Semantic mechanisms in paralexia

This study explores the effects of semantic constraints on the occurrence of paralexic responses in two patients who tend to produce semantic errors in reading aloud. In the first experiment, semantic constraints were provided by using words as proper names (e.g., “brown” vs. “Sam Brown”), and in the second by using short, highly familiar phrases to restrict the meaning of the target word (e.g., the polar bear; green with envy). These constraints were found to be effective in reducing the frequency of paralexic errors.     

Inferential reasoning in old age

Two experiments examined the effects of aging on the kind of inferential reasoning required in comprehending discourse. In Experiment 1 old subjects made more errors than young subjects in solving logical problems framed in everyday language. Unlike the young subjects they had more difficulty when the problems were spoken than when they were written. Experiment 2 revealed that old subjects are inefficient at extracting implicit information during reading; they fail to generate bridging inferences to supply missing information, so that comprehension is restricted to explicitly stated information. The results show that verbal reasoning ability is impaired in old age and that this affects language comprehension in both listening and reading although the deficit is more marked in listening.     

Combined stimulus control over time allocation in response-independent schedules

Rats were exposed to concurrent schedules in which reinforcers occurred independently of behavior. In Experiment 1, rats could control time spent in the following conditions: (1) a light, (2) white noise, and (3) the absence of both light and noise. Response-independent reinforcers occurred at the same rate during the light and the noise and at either a higher rate or not at all in the absence of both stimuli. In subsequent tests, the rats spent more time in a light and noise compound than in either light or noise alone after the absence of both stimuli had signaled no reinforcers. When the absence of both stimuli had signaled a higher rate of reinforcement, however, the rats typically spent less time in the compound than in light or noise alone. In Experiment 2, rats could control time spent in the presence of a light and of a buzzer. The reinforcement rate in the light was twice that in the buzzer. In a later test, the rats spent more time in a light and buzzer compound than in the buzzer, but less time in the compound than in the light. The results show that additive summation, suppressive summation, and stimulus averaging of time allocation occur and that response rate differences between training stimuli are not necessary for these phenomena.     

Young children's use of temporal and spatial order information in short-term memory

Encoding and retrieval of temporal and spatial order information was investigated in the free recall and probed recognition performance of 3-, 4-, 5-, and 6-year-olds. In both tasks, three line drawings of familiar objects were presented successively in different spatial locations, so that temporal order was not confounded with spatial order. Subjects of all ages revealed an organization for the stimulus display based on the temporal sequence of presentation. With increasing age, subjects began recall more often with the first item so as to take advantage of this sequential organization. In the probed recognition task, subjects were asked questions requiring the use of temporal or spatial order information. Performance by the older subjects indicated that information about temporal and spatial order could be simultaneously encoded. The results are discussed in terms of a context theory derived from Estes's hierarchical association model.     

Reading abilities of school-age stutterers

The reading abilities of 20 school-age stutterers and their matched normally fluent controls were assessed by means of the Woodcock Reading Mastery Tests. Results indicate that the reading abilities of school-age stutterers are not significantly different from those of school-age normals. Similarly, knowing whether a subject was classified as a stutterer or normally fluent speaker was of minimal assistance in predicting the subject's reading performance. These findings suggest that school-age stutterers' reading abilities are within normal limits. An individual stutterer, just like an individual normally fluent speaker, may exhibit “reading problems”; however, caution should be employed in extrapolating from one individual stutterer's reading performance to the reading abilities of all stutterers.     

Clustering by aphasics in free recall

Aphasic performance was compared to normal and left hemiplegic controls in the use of clustering to aid recall of a list of words in a multitrial free recall experiment. Use of clustering correlated with increased recall scores. Left hemiplegic performance was superior to aphasic and inferior to normal suggesting that the presence of brain damage decreased clustering but that this decrease was greater in the presence of aphasia. A second experiment examined the possibility of remediating aphasic clustering behavior by providing cues as a training device. Cues, which aided normals, did not benefit the majority of aphasics. Results are interpreted in terms of their relationship to cognitive functioning.     

Influence of aging on recovery from aphasia in polyglots

We analyzed patterns of recovery, according to the rules of Pitres [1895, Revue de Medecine (Paris), 15, 873–899] and Ribot (1881, Les Maladies de la Memoire, Paris: Libraire Germer Baillere et Cie, pp. 146–147), in polyglot aphasics divided into subgroups by age. The rule of Ribot did not apply predictably for any age group. Pitres' rule clearly applied, but only for the nonelderly groups. Aging and its concomitant deterioration of recent memory seem to influence patterns of recovery from aphasia in polyglots.