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Does sentence generation and/or stimulus emotionality enhance verbal memory in patients with neurological impairment? This question was addressed by testing 40 patients with unilateral stroke (20 with left-brain and 20 with right-brain damage) and 20 healthy control participants for recall and recognition of 48 target words. During encoding, emotional and nonemotional words were either presented in sentences (read condition) or used to form sentences (generate condition). Both word emotionality and generative processing improved memory performance in all groups. The authors suggest that a similar influence (i.e., cognitive activation) underlies both of these memory-enhancing effects, although the putative origins of the 2 effects are quite different. Neuropsychological underpinnings and clinical implications of these phenomena are discussed.

Four variations of a priming stimulus were introduced in three experiments, with the aim of examining the effects of encoding the prime on one target task (tachistoscopic recognition thresholds). The primes studied were words, color photographs, and outline drawings, followed by word and outline-drawing threshold measurement (Experiment 1); increased size and brightness reversal of words (Experiment 2); and mirror reversals of the prime (Experiment 3). Memory facilitation was weak or lacking for only the format changes in the first experiment. Facilitation was equal to that obtained with identical primes for the size and brightness alterations, and for the mirror reversals in Experiments 2 and 3. With weak or no facilitation in only one experiment, and strong facilitation in the others, we discuss the implications for the influence of encoding on priming effects.

The first two experiments found thresholds for classification into one of three categories of English words, Turkish words, and letter alternations to be significantly lower than thresholds for the identification of the specific items; parallel results were found with the two methods of measurement employed. Both thresholds were lowest for English words, and classification thresholds were lower for Turkish words than for letter alternations, but the identification thresholds of these two kinds of materials showed a reversal. The third experiment found classification thresholds for the same three types of materials to be higher than either of two three-choice identification thresholds, one a choice among three sametype items and the other, a choice among one English word, one Turkish word, and one letter alternation.

In three experiments, PA learning was followed by the measurement of tachistoscopic thresholds for the stimulus and the response words, as well as for control words not used in the learning. In all experiments, response words had significantly lower thresholds than did stimulus words. The variable of word frequency was found in the first experiment to affect control words more than the other words; furthermore, the contrast in thresholds for low and high frequencies was greater for stimulus words than for response words. Amount of S-R similarity was found, in Exp. II, to affect thresholds of stimulus words slightly more than thresholds of response words. In Exp. III, the amount of PA learning (50%, 100% and 150% criterion) exerted little influence on the recognition of the stimulus items; the response items exhibited a lowering of thresholds from the 50% to the 100% groups and a rise in threshold for the 150% criterion group.

Two experiments are reported which attempted to test implications of the shape-slant invariance hypothesis. Both experiments employed an apparatus in which variations in the slant and in the width settings of a rectangle were highly ambiguous and subject to instructional sets. In the first experiment, the stimulus was varied in both its width and its slant to achieve matches to four standard angles; the resultant width settings were found to be close to the projected widths of the obtained angles of slant. In the second experiment, width and slant were varied to match four standard widths; the projected widths of the obtained angles of slant did not differ from the obtained width settings.

The experiment reported was designed to explore the relationship between gradient of texture and monocular slantshape perception. The effects of instructional set and order of slant and shape judgments were studied in interaction with four patterns differing in regularity of texture. Judgments of slant and shape were made by the same Ss for all patterns at 20°, 45°, 60°slant for slant judgments and 0°, 20°, 45°, 60° for width judgments. There were three instructional groups. Within each group one half of the Ss made slant judgments first, the other half shape judgments first. For all patterns, accurate perception of the slant of patterned material resulted in increased compensation in width judgments. Apparent width was found to be a function of pattern and also subject to instructional manipulation.

Three experiments varied instructions and materials to compare the influence of auditory and visual imagery on free recall. Four kinds of words were presented: words with minimal imagery, words with both visual and auditory imagery, words with visual imagery, and words with auditory imagery. Experiment 1 (n = 48 volunteer college students) found instructions to form auditory images and words with auditory imagery to have the same advantage over control instructions and minimal imagery words as did visual imagery instructions and words with visual imagery. In Experiment 2 (n = 64 volunteer college students), groups instructed to form both auditory and visual imagery had incidental recall scores no greater than those of groups instructed to form only one kind of imagery. Experiment 3 (n = 64 volunteer college students) introduced augmented visual imagery (subjects drew a picture of the visual image) and augmented auditory imagery (subjects vocalized a sound modeled after the auditory image). Recall scores for the two augmented imagery groups were not significantly different from those for the two imagery groups. Results are discussed in terms of their implications for views of the cognitive representation of imagery.

Two methods for studying the effect of experimental set on word recognition were contrasted. After study of a set of incomplete sentences, thresholds for words which would complete the sentences were not significantly lower than for inappropriate words. However, a significant difference was found between such words when study of incomplete sentences alternated with threshold determinations.

The results of two discrimination experiments are presented. In the first, five-year olds learned size discriminations more rapidly with stereometric stimuli than with pattern stimuli; for seven-year olds there was little difference in learning the two discriminations. In Experiment II five-year olds learned size discriminations between perspective stimuli more rapidly than between control patterns without perspective. As in Experiment I both discriminations were equally easy for the seven-year olds. It was concluded that stimuli with depth provide added cues on which to base size discriminations.

It was hypothesized that the effect of irrelevant color cues on paired-associate learning might be generalizable to the tachistoscopic recognition situation. Words on colored backgrounds were learned by the free recall method to the criterion of one errorless trial. Half of these words on the same backgrounds and half on changed backgrounds were presented tachistoscopically along with unlearned control words on the colored backgrounds. Learned words on appropriate backgrounds had significantly lower thresholds than did those on inappropriate backgrounds; unlearned control words had significantly higher thresholds than did either of the types of learned words. Results were interpreted as supporting the hypothesis.

Three experiments employed various methods of PA learning; after learning, tachistoscopic thresholds were measured for stimulus (S) words, response (R) words, and control (C) words. Tachistoscopic measurements found thresholds for R words to be significantly lower than thresholds for S words following only two of the methods: standard anticipation with pronunciation of R words only and the discriminative situation, which also required pronunciation of R words only.

Some of the experiments which demonstrate the applicability of this postulate include (1) the group in which stimuli resulting from different drives become associated with distinct responses in the identical experimental situation;3 (2) studies employing differential states of the same drive to demonstrate their control of differing types of responses in the same problematical situation;4 and (3) an experiment in which drivestimuli were allowed to act in the same manner as external stimuli in

Winnick and Lerner studied the effects of three kinds of external distraction on intentional and incidental learning.' Although all three distractions effected a slowing down of intentional learning, no comparable effect was found on the amount of recall for irrelevant material shown simultaneously with the material to be intentionally learned. The apparent immunity of incidental learning to distractive effects was viewed as possibly due to the special characteristics of incidental learning. This type of learning, occurring as it does at the same time as other learning or with attention directed elsewhere, may be so highly selective as to occur even in the presence of distraction. On the other hand, the contrast shown by the effect of distraction on intentional learning and its lack of an effect on incidental learning may be a function of the experimental procedure. In the study cited, distraction was introduced only during intentional learning, not during the test of incidental recall; this raises the possibility that the findings reflect differential effects of performance. The present study, therefore, in its first experiment, attempted to determine whether the resistance of incidental learning to distraction would be maintained with distraction introduced during the attempt to recall the irrelevant material, as well as during the actual learning. Should incidental learning prove unaffected by distraction during both learning and recall, its immunity would be demonstrated at both the learning and the performance levels. A second experiment is also reported which, in contrast with the first, introduced a source of distraction inherent in the learning situation. Johnson and Thomson found incidental learning to occur when the incidental task (recall of nonsense-syllables being memorized by a partner) was a

When incidental learning has been demonstrated experimentally, it has often been presumed to be due to a set to learn which has transferred from previous learning-situations in which instructions to learn have been made explicit1 or to a set which generalizes from the specific instructions related to the relevant material.2 Such a set to learn incidental material as well as instructed material probably varies greatly with different Ss. The set may be one of which S is aware; noticing the irrelevant material, S may from time to time direct his attention toward it, possibly as a diversion from the instructed task; or even naive Ss, knowing that they are participating in an experiment, may be on the alert for a 'trick' and be aware of the possibility that they may be tested for knowledge of the irrelevant material. In fact, reports from Ss participating in incidental learning experiments indicate awareness varying from no notion at all that such learning might be tested to certainty that some such 'trick' is in the offing. Uncontrolled variation in the strength of the set to learn incidental material might be a serious source of error in experiments on incidental learning. Jenkins, in an analysis of his Ss' introspective reports, showed that variations in the set to learn on the part of incidental learners will greatly affect the amount of incidental learning which takes place.3 In his experiment, the Ss in the incidental learning group were told to read aloud words for other Ss to learn, then were themselves tested on the material. This is an experimental set-up which is probably highly conducive to the occurrence of a great 'deal of learning, since no other learning activity occurs simultaneously as the S reads out the material. In many experiments in this field, the learning in question is incidental to the learning of other material that S is instructed to accomplish. Although S may be aware of the irrelevant material, he has been clearly directed to learn other material. Under such circumstances, can there be a variation in the amount of incidental learning produced by different sets?