval process and have to be inhibited in order to resolve the interference. In this account, retrieval-induced forgetting occurs only when competition takes place between target and nontarget items during target item practice, since only in such a case is inhibition of the nontarget items necessary. Strengthening of the target item without active retrieval should not lead to such an impairment. In two experiments, we investigated this assumption by using noncompetitive retrieval during the practice phase. We strengthened the cue–target item association during practice by recall of the category name instead of the target item, and thus eliminated competition between the different item types (as in Anderson et al., Psychonomic Bulletin & Review 7:522-530 2000). In contrast to the expectations of the inhibition theory, retrieval-induced forgetting occurred even without competition, and thus the present study does not support the retrieval specificity assumption.     

Linear and nonlinear opponent color coding

The linearity axiom as proposed by Krantz (1975) is confirmed for red/green equilibria, i.e., lights which appear neither reddish nor greenish (unique yellows, unique blues, and achromatic colors). This experiment also gave some evidence of “veiling,” i.e., the masking of a weak hue component by a strong one. In a second experiment, hue magnitude estimates (HME) for the green component were obtained in variable mixtures of unique green and unique yellow stimuli. Contrary to the suggestion raised by the work of Yager and Taylor (1970), we did not find the relation between the HME and the luminance of the green stimulus to be independent of the amount of added yellow. A relation proposed by Indow and Stevens (1966), in which the proportion of the green luminance is taken as the relevant psychophysical unit, gives a better fit to our data. It is shown, however, that alternative interpretations of such data are possible and that this type of experiment cannot be conclusive regarding the issue of the possibility of absolute judgment of opponent hue attributes.

     

The effect of expectation on the identification of known and unknown persons

In this experiment we investigated the influence of expectation, exposure time and jacket hood positioning on person identification. Thirty subjects, all employees of the TNO Institute for Perception, participated in the experiment. They were presented with slides showing known and unknown persons who were photographed under bad lighting conditions. Limited viewing conditions considerably deteriorated subjects' performance and under these circumstances all experimental manipulations significantly affected identification accuracy. Contrary to what was expected longer exposure times impaired performance. The results are discussed in light of recent research on face recognition (Bruce and Young, 1986; Read, Vokey, and Hammersley, 1990).     

Holding an object one is looking at: Kinesthetic information on the object’s distance does not improve visual judgments of its size

Visual judgments of distance are often inaccurate. Nevertheless, information on distance must be procured if retinal image size is to be used to judge an object’s dimensions. In the present study, we examined whether kinesthetic information about an object’s distance—based on the posture of the arm and hand when holding it—influences the object’s perceived size. Subjects were presented with a computer simulation of a cube. This cube’s position was coupled to that of a rod in the subject’s hand. Its size was varied between presentations. Subjects had to judge whether the cube they saw was larger than, smaller than, or the same size as a reference. On some presentations, a small difference was introduced between the positions of the rod and of the simulated cube. When the simulated cube was slightly closer than the rod, subjects judged the cube to be larger. When it was farther away, they judged it to be smaller. We show that these changes in perceived size are due to alterations in the cube’s distance from the subject rather than to kinesthetic information.