Perceptual effect on motor learning in the serial reaction-time task

Although the Serial Reaction-Time Task has been an effective tool in studying procedural learning, there is still a debate as to whether learning in the task is effector-based, stimulus-based, or response-based. In this article, the authors contribute to this debate by contrasting response- and stimulus-based learning by manipulating them selectively and simultaneously. Results show that (a) participants learned response sequences in the absence of stimulus-specific perceptual sequence information but (b) not stimulus sequences without corresponding response information. In a third condition, response sequence and stimulus frequency information were in conflict, and each effect decreased learning in the other domain. Overall, our findings show that learning in these tasks is primarily motor-based, but it is also constrained by relatively salient perceptual information. Together with earlier findings in the literature, the findings also suggest a task and stimulus-arrangement-specific interaction between motor and perceptual learning, where relevance and salience of the specific information plays a crucial role.     

The effect of a non-informative cueing signal in a three-choice reaction-time task

Summary Many studies have shown that in a simple reaction-time (RT) task a non-informative leading cue decreases RT to a subsequent target presented in the same region as the cue. This facilitation lasts about 150 ms; it is then replaced by a sustained inhibition. Experiment 1 tests the hypothesis that the initial facilitation is due to motor, rather than perceptual, processes by using choice RT. Facilitation is greater and lasts longer in choice than in simple tasks, thus supporting the hypothesis. Experiment 2 shows that facilitation occurs even when the subject actively orients his or her attention away from the cue.     

The moderating effect of motivation on health-related decision-making

Objective: This study identifies how autonomous and controlled motivation moderates the cognitive process that drives the adoption of personalised nutrition services. The cognitive process comprises perceptions of privacy risk, personalisation benefit, and their determinants.

Design: Depending on their level of autonomous and controlled motivation, participants (N = 3453) were assigned to one of four motivational orientations, which resulted in a 2 (low/high autonomous motivation) × 2 (low/high controlled motivation) quasi-experimental design.

Results: High levels of autonomous motivation strengthened the extent to which: (1) the benefits of engaging with a service determined the outcome of a risk-benefit trade-off; (2) the effectiveness of a service determined benefit perceptions. High levels of controlled motivation influenced the extent to which: (1) the risk of privacy loss determined the outcome of a risk-benefit trade-off; (2) controlling personal information after disclosure and perceiving the disclosed personal information as sensitive determined the risk of potential privacy loss.

Conclusion: To encourage the adoption of personalised dietary recommendations, for individuals with high levels of autonomous motivation emphasis should be on benefits and its determinants. For those with high levels of controlled motivation, it is important to focus on risk-related issues such as information sensitivity.     

The effect of motivation and word characteristics on recognition

Two tachistoscopic studies assessed the effects of motivation on high-speed word processing. Study 1 assessed the effect of anxiety and Study 2 the effect of hunger compared to satiation. Words differed in interletter associative frequency (generated value), Thorndike-Lorge word frequency, and categories. In both studies, all three word variables yielded significant main effects. Motivational relevance of words did not significantly alter word recognition, the food words being most readily recognized and negatively emotional words least readily recognized in both studies. Anxiety did not have a significant effect, but hunger in interaction with word characteristics was found to be facilitating. Contrary to Hullian theory regarding word dominance and drive interaction and to Broadbent's "filtering" hypothesis, hunger in comparison to satiation increasingly facilitated word recognition the more infrequent the words and the more rare were the interletter associations.     

The release of catecholamines by shocks and stimuli paired with shocks

One monkey and five baboons were surgically prepared so that heart rate and blood pressure could be monitored continuously, and an extra-corporeal blood path was established to detect the secretion of epinephrine (adrenaline) and norepinephrine (noradrenaline). A respondent conditioning procedure was used in which a tone was paired with electric shocks. Epinephrine, but not norepinephrine was released by shocks, and a corresponding release was demonstrated by the tone alone. Heart rate and blood pressure changes were also elicited by shocks and by the tone.     

Stimulus and response contributions to the children's reaction-time repetition effect

Adults and 8-, 10-, 12-, and 14-year olds completed a serial reaction-time task with two stimuli mapped to each of two responses and 100-, 500-, and 1000-msec response-stimulus intervals (RSIs). Trials were classified as (1) identical (same stimulus and same response on two consecutive trials), (2) response equivalent (different stimulus but same response on two consecutive trials), or (3) different (different stimulus and different response on two consecutive trials). Identical and different trials were compared as a general indication of repetition effects. Response-equivalent minus identical reaction time identified stimulus contributions, and different minus response-equivalent reaction time identified response contributions. Adults received a repetition advantage at all RSIs and children received a repetition advantage at 500- and 1000- but not 100-msec RSIs. Stimulus contributions accounted for the repetition effect for both adults and children. At the 500- and 1000-msec RSIs, both the overall repetition effect and stimulus contribution were positive and decreased in magnitude as age increased. The response contribution was independent of RSI and was negative for 8- and 10-year-olds and near zero or positive for older performers. At the longer RSIs, positive stimulus contributions were sufficient to overcome the negative response contributions present for younger children.