Subliminal stimulation and cognitive and motor performance

The present experiment investigated whether subliminally exposed messages affect cognitive and motor performance and whether personality factors can explain interindividual differences in this respect. According to Silverman (1983), people have a symbiotic fantasy, that is, a need for symbiotic oneness with the mother figure. This need can temporarily be satisfied by a tachistoscopic exposure of the message "Mommy and I are one." By relieving the unconscious conflict, psychological tension is reduced. Using these notions, it was hypothesized that different measures of performance should be improved. The results indicate that both cognitive performance, in terms of the ability to interpret incomplete and fragmented pictures, and motor performance, in terms of the ability to follow a printed line with a stylus, is improved by this procedure compared to that of a control group exposed to the neutral message "People are walking." However, it was not possible to relate these changes to individual differences in terms of the individual's structure of his psychological defense system as measured by the Defense Mechanism Test (DMT). Other possible explanations are discussed.     

The association of motor information and verbal information: a new perspective on the mechanism of the SPT effect

Current perspectives on the mechanism underlying the Subject Performed Task (SPT) effect have not yet reached a consensus. This study investigated whether the association between motor and verbal information is a key factor that explains the SPT effect. Experiment 1 and 2 tested whether motor and verbal retrieval memory performance were different when the association level was varied. Results showed that when subjects used low association learning materials, memory performance in either motor or verbal retrieval condition was significantly better than performance in the combined retrieval condition. Experiment 3 examined whether the level of association between motor and verbal information affects the SPT effect. Results revealed that the SPT effect disappeared when low association learning materials were used. Our findings imply that the high association level between motor and verbal information enables mutual activation of the two information types, leading to improved memory performance.     

Motivational Effects of Outcome Feedback on Motor Performance

This study examined the effects of success and failure feedback on subsequent motor performance. Based upon the general motivation (or level-of-aspiration) hypothesis, initial success should lead to better subsequent performance than does initial failure, while the reverse prediction was derived from the cognitive dissonance theory. To test these rival hypotheses, two experiments were conducted on undergraduate male students (n =120) performing a motor maze task. Initial failure improved subjects’ subsequent performance, thus supporting the dissonance theory. However, this effect was observed only under low-ego-involving conditions, thereby suggesting that the effects of dissonance and ego involvement are interdependent. The findings were discussed in terms of motivational and informational/attributional effects of outcome feedback on motor performance.     

Learning complex upper-limb movements through practicing movement elements

Upper-limb complex movements constitute a major part of our daily activities. Research shows complex movements are generated by sequences of movement elements represented by a unimodal bell-shaped velocity curve. We utilized this understanding in the field of motor skill acquisition and hypothesized that practicing a movement element of a complex movement trajectory will facilitate the performance on the respective complex movement trajectory. To test this, we designed an experiment where the control group learned a full complex trajectory, whereas the two elemental groups learned two different movement elements of the complex trajectory. The two main outcome measures explaining the performance were accuracy and speed. The elemental groups, after training on movement elements, significantly improved their speed and accuracy when tested on the full complex trajectory. The result illustrated that training on a movement element of a complex trajectory benefited the performance of the full complex trajectory. The two elemental groups showed similar improvements in the performance of the complex motor skill, despite obtaining training on different movement elements of the same complex movement. The findings show that complex movements can be learned by practicing their movement elements.     

Perceived credibility of a "neutral" abortion-related message and its sponsor

This study investigated the effect of a high- versus low-credibility sponsor on the perceived credibility of an abortion-related message. Three groups of subjects read a message that had been evaluated as "neutral" by officials of both "pro-life" and "pro-choice" groups. Sponsorship of the message was varied among the three groups (no sponsor; pro-life sponsor; pro-choice sponsor). Subjects rated the credibility of the message and credibility of the sponsor and also indicated their own attitudes toward abortion. Pro-life and pro-choice subjects did not differ in their perception of the nonsponsored message. The signature of a high-credibility sponsor improved the message's perceived credibility; however, the signature of a low-credibility sponsor did not diminish the message's credibility.     

Encouraging College Males to Perform Testicular Self-Examination: Evaluation of a Persuasive Message Based on the Revised Theory of Reasoned Action1

This study evaluated the effect of a persuasive message derived from a revised version of the theory of reasoned action on the performance of testicular self-examination (TSE). Subjects (114 male college students) were randomly assigned to listen to a taped persuasive message challenging unfavorable outcome beliefs (as suggested by the theory of reasoned action), a message on testicular cancer information, or no message. All subjects then completed a questionnaire operationalizing the components of the theory of reasoned action (revised to incorporate self-efficacy). As predicted, there was a significant relationship between exposure to the persuasive message and self-reported TSE performance (χ²(2) = 15.66, p < .0001). Sixty-three (71.23%) of the subjects contacted at a 4-week follow-up reported performing the exam. Of those, 44.23% had heard the theory-based message, 36.54% had heard the informational message, and 19.23% had not been exposed to a message. A path analysis of the relationships among components of the theoretical model provided partial support for the hypothesized causal pathways between message exposure and TSE intention and behavior.     

Scaling sporting equipment for children promotes implicit processes during performance

This study investigated whether children who used scaled equipment compared to full size equipment during a motor task demonstrated reduced conscious involvement in performance. Children (9–11 years) performed a tennis hitting task in two attention conditions (single-task and dual-task) using two types of equipment (scaled and full size). A more skilled group and a less skilled group were formed using hitting performance scores. The more skilled group displayed greater working memory capacity than the less skilled group. For both groups, hitting performance and technique were better when scaled equipment was used. Hitting performance when using scaled equipment was not disrupted in either group by a cognitively demanding secondary task; however, performance was disrupted in the less skilled group when using full size equipment. We conclude that equipment scaling may reduce working memory engagement in motor performance and discuss the findings in the context of implicit motor learning theory.     

A psychoanalytic reinterpretation of the effectiveness of systematic desensitization: Fact or fiction?

Silverman, Frank and Dachinger (1974) found support for their hypothesis that the effectiveness of systematic desensitization (SD) resides in its activation of unconscious, merging fantasies. Their subjects were subjected to a variant of SD. in which a procedure aimed at stimulating a fantasy of ‘merging with mother’ was substituted for muscle relaxation. This pro- cedure consisted of the tachistoscopic subliminal exposure of the symbiotic gratification stimulus mommy and i are one(experimental) or neutral stimulus people walking (control). The aim of the present study was to replicate their work with special reference to demand characteristics. using as subjects snake phobics. SD with a symbiotic gratification stimulus was not more effective than SD with a neutral stimulus, which may be explained by the fact that the neutral stimulus in the present study snake and I are one was more relevant than the neutral stimulus in the Silverman et al. study. Moreover, subjects with a therapy-set improved significantly more than subjects with a research-set.     

Practice effects on motor control in healthy seniors and patients with mild cognitive impairment and Alzheimer's disease

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of "on-line" correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.     

Increased Sensitivity to Changes in Visual Feedback With Practice

In recent work investigating motor learning, the focus has been on the effect of modifying feedback at different levels of learning. Results suggest that learning is specific to the practiced conditions and that this specificity increases with practice. In a replication and extension of this previous work, 3 groups (N = 30 subjects) practiced a sequential positioning movement: Controls performed 300 trials with visually presented on-line kinematic feedback, whereas the other 2 groups, low practice (LP) or high practice (HP), performed, respectively, 50 or 300 trials without feedback. Pretest and posttest sessions of 10 trials each were performed with the on-line feedback. All groups improved with practice. It was apparent that the HP group exhibited more of a performance decrement in the postest than the LP group did, suggesting that motor learning is the process of forming an increasingly specific sensorimotor representation. These results have implications for motor learning paradigms, models of motor learning, and training.     

Effects of maternal themes upon death imagery

Two samples (n = 47, n = 45) of women were studied to determine the impact of maternal messages upon death imagery as measured by the Holtzmann Inkblots. In both samples a maternal symbiotic message significantly decreased death imagery. A maternal monosymbiotic message resulted in decreased death imagery in only one sample. Control messages produced no changes in death imagery. The findings are congruent with theories that link death anxiety with concern about separation from parental figures.     

THE EFFECTS OF MESSAGE INTRODUCTION,MESSAGE STRUCTURE,AND VERBAL ORGANIZING ABILITY UPON LEARNING OF MESSAGE INFORMATION

This study focused primarily upon Ausubel's advance organizer concept as a relatively abstract message introduction. Subsumption theory suggests that the advance organizer should be superior in learning effects to an introduction of message main points and that the advance organizer should interact with message structure and verbal organizing ability. This study found no overall advance organizer superiority to other introduction conditions. However, simple interactions, which were analyzed to interpret a significant three-way interaction on one of two dependent variables, provided qualified support for first-order interaction hypotheses. These hypotheses predicted that the superiority of an advance organizer to other introduction conditions would be greater for a low-structure message than for a high-structure message and greater for low-ability subjects than for high-ability subjects. They also included a prediction that the superiority of a high-structure message to a low-structure message would be greater for high-ability subjects than for low-ability subjects. Analysis of serial position effects indicated primacy in recall under high-structure message conditions.     

Auditory evoked potentials during selective listening to dichotic speech messages

The sensitivity of the scalp-recorded, auditory evoked potential to selective attention was examined while subjects monitored one of two dichotically presented speech passages for content. Evoked potentials were elicited to irrelevant probe stimuli (vowel sounds) embedded in both the right- and the leftear’s message. The amplitude of the evoked potential was larger to probe stimuli embedded in the attended message than to probe stimuli in the unattended message. Recall performance was unaffected by the presence of the probes. The results are interpreted as supporting the hypothesis that this evoked potential sensitivity reflects an initial “input selection” stage of attention.     

Practice Effects on Motor Control in Healthy Seniors and Patients with Mild Cognitive Impairment and Alzheimer's Disease

ABSTRACT

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of “on-line” correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.     

Alcohol, subliminal stimulation, and disinhibitory processes

An experiment was performed to test the hypothesis that an unconscious conflict between a wish to attain symbiotic oneness with another person on the one hand and personal independence on the other, should be weakened by alcohol if the main effect of intoxication is to reduce the strength of psychological inhibitions. In turn, a reduction in such conflicts should improve motor performance. Data indicated no such effects, and it was concluded that the disinhibition hypothesis as an explanation of alcohol-related behavior was not supported.     

Motivational determinants of motor performance: The hidden second task

Summary The present study was designed to test facilitating and debilitating effects of motivational processes on motor behavior. It was predicted that motivational processes have a more pronounced effect on motor performance when control is frequently transferred to attentional mechanisms (i. e., early in the acquisition phase). The results were consistent with this expectation. A strong motive to achieve success and pretreatment designed to enhance achievement motivation were associated with an increase in the quality of performance. A strong tendency to engage in state-oriented cognitive activities, by contrast, (e.g., thinking about the potential threat to one's selfesteem resulting from failure) was associated with poorer performance, It is concluded that experiments on motor behavior in which subjects are instructed to perform a single motor task may actually involve dual-task (or even multiple-task) performance if some part of the subjects' attentional capacity is used for task-irrelevant cognitive activities.     

Relationship between extremities in motor performance

The purpose of the study was to examine the relationship between the extremities in different aspects of motor performance, including simple reaction time, choice reaction time, speed of movement, tapping speed, and coordination, i.e., speed of movement/accuracy. 186 healthy randomly selected right-handed subjects (93 men, 93 women; aged 21-70 years) were measured on a test battery of five tests for both hands and feet. Correlations between the extremities in motor performance were highest between hands (r=.71-.80, p<.001) or between feet (r=.57-.88, p<.001) depending on the complexity of response for all subjects. These relations remained at almost the same magnitude even when age was eliminated. Correlations between the upper and lower extremities were lower (r = .40-.62). Correlations between extremities were lower for one age group (21-30 years) than for all subjects (21-70 years). These results showed that the motor performance for the hands is not a very good indicator of the motor performance of the lower extremities, especially in a homogeneous age group, and it seems that the lower extremities should be studied with specific motor performance tests.     

Neuromuscular effects of shifting the focus of attention in a simple force production task

Research on the focus of attention has begun exploring the physiological changes that underlie the difference between internal and external foci of attention. However, previous electromyography studies have used dynamic tasks, making it difficult to interpret electrophysiological data. The authors analyzed how the focus of attention affects a subject's ability to perform an isometric force production task (focus was directed either at the force platform or the muscles responsible for force production). Subjects received practice without attentional focus instructions and then completed blocks of trials with an external and internal attentional focus separately. An external focus led to significantly less error overall and reduced surface electromyography activity with lower median power frequencies in the antagonist muscle, but attentional focus had no effects on the agonist muscle. Thus, an external focus of attention led to more efficient motor unit recruitment patterns (reduced cocontraction) and improved performance. Posttest surveys revealed subjects were aware of their improved performance with an external focus.     

Using Dual Tasks to Test Immediate Transfer of Training Between Naturalistic Movements: A Proof-of-Principle Study

Theories of motor learning predict that training a movement reduces the amount of attention needed for its performance (i.e., more automatic). If training one movement transfers, then the amount of attention needed for performing a second movement should also be reduced, as measured under dual task conditions. The authors’ purpose was to test whether dual task paradigms are feasible for detecting transfer of training between two naturalistic movements. Immediately following motor training, subjects improved performance of a second untrained movement under single and dual task conditions. Subjects with no training did not. Improved performance in the untrained movement was likely due to transfer, and suggests that dual tasks may be feasible for detecting transfer between naturalistic actions.     

Mechanical Efficiency and Metabolic Cost as Measures of Learning a Novel Gross Motor Task

“Efficiency,” or economy of movement with respect to energy expended in achieving the goal of the task, is implicit in many definitions of skilled performance. This study examined changes in mechanical efficiency and transport efficiency on a novel gross motor skill. The subjects were 5 physically fit adult males who were asked to perform 20 3-min trials walking on hands and feet (crawling) on a motor-driven treadmill at constant speed (0.76 mis). Transport efficiency, the metabolic cost of transporting the body mass a given distance at constant speed, improved significantly over practice trials. Mechanical efficiency, derived from the mechanical power output of individual body segments, showed an overall improvement of 13.7% by the last day of practice. Even though this improvement was not statistically significant it appears to be greater than that expected due to physiological training effects. The efficiency measures correlated significantly with changes in limb kinematics. It was concluded that with practice subjects tailored their movement pattern to produce energy efficient adaptations to task constraints. These findings provide empirical support for theoretical perspectives that have emphasized biological principles in the organization of motor coordination and control.