The word frequency effect in lexical decision: Finding a frequency-based component

Subjects making lexical decisions are reliably faster in responding to high-frequency words than to low-frequency words. This is known as the word frequency effect. We wished to demonstrate that some portion of this effect was due to frequency differences between words rather than to other dimensions correlated with word frequency. Three groups of subjects (10 engineers, 10 nurses, and I0 law students) made lexical decisions about 720 items, half words and half nonwords, from six different categories (engineering, medical, low-frequency nontechnical, medium-frequency nontechnical, and two groups of high-frequency nontechnical). Results of two analyses of variance revealed a crossover interaction such that engineers were faster in responding to engineering words than to medical words, whereas nurses were faster in responding to medical words than to engineering words. The engineering and medical words were equally long and equally infrequent by standard word counts. We take this as support for a frequency-based component in the word frequency effect. The practical implications of this research for estimating the readability of technical text are discussed.     

Sensitivity to lexical denotation and connotation in brain-damaged patients: A double dissociation?

Sets of words can be grouped in terms of their denotation (cold and warm both refer literally to temperature) or in terms of their connotation (cold and warm connote remoteness and intimacy, respectively). To assess whether these two facets of meaning are dissociable, unilaterally left- and right-hemisphere-damaged patients were presented with word triads and asked to group together the two words that were closest in meaning. Right-hemisphere-damaged patients showed a preserved sensitivity to denotation, and a selective insensitivity to connotative facets of meanings. In contrast, left-hemisphere-damaged patients exhibited a preserved sensitivity to connotation as well as a selective insensitivity to denotative aspects of meanings. Inasmuch as normal control subjects displayed a flexible sensitivity to both denotative and connotative aspects of meaning, the results suggest that unilateral brain damage selectively curtails use of one or the other major aspect of word meaning.     

Taste-aversion retention: An animal experiment with implications for consummatory-aversion alcoholism treatments

Inquiries into the longevity of illness-induced aversions (TAs) in animals are relevant to consummatory-aversion (CA) treatments of human alcoholism. The range of nausea reactions that accompanied the relapses of some alcoholics who had acquired alcohol aversions during covertsensitization (verbal aversion) alcoholism treatment has implicated CA forgetting as one probable contributor to recidivism. CA forgetting is operationalized as aversion diminution during postconditioning periods in which Ss abstain from contact with the target substance. TAs of varying strengths were induced in groups of Sprague-Dawley rats that received low, medium or high doses of the illness-inducing drug cyclophosphamide following saccharin-solution ingestion. TA retention was assessed following saccharin-free intervals of 2–40 days. Each Ss' retention interval was followed by 30 days of two-bottle preference testing, thereby additionally permitting an assessment of TA extinction following differing degrees of TA forgetting. Low-dose Ss displayed moderate strength TAs that were forgotten within 20 days and that had little resistance to extinction when testing began shortly after conditioning. Medium-dose Ss displayed stronger TAs having greater resistance to both forgetting and extinction. Unlike these low- and medium-dose TAs, high-dose TAs were impervious to aversion degradation as a result of forgetting. This finding is interpreted as supporting the attempted induction of intense nausea during covert-sensitization and chemical aversion (emetic therapy) alcoholism treatment. Other related conditioning procedures that may contribute to effective treatment are also discussed.     

EMG waveform duration: A validation method for the surface electromyogram

The electromyogram (EMG) recorded with surface electrodes was examined using a triggered oscilloscope technique. When all but the high-amplitude waveforms in a given segment of activity were excluded from analysis, it was found that the duration of the remaining waveforms was specific to the muscle that produced them. That is, waveforms of a given duration were recorded whenever conventional indices-observable contraction, joint movement. needle recordings-showed activity in a specific muscle. This led to the suggestion that waveform duration might be used to validate the surface EMG. The suggestion. which is limited by the need to control posture and electrode placement, both of which may influence waveform duration, was illustrated in application to psychological research.     

Phantasms of the living and of the dead

Summary In this outline no attempt has been made to prove survival, nor even to cite all of the more convincing types of cases, but to present in organized form some of the classes of evidence gathered by psychical research. During the eighty-odd years of organized research in this field, instances have been attested of apparitions which indirectly suggest the survival of personality.This article is an excerpt from one which appeared in theJournal of the American Society for Psychical Research, January, 1945, and is reprinted by permission of the author.     

Two types of short-term visual storage

Seven-letter words were flashed repetitively at various durations above and below the recognition threshold for single flashes. One form of a short-term storage effect was studied by measuring the interstimulus interval between flashes at which S reported that the stimulus became phenomenally discontinuous in time. Storage times reached a maximum of about 300 msec in this task. A second form of storage effect was measured by decreasing the interstimulus interval until S could correctly recognize a repeated stimulus whose duration was below the single-flash recognition threshold; this effect extended to 900 msec in some cases. Each of these effects was reliably obtained for both rare and frequent words. Both forms of storage were increased by providing a dark rather than a lighted adapting field between presentations of the test stimulus. Implications for Information processing of brief displays are discussed.