Further considerations regarding inhibitory processes, working memory, and cognitive aging

The present study explored the relationship between inhibitory processing (as indexed by identity negative priming in a letter-naming task), working memory, discourse processing, and cognitive aging effects. Consistent with several other recent reports, this study found evidence of intact inhibitory processing, as measured by negative priming, in older adults as well as younger adults. This intact negative priming occurred in conjunction with diminished working memory span and impaired memory in the discourse processing task in the same sample of older adults, further arguing against the likelihood that declines in these areas are caused by impairments in the inhibitory processes measured by negative priming. The implications of these results for theories of cognitive aging and possible reasons for inconsistent findings regarding negative priming effects among the elderly are discussed.     

Short-term memory in the pigeon with presentation time precisely controlled

Delayed matching-to-sample was studied in the pigeon using a procedure which precisely controlled the presentation time of the sample stimulus. Experiments 1 and 2 revealed that (a) accuracy of matching increased as a negatively accelerated function of presentation time, (b) accuracy declined when an interstimulus interval was introduced between successive presentations of the sample stimulus, and (c) the rate at which accurate matching was restored after an interstimulus interval was greatest when the initial presentation of the sample was short and the interval was long. It was concluded that a theory of STM based on the growth and decay of trace strength could account adequately for all of these findings. Experiment 3 studied trace interaction by presenting two sample stimuli first in succession and then simultaneously for choice. Predictions from trace competition theory about the specific lengths of presentation of these stimuli at which choice of the second stimulus should be 50% or deviate systematically below 50% were not supported. It appears that a recency mechanism in addition to competition is necessary to explain trace interaction effects.     

The role of noun imagery in the speed of processing the grammaticality of adjective-noun phrases

This experiment investigated speed of processing the grammaticality of phrases consisting of the adjective “one” or “two” followed by a singular or plural noun. The subject’s task was to press one of two keys, depending upon whether the phrase was grammatically correct or incorrect. There were eight types of phrases, formed by the factorial combinations of singular or plural adjectives, singular or plural nouns, and high or low noun imageD’. These served as within-subjects variables. Between-subjects variables were the factorial combinations of sex of subject, duration of stimulus phrase (.2 or 2.5 sec), and hand assigned to the correct-grammar key. A fourth between-subjects variable was whether or not the subject reported using an artificial phrase-scanning strategy to determine grammaticality. Correct grammar, singular noun form, high noun imagery, and reported use of the strategy all produced highly significant reductions in reaction times. Only 1% of the interactions were significant. A multistage serial processing model that could be based upon Sternberg’s additive factor paradigm or even Donders’ subtraction method was found to be highly successful in describing the results.     

Effects of noun imagery and awareness of the discriminative cue upon differential eyelid conditioning to grammatical and ungrammatical phrases

Two differential eyelid conditioning studies employed grammatically correct and incorrect adjective-noun phrases as conditioned stimuli. For different groups of subjects, the nouns were either high or low in imagery. The hypothesis that congruency between grammatical correctness and reinforcement consequences (i.e., the aversive stimulus contingent upon presence of incorrect rather than correct grammar) would facilitate conditioned discrimination was not supported, but the hypothesis that high noun imagery would facilitate differential response to syntax received strong support. Cognitive awareness of the syntactic discriminandum was also related to effective differential responding, as well as being implicated as a mediating mechanism in the imagery effects. Finally, performance was also significantly related to conditioned-response topography, with better conditioned discrimination by voluntary-form (V) than by conditioned-form (C) responders, and also evidence of more effective utilization of contingency awareness by Vs than by Cs.     

Studies in auditory timing: 1. Simple patterns

Listeners' accuracy in discriminating one temporal pattern from another was measured in three psychophysical experiments. When the standard pattern consisted of equally timed (isochronic) brief tones, whose interonset intervals (IOIs) were 50, 100, or 200 msec, the accuracy in detecting an asynchrony or deviation of one tone in the sequence was about as would be predicted from older research on the discrimination of single time intervals (6%-8% at an IOI of 200 msec, 11%-12% at an IOI of 100 msec, and almost 20% at an IOI of 50 msec). In a series of 6 or 10 tones, this accuracy was independent of position of delay for IOIs of 100 and 200 msec. At 50 msec, however, accuracy depended on position, being worst in initial positions and best in final positions. When one tone in a series of six has a frequency different from the others, there is some evidence (at IOI = 200 msec) that interval discrimination is relatively poorer for the tone with the different frequency. Similarly, even if all tones have the same frequency but one interval in the series is made twice as long as the others, temporal discrimination is poorer for the tones bordering the longer interval, although this result is dependent on tempo or IOI. Results with these temporally more complex patterns may be interpreted in part by applying the relative Weber ratio to the intervals before and after the delayed tone. Alternatively, these experiments may show the influence of accent on the temporal discrimination of individual tones.     

Severity of psychosocial stress and outcome of alcoholism treatment

We examined the relation between stressful life events and drinking outcome among 129 male alcoholics who had completed an alcohol treatment program. Life events were assessed for the year prior to treatment and for the 3 months after treatment and were rated on the Psychiatric Epidemiology Research Interview and the Contextual Rating System. Approximately 40% of the pretreatment stressors were found to be directly or indirectly related to alcohol use. When stressors related to drinking were excluded from consideration, we found that men who returned to drinking after treatment experienced more severe or highly threatening stress before their relapse than men who remained abstinent during the follow-up period. These data suggest that although less severe stress may not increase risk for relapse, acute severe stressors and highly threatening chronic difficulties may be associated with elevated relapse risk.     

Nonconscious goal pursuit: Acting in an explanatory vacuum

Nonconsciously activated goals and consciously set goals produce the same outcomes by engaging similar psychological processes (Bargh, 1990; Gollwitzer & Bargh, 2005). However, nonconscious and conscious goal pursuit may have different effects on subsequent affect if goal pursuit affords an explanation, as nonconscious goal pursuit occurs in an explanatory vacuum (i.e. cannot be readily attributed to the respective goal intention). We compared self-reported affect after nonconscious versus conscious goal pursuit that either violated or conformed to a prevailing social norm. When goal-directed behavior did not require an explanation (was norm-conforming), affective experiences did not differ after nonconscious and conscious goal pursuit. However, when goal-directed behavior required an explanation (was norm-violating), nonconscious goal pursuit induced more negative affect than conscious goal pursuit.