Specific-cue effects of interpolated movements on distance and location retention in short-term motor memory

A short-term motor retention paradigm was used to examine the effect of interpolated movements on the recall of individual distance- and location-cue information. Subjects were instructed to learn either a distance or a location cue during the execution of simple, discrete original movements. Interpolated movements were then made which varied and repeated distance and location either individually or jointly. Changes in variable, absolute, and algebraic error from immediate to delayed recall were totally determined by interpolation of the individual instructed cue. No added recall changes were produced by interpolation of noninstructed cues. The data were interpreted as supporting the presence of a stimulus-selection process that dissociates kinesthetic information as a function of instructional set. The effects of inter-poated movements, then, are determined partially by this selection process.     

The effects of fading on the acquisition and retention of oral reading

Comparisons were made between reading programs that involved superimposition of correlated pictoral and printed stimuli, fading of the pictoral stimuli, and overt observing (touching) responses. Nursey school children aged 4 to 5.8 yr learned and retained oral reading behavior better when fading was used; observing responses had no effect.     

Contextual interference effects on the acquisition and retention of fundamental motor skills

This study was designed to examine the effect of three practice models (repetitions, random, and combined) on the acquisition and retention of fundamental motor skills. 54 girls in Grade 4 were randomly assigned to the three different practice groups who practiced three skills of ball rolling, racket striking, and ball kicking. All subjects received pretests posttests, and a 3-wk, retention test. Performance was significantly improved during practice in the three groups for the three skills. The repetitions group performed better than the other two groups at the end of practice. The contextual interference effect in retention was only shown for the racket-striking skill, in which the random group was significantly better than the repetitions and the combined groups. An attempt was made to attribute that specific result to the special characteristics of the striking skill in this study as an open skill with which subjects had a previous experience.     

Contextual interference effect on acquisition and retention of pistol-shooting skills

The effects of contextual interference on learning pistol-shooting skills in a natural training environment were examined. The shooting skills consisted of three "stages" with different requirements for the skill variations commonly used in the field. 12 participants were randomly assigned into one of two practice conditions, blocked vs serial. Following a 20-min. safety and skill instructional session, Blocked group practiced 10 trials in a row at each stage, while Serial group performed 5 trials in a row for each of the three stages and then repeated the cycle. Both groups completed a total of 30 practice trials over the three stages. A 10-min. rest interval was provided prior to a retention test which included 9 trials (3 trials at each stage in a blocked format). Results based on the data of Stage III, the most complex skill among the three stages, showed a pattern consistent with previous findings that practicing in the serial schedule depressed performance during initial training but maintained the performance better at retention, relative to the blocked practice.     

Imagery ability and the acquisition and retention of movements

In this study, we examined the relationship between imagery ability, as measured by the Movement Imagery Questionnaire (MIQ), and the acquisition, retention, and reacquisition of movements. Based on their MIQ scores, 10 subjects were selected for the following imagery groups: high visual/high kinesthetic (HH), high visual/low kinesthetic (HL), and low visual/low kinesthetic (LL). The subjects learned four movements to a criterion level. Before each trial, subjects kinesthetically imaged the movement about to be produced. Following each acquisition trial, subjects were provided visual feedback. The acquisition phase was followed by a 2-day retention interval, a retention test consisting of three trials on each movement (no feedback provided), and a reacquisition phase. The HH group acquired the movements in the least number of trials, the LL group required the greatest number of trials, and the HL group required an intermediate number of trials. The data for the reacquisition phase showed the same trend. There was only weak evidence for a relationship between imagery ability and the retention of the movements. These findings support the position that high imagery ability facilitates the acquisition, but probably not the short term retention, of movements.     

Subjects' skill and biphasic effects of met-enkephalin upon the acquisition and retention of a perceptual motor task

The effects of met-enkephalin on the acquisition and retention over 10 days of a perceptual motor skill were investigated. Mice were randomly assigned to either one of two experimental groups (1-mg or 3-mg injections per 1-kg of body weight of met-enkephalin) or one of two control groups (dH2O injections). During the acquisition phase of the study, they were separated into "slow" and "fast" learners on the basis of their skill in negotiating a water maze. The results indicated an inhibitory effect of met-enkephalin in the 3-mg condition in the retention phase of the experiment. Subjects' skill was not implicated as a critical factor in retention of this simple task.     

Imagery ability in recall of distance and location information

The role of visual imagery in short-term retention of movement end locations and distances was examined by comparing performances of subjects with extreme scores on the space relations section of the Differential Aptitude Test. Twelve HIGHS and twelve LOWS were tested on reproduction accuracy of six distances and six end locations immediately following presentation a 30-sec rest, a 30 sec imaginal rehearsal condition, and a 30-sec imaginal distraction condition. Initial analysis of the data provided little support for the hypothesis that HIGHS would reproduce criterion locations with more accuracy than LOWS. However, when scores of HIGHS reporting use of an imaginal coding strategy (HIGHS) were compared with LOWS who did not (LOWS), several expected findings were disclosed. HIGHS reproduced end locations with significantly less error in the immediate and imaginal rehearsal conditions, and as expected, accuracy scores for HIGHS and LOWS did not differ for the distance task. The findings suggest that when subjects employ an imaginal coding strategy, visual imagery ability may be an important factor in the retention of location information, but of little functional significance in the recall of distance.     

Three feedback methods in acquisition and retention of badminton skills

Comparison of three different feedback methods using information about the correct execution of the technique, errors of execution, and a combination of these on the acquisition and retention of two badminton skills of different difficulty were examined. Participants were 48 young male athletes, 10 to 14 years of age, with 2 to 4 years of training. They were divided into three equal groups and instructed on the long forehand serve, a more difficult serve than the short backhand. The first group received instructions for correct execution, the second group received instructional cues on errors of execution, and the third group received instructions on errors and how to correct them. The training program lasted 12 practice units. There was a pretest, a posttest after the end of the 10-wk. training program, and 2 wk. later, a retention test. A three-way (2 difficulty x 3 groups x 3 measures) analysis of variance with repeated measures on the last factor was applied to analyze scores with the three practice methods of corrective feedback for the two badminton skills. Analysis showed the group receiving correct technique information had increased scores on both skills. The group receiving information on errors increased their scores on the less difficult skill. The group receiving information on errors and correct technique increased their scores on the more difficult skill. Physical education teachers or coaches teaching skills to young participants should consider difficulty of skills and use appropriate corrective feedback for better acquisition and retention of sport skills.     

Associative learning acquisition and retention depends on developmental stage in Lymnaea stagnalis

Associative learning dependent on visual and vestibular sensory neurons and the underlying cellular mechanisms have been well characterized in Hermissenda but not yet in Lymnaea. Three days of conditioning with paired presentations of a light flash (conditional stimulus: CS) and orbital rotation (unconditional stimulus: UCS) in intact Lymnaea stagnalis results in a whole-body withdrawal response (WBWR) to the CS. In the current study, we examined the optimal stimulus conditions for associative learning, including developmental stage, number of stimuli, interstimulus interval, and intertrial interval. Animals with a shell length longer than 18 mm (sexually mature) acquired and retained the associative memory, while younger ones having a shell length shorter than 15 mm acquired but did not retain the memory to the following day. For mature animals, 10 paired presentations of the CS and UCS presented every 2 min were sufficient for the induction of a WBWR to the CS. Furthermore, animals conditioned with the UCS presented simultaneously with the last 2 s of the CS also exhibited a significant WBWR in response to the CS. Blind animals did not acquire the associative memory, suggesting that ocular photoreceptors, and not dermal photoreceptors, detected the CS. These results show that maturity was key to retention of associative learning.     

Differential use of distance and location information for spatial localization

Five experiments are reported in which subjects judged the movement or spatial location of a visible object that underwent a combination of real and induced (illusory) motion. When subjects attempted to reproduce the distance that the object moved by moving their unseen hands, they were more affected by the illusion than when they pointed to the object's perceived final location. Furthermore, pointing to the final location was more affected by the illusion when the hand movement began from the same position as that at which the object initially appeared, as compared with responses that began from other positions. The results suggest that people may separately encode two distinct types of spatial information: (1) information about the distance moved by an object and (2) information about the absolute spatial location of the object. Information about distance is more susceptible to the influence of an induced motion illusion, and people appear to rely differentially on the different types of spatial information, depending on features of the pointing response. The results have important implications for the mechanisms that underlie spatially oriented behavior in general.     

The perception of distance and location for dual tactile pressures

The concept that distance on the skin is frequently misperceived was first reported over a century ago by Weber. Weber and others have reported that the apparent distance between pressure stimuli fluctuates with both body site and stimulus orientation. The present study confirms these effects and shows that the misperceptions are usually compressive in nature. It further establishes that errors in perceived distance correspond to errors in perceived location, indicating that an interaction exists between the perceptual processes responsible for percepts of tactile location and distance. Perceived location depends on the relationship of a tactile stimulus both to the body frame and to nearby stimuli, and the effect of nearby stimuli is to induce a perceptual affinity between sensations of pressure. These results are discussed in relation to the more frequently examined dynamic illusions of tactile distance (tau phenomenon) and location (the cutaneous rabbit).     

Effect of intermittent reinforcement on acquisition and retention in delayed matching-to-sample in pigeons

Experiments 1 and 2 involved independent groups that received primary reinforcement after a correct match with a probability of 1.0, .50 or .25. Correct matches that did not produce primary reinforcement produced a conditioned reinforcer. Both experiments revealed little evidence that acquisition or retention was adversely affected by use of intermittent reinforcement. Experiment 3 involved a group that received 100% reinforcement and two others that received 25% reinforcement, one of which received conditioned reinforcement and the other did not. Following acquisition and retention testing, birds in group 100% and group 25% with conditioned reinforcement were exposed to 25% reinforcement and no conditioned reinforcement. Results revealed that conditioned reinforcement was important in promoting acquisition but was irrelevant in maintaining performance. It was concluded that intermittent reinforcement, especially when combined with conditioned reinforcement during acquisition, supports levels of acquisition and retention comparable to that of continuous reinforcement. Theoretically, the findings are consistent with an extension of Blough's instance-based theory of discrimination performance and, practically, they suggest that use of intermittent reinforcement could result in increased efficiency and economy in labs using delayed matching.     

Selective lesions in the temporal-hippocampal region of the rat: effects on acquisition and retention of a visual discrimination task.

The first purpose of this study was to investigate whether lesions in the temporal region may affect acquisition or retention of a discrimination task. In Experiment 1, rats with lesions of the temporal cortex (TC), the lateral entorhinal cortex (LEC), or their interconnections were tested postoperatively in simultaneous brightness discrimination. The results show that neither TC lesions nor LEC lesions affected acquisition of the task, and only LEC lesions impaired retention. TC/LEC transections impaired both acquisition and retention. The second purpose was to investigate effects of hippocampal lesions and perforant path transections on the discrimination task (Experiment 2). Both hippocampal and perforant path lesions impaired acquisition of the task, whereas retention was unaffected. It is suggested that TC and LEC are primarily involved in information storing and that hippocampal function is primarily involved in information processing.     

Semantic distance effects on object and action naming

Graded interference effects were tested in a naming task, in parallel for objects and actions. Participants named either object or action pictures presented in the context of other pictures (blocks) that were either semantically very similar, or somewhat semantically similar or semantically dissimilar. We found that naming latencies for both object and action words were modulated by the semantic similarity between the exemplars in each block, providing evidence in both domains of graded semantic effects.     

Medial auditory thalamus inactivation prevents acquisition and retention of eyeblink conditioning

The auditory conditioned stimulus (CS) pathway that is necessary for delay eyeblink conditioning was investigated using reversible inactivation of the medial auditory thalamic nuclei (MATN) consisting of the medial division of the medial geniculate (MGm), suprageniculate (SG), and posterior intralaminar nucleus (PIN). Rats were given saline or muscimol infusions into the MATN contralateral to the trained eye before each of four conditioning sessions with an auditory CS. Rats were then given four additional sessions without infusions to assess savings from the initial training. All rats were then given a retention test with a muscimol infusion followed by a recovery session. Muscimol infusions through cannula placements within 0.5 mm of the MGm prevented acquisition of eyeblink conditioned responses (CRs) and also blocked CR retention. Cannula placements more than 0.5 mm from the MATN did not completely block CR acquisition and had a partial effect on CR retention. The primary and secondary effects of MATN inactivation were examined with 2-deoxy-glucose (2-DG) autoradiography. Differences in 2-DG uptake in the auditory thalamus were consistent with the cannula placements and behavioral results. Differences in 2-DG uptake were found between groups in the ipsilateral auditory cortex, basilar pontine nuclei, and inferior colliculus. Results from this experiment indicate that the MATN contralateral to the trained eye and its projection to the pontine nuclei are necessary for acquisition and retention of eyeblink CRs to an auditory CS.     

Effects of fimbria lesions on trace two-way active avoidance acquisition and retention in rats

The fimbria-fornix (FF) is the main subcortical input to the hippocampus. It has been shown that FF lesions facilitate performance on a standard-delay two-way active avoidance task (AA2), thought to involve implicit memory. The hippocampal region is required for explicit or relational memory. It has been proposed that the hippocampus and related structures might associate events that are separated in space or time and detect elements shared in common by such discontiguous episodes. Therefore, FF lesions would be expected to impair performance on a trace paradigm, which introduces an interval between the CS (conditioned stimulus) and the US (unconditioned stimulus) and is generally considered a model of explicit memory. We predicted that FF lesions would impair memory in a trace AA2 procedure, while the same lesions would facilitate memory in a standard delay version of the task. To test this hypothesis, two experiments were carried out in 102 male Wistar rats. The first experiment characterized the trace paradigm using this kind of conditioning and demonstrated that control rats were able to acquire and retrieve (24 h and 11 days postacquisition) the association between the CS (tone) and the US (electric foot shock) when a trace interval (5, 10, or 20 s) was interposed between both stimuli. In the second experiment, we investigated the effects of FF electrolytic lesions on the same task using delay and trace (10-s trace interval) paradigms. Surprisingly, FF lesions facilitated the acquisition and the 24-h retention of the AA2 not only on the standard delay paradigm, but also with the trace paradigm. We suggest that facilitative effects could be a result of impairment in contextual learning.