Further evaluation of self and peer judgements of speech with delayed auditory feedback

Fifteen undergraduate students recorded a standard reading passage under simultaneous auditory feedback (SAF) and delayed auditory feedback (DAF, 210 ms). These pairs were rated for articulation and fluency differences, reading rate differences, pitch differences, loudness differences, and overall differences in quality of speech by the fifteen speakers and by ten peer judges. Results suggest that naive speakers under DAF form a self-impression of the effects of DAF upon their speech that is not different from the qualitative ratings of independent peer judges. The hypothesis that there was no overall difference between self and peer ratings was not rejected. Implications for the use of DAF as a research or treatment modality, or as both, are discussed.     

Altered patterns of word associations in dementia and aphasia

The word associations of 38 demented, 17 aphasic, and 22 normal subjects were studied. Both normal and brain-injured subjects appear to make judgments about the grammatical class of the word stimulus. Certain stimulus words (especially nouns and adjectives) elicit paradigmatic responses whereas other words (especially verbs and adverbs) elicit syntagmatic responses. The mechanism producing syntagmatic responses seems relatively resistant to deterioration in dementia or aphasia. However, in dementia the mechanism that generates paradigmatic responses becomes progressively less efficient (possibly due to a loss of semantic markers) and consequently more random (idiosyncratic) responses emerge. Perseverative responses, inhibited in normal subjects, are more prevalent in dementia. Anomic aphasics show a pattern of word associations similar to that of subjects with mild dementia. Broca's aphasics, while making fewer paradigmatic associations than normals, retain enough self-monitoring mechanisms so that few idiosyncratic and perseverative responses are made while more null responses occur. Wernicke's aphasics show a marked shift away from a paradigmatic word association strategy, possibly due to an inability to access semantic markers or a true loss of these markers. Metalinguistic deficits (i.e., a failure to adopt an appropriate strategy) may also contribute to this shift away from paradigmatic associations. Furthermore, a disruption of self-monitoring mechanisms in Wernicke's aphasia leads to an increase in perseverative and idiosyncratic responses.     

Event-related potentials in phonological matching tasks

Two experiments investigated Event-Related Potentials (ERPs) in matching tasks. In Experiment 1 subjects judged, in separate conditions, whether two words rhymed or were written in the same case. The CNV developing between the two words was larger in the latter task compared to the former at the right temporal site. In the rhyme judgment task, an increased late negativity differentiated the ERPs to nonrhyming words from those that rhymed with the previously presented word. This difference was maximal at the midline and over the right hemisphere. Experiment 2 further investigated ERPs in the rhyme judgment task, increasing memory demands with an extended interstimulus interval (ISI) and varying the number of items subjects had to hold in memory during this period (one vs. three). Irrespective of memory load, CNVs during the ISI were more negative from the left hemisphere, and the ERPs to the rhyming and nonrhyming words showed the same differences as in Experiment 1. The CNV asymmetries are interpreted as being associated with the engagement of lateralized short-term memory processes. The rhyme/nonrhyme differences are possibly related to the “N400” component elicited by semantically incongruous words. Possible reasons for their scalp distribution are discussed.     

Transfer of conditioned inhibition across different aversive reinforcers in the rat

Three experiments using a conditioned suppression procedure in rats assessed transfer of conditioned inhibition across different aversive reinforcers. Experiment 1, using shock and car horn blast as reinforcers, showed that a noise negatively correlated with 0.7-mA shock between sessions attenuated suppression of lever pressing elicited by the signals for 0.7-mA shock and 110-db horn blast. Similarly, when the noise signaled the omission of horn blast, it attenuated suppression elicited by the signals for horn blast and shock. Experiment 2, using the same procedure, replicated transfer of conditioned inhibition from shock to horn found in Experiment 1, and indicated that such effects should be attributed to associative factors. Experiment 3, using the conditioned inhibition paradigm and different chambers during training and testing, replicated transfer from horn to shock and indicated that transfer cannot be attributed to multiple-background-reinforcer associations established during inhibitory training. The results of these experiments have implications for theories of conditioned inhibition.     

Response latency and response accuracy as measures of memory

The relationship is examined between response accuracy and response latency as measures of memory, and questions are raised concerning the value of the unidimensionality assumption often invoked in theories of memory. Three paired-associate experiments investigated the effects of the length of the retention interval, the kind of processing during incidental learning, and the number of study versus test trials during intentional learning. The findings, together with a review of selected studies in the literature, support three conclusions: (1) Latency of correct recall is not necessarily more sensitive than accuracy, (2) accuracy and latency of correct recall measure different aspects of memory, and (3) latency of correct recall and latency of incorrect recall measure different aspects of memory. The available data disconfirm the idea that any unidimensional construct (such as strength or the amount of information in memory) underlies memory performance. An explanation is offered that emphasizes the distinction between encoding and retrieval processes.     

The role of plausibility in influencing environmental attributions

The aim of the study was to examine how plausibility influences attributions about the cause of perceived arousal. Subjects watched one of three arousing (humorous, sexual, aggressive) or a nonarousing televised program under conditions of appropriate or inappropriate interpersonal spacing. The subjects then completed a questionnaire indicating how crowded they felt and rating the movie on a number of dimensions. The results indicated that under close interpersonal distances, subjects felt less crowded while watching the arousing movies than while viewing the nonarousing movie. There were no differences in the experience of crowding between the movie conditions under the far interpersonal distance conditions. In addition, subjects rated the arousing movies as more arousing under close as opposed to far interpersonal distance conditions. Further, the humorous movie was viewed as more funny, and the violent movie was rated more violent under the close as opposed to the far conditions. Finally, there was a tendency to enjoy the arousing movies more under the close conditions, while the reverse effect was found for the nonarousing movie. It was argued that the arousing movies reduced the experience of crowding under close interpersonal conditions because subjects attributed their arousal to the movies rather than to the spatial restrictions. It was further suggested that the results showed that individuals will attribute their arousal to salient stimuli in their environment that could plausibly be sources of arousal. The results not only offer support for an attribution model of crowding, but they also show that depending on the individual's attribution, spatial conditions that can give rise to crowding may increase enjoyment of events in the environment.     

Surface form and memory in question answering

Speakers tend to repeat materials from previous talk. This tendency is experimentally established and manipulated in various question-answering situations. It is shown that a question's surface form can affect the format of the answer given, even if this form has little semantic or conversational consequence, as in the pair Q: (At) what time do you close. A: “(At)five o'clock.” Answerers tend to match the utterance to the prepositional (nonprepositional) form of the question. This “correspondence effect” may diminish or disappear when, following the question, additional verbal material is presented to the answerer. The experiments show that neither the articulatory buffer nor long-term memory is normally involved in this retention of recent speech. Retaining recent speech in working memory may fulfill a variety of functions for speaker and listener, among them the correct production and interpretation of surface anaphora. Reusing recent materials may, moreover, be more economical than regenerating speech anew from a semantic base, and thus contribute to fluency. But the realization of this strategy requires a production system in which linguistic formulation can take place relatively independent of, and parallel to, conceptual planning.     

Developmental differences in cognitive scanning and encoding of visual information

Report accuracy of horizontally arranged letter sequences was measured for second-grade children and adults using a tachistoscopic single report procedure. Results indicated age differences in both the amount of information encoded out of visual sensory store and in the magnitude of left-right visual field differences. However, large age differences in amount of encoded information were also present under conditions which served to reduce left-right visual-field asymmetries in report accuracy. These findings are discussed in terms of their implications for using a left-to-right cognitive trace scanning explanation to account for age differences in encoding efficiency.     

Capacity increase and chunking in the development of short-term memory

The possibility of an age-related increase in the capacity of the short-term store was examined in two short-term memory experiments, and an M-operator model was proposed to account for the data. In the first experiment, lists of 8, 10, and 12 consonants were presented to 10-, 12-, and 14-year-olds. Despite the fact that the amount of chunking was monitored and kept constant across ages, there was a definite developmental increase in short-term memory performance. The size of the increase corresponded to the prediction of Pascual-Leone's M-operator theory. An M-operator model was proposed to account for the relation between performance level and list length at each age, as well as the developmental increase. Predictions of adult performance were tested in a second experiment. Together the two experiments show that an important part of short-term memory development can be explained as a growth in short-term store capacity.