Improvement in Vernier acuity in adults with amblyopia. Practice makes better

PURPOSE: To determine the nature and limits of visual improvement through repetitive practice in human adults with naturally occurring amblyopia. METHODS: A key measure the authors used was a psychophysical estimate of Vernier acuity; persons with amblyopia have marked deficits in Vernier acuity that are highly correlated with their loss of Snellen acuity. The experiment consisted of three phases: pretraining measurements of Vernier acuity and a second task (either line-detection thresholds or Snellen acuity) in each eye with the lines at two orientations; a training phase in which observers repetitively trained on the Vernier task at a specific line orientation until each had completed 4000 to 5000 trials; and posttraining measurements (identical to those in the first phase). Two groups of amblyopic observers were tested: novice observers (n = 6), who had no experience in making psychophysical judgments with their amblyopic eyes, and experienced observers (n = 5), who had previous experience in making Vernier judgments with their amblyopic eyes (with the lines at a different orientation) using the signal-detection methodology. RESULTS: The authors found that strong and significant improvement in Vernier acuity occurs in the trained orientation in all observers. Learning was generally strongest at the trained orientation but may partially have been transferred to other orientations (n = 4). Significant learning was transferred partially to the other eye (at the trained orientation) in two observers with anisometropic amblyopia. Improvement in Vernier acuity did not transfer to an untrained detection task. In two observers, the improvement in Vernier acuity was accompanied by a commensurate improvement in Snellen acuity. CONCLUSIONS: Some adults with amblyopia retain a significant degree of neural plasticity. Although several observers (primarily novices) showed evidence of generalized learning, several amblyopic patients showed evidence for improvement that was orientation and task specific. In this latter group of observers, the improvement appeared to reflect alterations that were, at least in part, in early neural processes that were orientation specific and were localized beyond the site of convergence of the two eyes.     

Does practice in orientation discrimination lead to changes in the response properties of macaque inferior temporal neurons?

We trained two rhesus monkeys in a task in which they had to judge whether or not two successively presented gratings differed in orientation. In a first experiment, we trained a monkey for only a restricted set of orientations and then recorded from the temporal cortical visual area (TE) while he made discriminations at trained and untrained orientations. Although this orientation-selective practice induced a marked anisotropy in his behavioural performance, this was not matched by a similar anisotropy in single-cell response properties. In a second experiment, we compared the response properties of TE cells in two monkeys before and after practice in the discrimination of small orientation differences. The training had no effect on either the responsiveness or the orientation tuning. We did, however, observe alterations in the pattern of response modulations induced by the behavioural context. However, these changes with practice, although present in both monkeys, were not consistent from animal to animal. The relevance of these findings for the functional significance of behavioural context dependencies of TE cells, as well as for the plasticity of TE responses, is discussed.     

Decoding Speech Prosody: Do Music Lessons Help?

Three experiments revealed that music lessons promote sensitivity to emotions conveyed by speech prosody. After hearing semantically neutral utterances spoken with emotional (i.e., happy, sad, fearful, or angry) prosody, or tone sequences that mimicked the utterances' prosody, participants identified the emotion conveyed. In Experiment 1 (n=20), musically trained adults performed better than untrained adults. In Experiment 2 (n=56), musically trained adults outperformed untrained adults at identifying sadness, fear, or neutral emotion. In Experiment 3 (n=43), 6-year-olds were tested after being randomly assigned to 1 year of keyboard, vocal, drama, or no lessons. The keyboard group performed equivalently to the drama group and better than the no-lessons group at identifying anger or fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visuo-motor adaptation: evidence for a distributed amplitude control system

We investigated the constraints for visuo-motor adaptation in human pointing movements. Subjects pointed at sequentially presented visual targets while visual feedback about their finger position was either absent (pre- and post-period), or was manipulated such as to require a gradual reduction of response amplitude (per-period). We found that response amplitudes were smaller during the post- than during the pre-period, which documents the existence of adaptation to distorted visual feedback. We further found that adaptation can transfer fully to untrained amplitudes (Exp. 1), although the amount of transfer may be reduced if trained and untrained amplitudes are substantially different (Exp. 2). However, selective adaptation of one amplitude but not another can also be yielded if the paradigm explicitly asks for it (Exp. 3), and if the two amplitudes differ by more than about 10 cm (Exp. 4). We conclude from these findings that the adapted mechanism consists of amplitude-specific elements, tuned to amplitude spans of some 10 cm.     

Mental rotation and number conservation: Are they related?

Attempted to determine (a) whether 4- and 5-yr-old children can evoke and use kinetic imagery (measured via mental rotation procedures) and (b) whether the ability to use kinetic imagery depends on the attainment of concrete operations (measured via a test of number conservation). To test kinetic imagery ability, 24 4-yr-olds and 24 5-yr-olds were asked to make same–different judgments on pairs of forms that differed in angular orientation. Half of the Ss had been trained to rotate one form into congruence with the other to make judging easier, while the other half had not been given training. It was hypothesized that if children of this age both use and evoke kinetic imagery, then both the trained and untrained Ss should yield the linear trends in reaction time indicative of kinetic imagery. If children can use but not evoke kinetic imagery, it was expected that the trained Ss would yield these linear trends while the untrained children would not. Results show that 4- and 5-yr-olds used and evoked kinetic imagery. Their performance was compared to that of a group of 24 adults. 26 of the children also were given a test of number conservation. Results yield no evidence of association between kinetic imagery and conservation, suggesting that the ability to use kinetic imagery does not depend on the attainment of concrete operations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Letter training and its effect on the development of beginning reading skills.

The effect of training to improve letter-naming speed on beginning reading skill was evaluated with 39 1st-grade students. Ss were randomly assigned to training and control groups and were administered curriculum-based measures of reading at pretraining, post-training, and follow-up. Trained Ss demonstrated significantly faster letter-naming speed at post-training assessment as compared with untrained Ss. However, the difference in letter-naming speed did not lead to a significant difference in overall measured reading skill as evaluated by an analyses of covariance. Scores for 1 of the 4 reading measures (Fall passage oral reading rate) demonstrated a significant difference at post-training, but were not significant at follow-up. In 2 of the 3 remaining measures of beginning reading skill, differences between the mean scores of trained and untrained Ss were greatest at points where the assessment of skills most closely matched the content of classroom instruction. However, these differences were not statistically significant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Uniform discrimination of pattern orientation by honeybees

To explore how honeybees, Apis cerana, discriminate the orientation of patterns, we trained workers to discriminate between a black stripe of a certain orientation on a white disc and a pure white disc. We tested trained bees for their ability to discriminate between the trained orientation and deviations from it. This was done either in a dual choice situation where the bees had to choose between the trained orientation and one deviation from it at a time, or in a multiple choice situation where bees had to choose simultaneously between the trained orientation and 11 successive deviations from it. In the dual choice situation, bees did not discriminate behaviourally between the trained orientation and deviations up to 25 degrees, whereas in a multiple choice situation, they discriminated between the trained orientation and a deviation of 15 degrees or more. Thus, orientation can be analysed more precisely in multiple choice experiments. The response of the bees was independent of the orientation of the trained orientation; the 12 different trained orientations all yielded identical results. This finding, considered together with a model that we present for orientation discrimination, suggests that at least three orientation-sensitive channels (a neuron or a set of neurons that respond maximally to a particular orientation) participate in the analysis of pattern orientation. (c) 1998 The Association for the Study of Animal Behaviour.     

Effects of communication skill training on high school students' ability to function as peer group facilitators.

Conducted a study with 60 high school students to assess the effect of training vs nontraining on their ability to function as peer facilitators in a group setting. R. Carkhuff's Helping and Human Relations (1969) provided the basis for the training. Expert judges and peers rated training Ss significantly higher as group facilitators than they rated untrained students. In addition, trained Ss functioned at significantly higher levels of communication than did their untrained counterparts. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of fatigue and chewing training on maximal bite force and endurance

The purpose of the study was to evaluate the effects of chewing training on the strength and resistance to fatigue of the masticatory muscles. Twenty-five healthy adults were divided into an experimental group (7 men, 10 women) and a control group (4 men, 4 women). The experimental group chewed a special hard chewing gum one hour daily for 28 days. Maximal bite force and endurance were measured. The maximal bite force already showed a significant increase in the experimental group by the middle of the experimental period (p < 0.05), reached the highest values by the end of the training period (p < 0.001), and also remained at high levels 2 weeks after (p < 0.001). Subjects with weak initial maximal bite force values showed the highest increase in their strength after training (r = -0.66, p < 0.01). This type of training did not influence the endurance time during maximal clenching or the reduction in this endurance time after a dynamic fatigue test. No significant differences were found between the maximal bite force before and that after the fatigue test under either untrained or trained conditions. In the control group no significant differences were found between the recording sessions. In conclusion, 4 weeks training with a hard chewing gum seems to influence the functional capacity of the masticatory muscles and increase their strength.     

Effects of client affective self-disclosure and counselor experience on counselor verbal behavior and perceptions.

60 untrained, trained, and professional counselors (average age 20 yrs, 26 yrs, and 38 yrs, respectively) responded to an audio presentation of client affective self-disclosures consisting of either high or low intimacy content. Quality and type of response were measured. Ss then completed a reaction form to assess their clinical impressions of the client. No intimacy effects were found. In contrast, consistent differences for experience occurred. Results indicate that untrained Ss made lower quality responses than either trained or professional Ss with no differences between professionals and counselors-in-training. In terms of response type, untrained Ss relied on direct guidance and silence; trained Ss preferred reflection, and professionals utilized silence, open question, and reflection. When silence as an initial response was removed from consideration, the preferred mode of responding for untrained and trained Ss was strengthened. In contrast, professionals utilized 2 responses (reflection and open question) equally. Finally, the counselor reaction data indicated that untrained Ss had less liking for the client as a person and viewed the client as less motivated to change than trained or professional Ss. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working memory training in older adults: Evidence of transfer and maintenance effects.

Few studies have examined working memory (WM) training-related gains and their transfer and maintenance effects in older adults. This present research investigates the efficacy of a verbal WM training program in adults aged 65–75 years, considering specific training gains on a verbal WM (criterion) task as well as transfer effects on measures of visuospatial WM, short-term memory, inhibition, processing speed, and fluid intelligence. Maintenance of training benefits was evaluated at 8-month follow-up. Trained older adults showed higher performance than did controls on the criterion task and maintained this benefit after 8 months. Substantial general transfer effects were found for the trained group, but not for the control one. Transfer maintenance gains were found at follow-up, but only for fluid intelligence and processing speed tasks. The results are discussed in terms of cognitive plasticity in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Training induced adaptation of skeletal muscle and metabolism during submaximal exercise

1. Six subjects were trained using a one-leg bicycle exercise for 2 months. The untrained leg served as control. After the training period, muscle oxidative capacity, determined as succinate dehydrogenase activity, was 27% higher in the trained (as opposed to the control) leg (P < 0.05).2. When the subjects in this situation performed a 1 h two-legged submaximal bicycle exercise bout (150-225 W), determinations of V(O2) of the single leg (leg blood flow x (A-V)(O2) difference) revealed that they appeared to choose to work harder with their trained than with their untrained leg, so as to make the relative loads for the two legs the same.3. Determinations of O(2) and CO(2) on femoral arterial and venous blood demonstrated that the R.Q. was lower in the trained as compared to the untrained leg, 0.91 cf. 0.96 (10 min) and 0.91 cf. 0.94 (50 min) (P < 0.05).4. That metabolism of fat was more pronounced in the trained leg was further supported by the finding of a significant net uptake of free fatty acids in this leg only. Moreover, a lower release of lactate from the trained leg was demonstrated.5. It is suggested that the shift towards a more pronounced metabolism of fat in the trained leg is a function of an increased muscle oxidative capacity.     

Monoamine responses to acute and chronic aerobic exercise in normotensive and hypertensive subjects

OBJECTIVES: The purpose of the present study was to compare the plasma and serum monoamine levels in sedentary, untrained normotensive and hypertensive men at rest with levels measured after an acute bout of exercise and to compare similar measurements following a 12-week aerobic training program. PLACE OF STUDY: The data obtained for this study was collected from a clinic for the prevention of heart disease and cardiac rehabilitation (FITCOR) and analyzed in the Federal University of S?o Paulo (EPM), Laboratory of Experimental Neurology. SUBJECTS: Two groups of untrained male subjects, i.e., normotensive (N = 16) and hypertensive (N = 19), were submitted to an acute bout of exercise to analyze the acute effect of exercise on the monoamine levels. To study the chronic effect of exercise (physical training program), some individuals of each group were arranged in two other groups; normotensive (N = 11) and hypertensive (N = 8). MEASUREMENT: Plasma catecholamines and serum serotonin levels were determined by high performance liquid chromatography coupled with electrochemical detection. RESULTS: A significant reduction in diastolic blood pressure at rest was observed in the hypertensive group after the physical training program (p < 0.05). Only the mean plasma noradrenaline concentration increased significantly post-exercise in all groups of individuals (acute effect of exercise--p < 0.01 for untrained normotensive and hypertensive; chronic effect of exercise--p < 0.001 for untrained and trained normotensive, p < 0.01 for untrained and trained hypertensive). CONCLUSION: These data show the beneficial effect of physical exercise in reducing the blood pressure in hypertensive patients, which does not seem to be related to changes in circulating monoamines.     

Field test of the cognitive interview: Enhancing the recollection of the actual victims and witnesses of crime.

The Cognitive Interview was tested in the field to enhance the recollection of actual victims and witnesses of crime. The technique is based on laboratory-tested principles of memory retrieval, knowledge representation, and communication. Seven experienced detectives from the Metro-Dade Police Department were trained to use the technique and were compared with 9 untrained detectives. Before and after training, all detectives tape-recorded interviews with victims and witnesses of crime. The trained detectives elicited 47% more information after than before training, and 63% more information than did the untrained detectives. Overall collaboration rates (94%) were extremely high and were equivalent for pre- and posttrained interviews. Because the Cognitive Interview reliably enhances memory and is easily learned and administered, it should be useful for a variety of investigative interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual discrimination of orientation by the goldfish (Carassius auratus).

Trained 4 large goldfish to choose a vertically oriented grating when it appeared along with gratings of other orientations on a circular field. Ss produced psychometric functions of responses correct as a function of stimulus orientation. 2 psychophysical methods, constant stimuli and stimulus tracking, yielded similar orientation thresholds which ranged from about 14 to 30. of tilt for the 4 Ss. One of these Ss and 2 untrained Ss were subsequently trained to choose a grating tilted 45., and yielded similar thresholds, ranging from 15 to 28.. Results are discussed in relation to orientation detectors which have been investigated neurophysiologically in the visual systems of several species. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental change in unilateral olfactory habituation is mediated by anterior commissure maturation.

Habituation of an orienting response in rat pups was used to study the development of the anterior commissure (AC) and its role in olfactory memory. Six- and 12-day-old pups received odor presentations to one side of their olfactory system and were tested later for habituation to additional presentations made to either the trained or untrained side. Six-day-old pups remembered only on the trained side. 12-day-old pups remembered when tested on either side. Transection of the AC in 12-day-old pups before, but not after, training prevented the transfer of memory. Thus, between 6 and 12 days of age, olfactory cross-projections carried in the AC mature and provide a functional substrate for transfer, at the time of training, of a form of olfactory learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word Learning and Individual Differences in Word Learning Reflected in Event-Related Potentials.

Adults learned the meanings of rare words (e.g., gloaming) and then made meaning judgments on pairs of words. The 1st word was a trained rare word, an untrained rare word, or an untrained familiar word. Event-related potentials distinguished trained rare words from both untrained rare and familiar words, first at 140 ms and again at 400-600 ms after onset of the 1st word. These results may point to an episodic memory effect. The 2nd word produced an N400 that distinguished trained and familiar word pairs that were related in meaning from unrelated word pairs. Skilled comprehenders learned more words than less skilled comprehenders and showed a stronger episodic memory effect at 400-600 ms on the 1st word and a stronger N400 effect on the 2nd word. These results suggest that superior word learning among skilled comprehenders may arise from a stronger episodic trace that includes orthographic and meaning information and illustrate, how an episodic theory of word identification can explain reading skill. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interhemispheric transfer of visual discriminations in split-chiasm monkeys (Macaca nemestrina) and its measurement.

The interhemispheric transfer of visual discriminations in split-chiasm monkeys (Macaca nemestrina) was assessed by training with one eye to a criterion level, then testing either with that same eye (control) or with the other eye (transfer). The difference between these 2 values was the loss due to transfer. A computer simulation suggested that the usual savings score could grossly misestimate transfer ability. In addition, stimuli with comparable left and right halves were used to minimize the effect of the bilateral hemianopia caused by chiasm section. Performance with the untrained eye was slightly, but statistically significantly, poorer than with the trained eye. No evidence of the phenomena of "learning to transfer" was found (i.e., there was no improvement in transfer ability in relation to concurrent intrahemispheric controls). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neural cell adhesion molecules, learning, and memory in the domestic chick

The intermediate and medial hyperstriatum ventrale (IMHV) of the chick forebrain is a site of recognition memory for the learning process of imprinting. The results reported here demonstrate that neural cell adhesion molecules (NCAMs) play a time-dependent role in this recognition memory. Dark-reared chicks were trained, tested, and assigned a preference score as a measure of learning. Chicks with high preference scores were designated good learners and those with lower preference scores, poor learners. Controls were untrained. Tissue was removed, 9.5 hr or 24 hr after training, from the left and right IMHV, hyperstriatum accessorium, and posterior neostriatum. Three major NCAM isoforms (180, 140, and 120 kDa) were assayed. At 24 hr only, there was in left IMHV significantly more NCAM (for each isoform) in good learners than in the other 2 groups, and also a significant correlation between the amounts of NCAM and preference scores for all isoforms; the amount predicted by each regression line at preference score 50 (no learning) did not differ significantly from the mean value for untrained controls. There were no learning-related effects in either the hyperstriatum accessorium or the posterior neostriatum.