Picture-naming in aphasia

The distribution of picture-naming errors for Broca's aphasics (n = 9), Wernicke's aphasics (n = 9), conduction aphasics (n = 9), frontal anomics (n = 7), and posterior anomics (n = 9) was examined to determine the diagnostic power of error types in picture-naming. Negated responses were associated with Broca's aphasia, whole-part errors ("hose" for nozzle) were associated with frontal anomia, and poor phonemic cuing was associated with Wernicke's aphasia. In addition, the relative distribution of the three most prominent naming errors-phonemic errors, semantic errors, and multiword circumlocutions-tended to distinguish the two anomic subgroups from the other aphasia subgroups. Anomic aphasics produced the fewest phonemic errors and the most multiword circumlocutions; this pattern suggests minimal word-production difficulty in anomic aphasia relative to the other aphasia syndromes. Despite such group differences, the overall picture indicates that there is considerable similarity among aphasia syndromes in terms of picture-naming behavior.     

Reconstructive retrieval deficits in Broca's aphasia

Anterior aphasic patients' ability to utilize the phonemic and/or semantic features of verbal material for retention purposes was investigated. In the first experiment, patients were asked to either detect word repetitions, phoneme repetitions, or rhymes in a list of items. The aphasics performed well on word and phoneme repetition detection but below both normals and amnesic Korsakoffs on rhyme detection. In the second experiment the patients were instructed to analyze either the physical, phonemic, or semantic features of words they were later asked to recognize. Aphasics were differentially affected (as were normals) by these instructions: semantic feature analysis resulted in the best performance, followed by phonemic feature analysis. It was concluded that anterior aphasics can analyze, recirculate, and even store the phonemic features of words, but find difficulty in reconstructing the originally presented item from these features.     

Effects of sound frequency on behavioral and cardiac orienting in newborn and five-month-old infants

Alert newborn and 5-month-old infants' responsivity to variations in spectral composition of a rattle sound was examined. Each child received four stimulus conditions: low-, mid-, and high-frequency bandpass-filtered rattles and an unfiltered broadband rattle. Stimuli were played through a single loudspeaker laterally positioned, and head orientation and cardiac responses to sound were recorded. Compared to other stimuli, the low-frequency sound elicted less head turning in both age groups, with this effect exaggerated in younger infants. Head orientation toward the mid-frequency, high-frequency, and broadband stimuli did not differ with age. For all conditions, latency and duration of newborns' head turning was longer than that of 5-month-olds. Newborns responded with cardiac deceleration only on trials when they failed to turn. When head turns occurred, an acceleratory cardiac response was obtained. Five-month-olds responded with reliable cardiac deceleration irrespective of head turning toward the sound. Heart rate change did not vary as a function of frequency at either age, suggesting that all stimuli were equally effective in eliciting the infant's attention.     

Encoding specificity in the alcoholic Korsakoff patient

A previous attempt to improve amnesic Korsakoff patients' retention of individual words resulted in only moderate improvement and, then, only under restricted conditions. It appeared that this occurred because the patients “forget” the instructed analysis of the word as well as the word itself. Consequently, the two experiments reported here sought to provide feature (Experiment 1) or associated (Experiment 2) cues at both input and output. In this manner relatively good performance was obtained, but only when semantic cues were “strongly” associated to the target words. Implications for an encoding specificity interpretation are drawn from these results.     

The influence of various types of control on psychophysiological stress reactions

The influence of personal control on reactions to shock was found to differ not only as a function of the type of control, but also as a function of the combination of control conditions. For example, behavioral control in the presence of information (cognitive control) reduced stress, whereas behavioral control in the absence of information augmented stress. These results are discussed with regard to the appropriateness of two different models, a “substitutive” versus an “interactive” model, for understanding the effects of personal control.     

Speech timing of grammatical categories

A series of experiments was performed to determine how the duration of a word spoken in a sentence is influenced by: (1) the grammatical category to which it belongs, and (2) the position of the word in a constituent. Experiment I contained Noun-Verb homophones (e.g. “I saw the coach…” — noun; “I saw him coach…” — verb), in sentences matched for phonetic environment and stress pattern. Results support the notion that Nouns are longer than Verbs in typical sentences. Experiment II, however, demonstrated that the duration of Noun-Verb homophones in matched clause-final position is approximately equal. Experiment III contained transitive and intransitive Verbs in matched sentences. The results of Experiments II and III provided support for a lengthening account based on constituent-final position, while ruling out an account based on a debatable deletion site. Results of Experiment IV generalized the account of constituent-final lengthening for Nouns and Verbs to additional major categories, by comparing the duration of the phrase-initial Adjective two with the phrase-final Adverb too. Finally, Experiment V tested the distinction between minor and major categories. Results demonstrated that the Preposition to is shorter than the Adjective two by approximately 50 percent. Taken in sum, these findings indicate that it is sufficient to make a binary distinction between major and minor categories for purposes of a theory of speech timing and speech synthesis. Durational effects traditionally ascribed to differences within the class of major categories can be accounted for solely in terms of constituent boundaries, already required in the theory to account for three other classes of phenomena.     

Three conditions on conceptual naturalness

Human infants are predisposed to organize their experience in terms of certain concepts and not in terms of others. The favored concepts are called natural, the remainder, unnatural. A major problem in psychology is to state a principled distinction between the two kinds of concepts. Toward this end, the present paper offers three, formal necessary conditions on the naturalness of concepts. The conditions attempt to link the problem of naturalness to the distinctions between sense versus nonsense, simplicity versus complexity, and validity versus invalidity.     

Alcoholic Korsakoff patients' retrieval from semantic memory

Alcoholic Korsakoff patients' rate of retrieval from semantic memory was investigated. It was found that their rate of retrieval from “lexical” semantic memory was nearly normal, but their rate of retrieval from “conceptual” semantic memory was impaired. In addition, an attempt to “prime” their lexical semantic memory by requesting the same category to be searched on adjacent trials met with failure. It was concluded that Korsakoff patients' lexical storage is probably organized normally, but their conceptual organization is not. Parallels with these patients' episodic memory impairments are discussed and possible interactions between episodic and semantic memory are proposed.     

The functional equivalence of mental images and errors of movement.

Four experiments are reported demonstrating that mental images are functionally equivalent to physical errors of movement in producing changes in visual-motor coordination, at both central and peripheral levels of the visual-motor system. In the first experiment, subjects in one condition pointed at a target seen through laterally displacing prisms and were instructed to imagine pointing errors identical to those recorded previously for subjects in a separate condition who actually observed their pointing errors. Changes in pointing accuracy during adaptation procedures and visual-motor aftereffects following these procedures for subjects who imagined their errors were proportional to visual-motor shifts and aftereffects for subjects who observed their errors. In the second experiment, these same imagery instructions resulted in identical pointing shifts and aftereffects even in the case where prisms did not displace the target. The third experiment showed that when subjects believe that their mental images of pointing errors do not correspond to their actual pointing errors, pointing aftereffects result that are characteristic of the processing of error information at peripheral, but not central, levels of the visual motor system. The final experiment showed that when subjects do believe that their images of pointing errors correspond to actual pointing errors, but imagine the pointing movement itself in addition to their errors, pointing aftereffects result that are characteristic of the processing of error information at central, but not peripheral, levels of the visual-motor system. Contributions to visual-motor aftereffects from these two levels appear to be additive. Another significant result was that, in the imagery feedback conditions of each experiment, subjects who gave high ratings of vividness to their mental imagery showed the greatest magnitude of pointing aftereffects. These findings establish that mental images for errors of movement can produce stable visual-motor changes that cannot be accounted for simply by subjects' expectations regarding the actual consequences of their actions.     

Development of voice recognition: parallels with face recognition.

Encoding and subsequent recognition of unfamiliar voices was examined in children, aged 6 to 16, and in adults. Performance changed markedly with age, improving sharply between ages 6 and 10, with 10-year-olds approaching adult levels. After age 10 accuracy declined significantly but returned to the adult level by age 14. The course of development closely matches that recently documented for the ability to encode and recognize unfamiliar faces. Several parallels between voice recognition and face recognition are discussed.