Biomedical subjects

D A Balota

Publications and source records attributed to D A Balota.

At least 37 records · Page 2Linked to original sources

PubMed1997

Generation effects and source memory in healthy older adults and in adults with dementia of the Alzheimer type.

Recognition and source memory were explored in healthy older adults, adults diagnosed with very mild dementia of the Alzheimer type (DAT), and adults diagnosed with mild DAT. Two sentence-completion tasks were used. In Task 1, half of the sentences were completed (clozed) by the participant, and half by the experimenter. In Task 2, half were participant clozed, and half were participant read (already clozed). Recognition of the cloze words and accuracy of categorizing them as participant generated or experimenter generated (Task 1) and participant generated or participant read (Task 2) were measured (source discrimination). Contrary to previous reports, the DAT groups showed the generation effect, that is, better recognition for participant-generated words than experimenter-generated words (Task 1) or read words (Task 2). Source discrimination was disproportionately impaired in the DAT groups.

Aged↗

PubMed1997

Semantic satiation in healthy young and older adults.

In four experiments, semantic satiation was investigated in young and old adults. In the first two experiments, subjects were repeatedly presented a word (e.g., DOG) and then were presented a pair of words (e.g., DOG-CAT or DOG-CHAIR) for a relatedness decision. The results of both experiments indicated that for the young adults, the relatedness effect (the difference between response latency on related and unrelated trials) decreased as a function of the number of times the satiated word was repeated, whereas for the older adults, there was no evidence of a decrease in the relatedness effect across repetitions of the satiated word. In the third experiment, we investigated whether phonological codes are also susceptible to satiation. This experiment was similar to the first two experiments with the exception that subjects made rhyme decisions (SAME-CLAIM VS. SAME-DIME) instead of semantic relatedness decisions. The results of this experiment did not yield any evidence of satiation for either the young adults or the older adults. The final experiment eliminated a simple decrease in attentional alertness or fatigue account of the semantic satiation effects found in the first two experiments. In this experiment, the repeated word was always unrelated to the pair of words presented for the relatedness decision. The results of this experiment did not yield any evidence of semantic satiation for either the young or the older adults. The discussion focuses on the mechanisms underlying semantic satiation and the implications of age-related changes in these mechanisms.

Adolescent↗

PubMed1996

A positron emission tomography study of the short-term maintenance of verbal information.

Positron emission tomography (PET) was used to investigate the functional brain anatomy associated with the short-term maintenance of linguistic information. Subjects were asked to retain five related words, unrelated words, or pseudowords silently for the duration of a 40 sec PET scan. When brain activity during these short-term maintenance tasks was compared with a visual fixation control task, increases were found bilaterally in the dorsolateral prefrontal cortex and cerebellum, and medially in the supplementary motor area. Furthermore, effects of stimulus condition and recall performance were found in the left frontal operculum. To investigate the role of articulatory systems in the maintenance of verbal information, regional activation was compared across the maintenance tasks and a covert articulation task (silent counting). The cerebellum was active in both task conditions, whereas activation in prefrontal regions was specific to the maintenance condition. Conversely, greater activation was found in a left middle insular region in the silent counting than in the maintenance tasks. Based on converging results in this and previous studies, dorsolateral prefrontal cortical areas appear to contribute to the maintenance of both verbal and nonverbal information, whereas left frontal opercular regions appear to be involved specifically in the rehearsal of verbal material. Contrary to results found in other studies of working memory, activation was not found in the inferior parietal cortex, suggesting that this area is involved in aspects of stimulus encoding and retrieval, which were minimized in the present study.

Adult↗

PubMed1996

Stroop performance in healthy younger and older adults and in individuals with dementia of the Alzheimer's type.

Components of the Stroop task were examined to investigate the role that inhibitory processes play in cognitive changes in healthy older adults and in individuals with dementia of the Alzheimer's type (DAT). Inhibitory breakdowns should result in an increase in Stroop interference. The results indicate that older adults show a disproportionate increase in interference compared with younger adults. DAT individuals show interference proportionate to older adults but a disproportionate increase in facilitation for congruent color-word trials, and an increased intrusion of word naming on incongruent color naming trials. An ex-Gaussian analysis of response time distributions indicated that the increased interference observed in older adults was due to an increase in the tail of the distribution. Application of the process dissociation analysis of the Stroop task (D.S. Lindsay & L.L. Jacoby, 1994) indicated that older adults showed increased word process estimates, whereas DAT individuals showed differences in both color and word process estimates. Taken together, the results are consistent with an inhibitory breakdown in normal aging and an accelerated breakdown in inhibition in DAT individuals.

Adolescent↗

PubMed1996

Summation of activation: evidence from multiple primes that converge and diverge within semantic memory.

Six experiments addressed the combinatorial influence of multiple related primes in naming, lexical decision and relatedness judgment performance. Primes either converged on a single semantic representation (e.g., LION-STRIPES-TIGER) or diverged onto distinct semantic representations (e.g., KIDNEY-PIANO-ORGAN). The facilitatory influence of 2 related primes was well predicted by the sum of the influences from the single-related-prime conditions (a) for both convergent and divergent primes, (b) in lexical-decision and naming, (c) across varying prime-target stimulus onset asynchronies, and (d) under target-degradation conditions that increased the priming effects. The relatedness-judgment task yielded an additive pattern of priming for convergent prime conditions; however, an underadditive pattern of priming was found for divergent prime conditions. Discussion focuses on the role of attentional systems that modulate the type of information used to perform a given task.

Adult↗

PubMed1996

Characteristics of associative learning in younger and older adults: evidence from an episodic priming paradigm.

Two experiments investigated age differences in the encoding of associative information during a speeded naming task. In both experiments, semantically unrelated prime-target word pairs were presented 4 times, in either massed or spaced fashion, during the learning phase. An immediate or delayed test trial was presented following the fourth presentation. In Experiment 1, participants named both the primes and the targets. Younger and older adults showed similar benefits when naming targets that were part of a consistent prime-target pairing compared with targets presented with different primes at each presentation. In Experiment 2, participants named only the target word. Younger adults showed a benefit for consistently paired words, whereas older adults showed no benefit for consistently paired words. The results of the test trials showed a greater benefit for massed repeated words than for spaced repeated words at the immediate test and a reversed pattern at the delayed test. This spacing by test delay interaction was evident in response latency in Experiment 1 and in cued recall performance in Experiment 2.

Adult↗

PubMed1995

Mental chronometry: beyond onset latencies in the lexical decision task.

Four experiments addressed the influence of variables on lexical decision performance after response initiation has occurred. In Experiment 1, participants made an arm movement in one direction for word trials and pressed a button with the other hand for nonword trials. The results indicated that word frequency not only modulated the speed to initiate the arm movement, but also modulated the acceleration and force of the movement after initiation. The results of Experiment 2 indicated that word frequency and stimulus degradation produced large and additive effects on response latency, accuracy, and the force of the response after initiation. In Experiments 3 and 4, participants made the same arbitrary speech response in a modified lexical decision task for both high- and low-frequency words. The results indicated that both the onset and duration of the speech response were modulated by word frequency. The results are viewed as most consistent with an enabled response model, wherein early operations can enable appropriate action systems before central decisions are made.

Adult↗

PubMed1994

Role of elaborative and perceptual integrative processes in perceptual-motor performance.

Three experiments address the dependence of both explicit and implicit memory performance on elaborative processes for a perceptual-motor task, pursuit rotor. Explicit memory performance was reflected by recognition of previously encountered pursuit rotor stimuli. Implicit memory performance (priming) was identified in Experiment 1 as an advantage in pursuit rotor performance for old stimuli that Ss failed to explicitly recognize. In Experiments 2 and 3, the types of strategies that Ss engaged in during training and test phases were manipulated. Results indicated that explicit memory performance depended on elaborative processes that emphasized which specific stimuli were encountered, whereas reliable implicit memory performance appeared only under a control no-instruction condition. Discussion focuses on attention to perceptual-integrative processes for priming.

Adolescent↗

PubMed1993

Implicit memory and the formation of new associations in nondemented Parkinson's disease individuals and individuals with senile dementia of the Alzheimer type: a serial reaction time (SRT) investigation.

Using the serial reaction time (SRT) task developed by Nissen and Bullemer (1987, Cognitive Psychology, 19, 1-32), implicit memory performance was examined in four groups of subjects: nondemented healthy aged individuals; nondemented Parkinson's disease individuals; very mildly demented senile dementia of the Alzheimer type (SDAT) individuals; and mildly demented SDAT individuals. The SRT task involved four blocks of a repeated 10-item keypress sequence that tapped general skill development along with a fifth block of a nonrepeated sequence that presumably reflected the impact of switching from a learned set of associations (developed during the first four blocks) to a novel sequence. The increase in response latency from the fourth repeated block to the fifth nonrepeated block was used as the reflection of implicit learning. The results revealed preserved implicit memory performance in the very mildly demented individuals compared to that of the age-matched control individuals. However, the mildly demented SDAT individuals and the nondemented Parkinson's disease individuals showed reliably less implicit learning, compared to the age-matched control individuals. Differences between the past studies using the SRT task to tap implicit memory performance in SDAT individuals and the present study are discussed in some detail. We conclude that nondemented Parkinson's disease individuals and mildly demented SDAT individuals produce some deficit in the formation of new associations in implicit memory, as measured by the SRT task.

Aged↗

PubMed1992

Automatic and attentional priming in young and older adults: reevaluation of the two-process model.

Three experiments addressed the distinction between automatic and attentional mechanisms underlying semantic priming effects by factorially crossing prime-target relatedness, expectancy, and SOA in a task (pronunciation) that minimized postlexical checking processes. Also, possible age-related (young vs. older adults) differences in the automatic and attentional mechanisms were addressed. Across all experiments there was evidence of a Relatedness x Expectancy x SOA interaction, which is inconsistent with the notion of independent automatic and attentional mechanisms in semantic priming and the notion of a self-encapsulated modular lexicon. The results also indicated age-related differences in the build-up of the expectancy effect across SOAs when the prime was visually available for only 200 ms, independently of the prime-target SOA (Experiments 1 and 3), but not when the prime was visually available throughout the SOA (Experiment 2).

Adolescent↗

PubMed1992

On the relation between feeling of knowing and lexical decision: persistent subthreshold activation or topic familiarity?

Experiment 1 replicated Yaniv and Meyer's (1987) finding that lexical decision and episodic recognition performance was better for words previously yielding high-accessibility levels (a combination of feeling-of-knowing and tip-of-the-tongue ratings) in comparison with those yielding low-accessibility levels in a rare word definition task. Experiment 2 yielded the same pattern even though lexical decisions preceded accessibility estimates by a full week. Experiment 3 dismissed the possibility that the Experiment 2 results may have been due to a long-term influence from the lexical decision task to the rare word judgment task. These results support a model in which Ss (a) retrieve topic familiarity information in making accessibility estimates in the rare word definition task and (b) use this information to modulate lexical decision performance.

Adult↗

PubMed1991

Semantic priming effects, lexical repetition effects, and contextual disambiguation effects in healthy aged individuals and individuals with senile dementia of the Alzheimer type.

An experiment is reported that addresses semantic priming effects, lexical repetition effects, and the influence of context on meaning selection for ambiguous words in 32 healthy aged individuals and 32 individuals with Senile Dementia of the Alzheimer Type (SDAT). On each of 232 trials, subjects pronounced each of three words. The four major conditions were concordant (music-organ-piano), discordant (kidney-organ-piano), neutral (ceiling-organ-piano), and unrelated (kidney-ceiling-piano). In order to address lexical repetition effects, target words were repeated across Blocks 1 and 2 but not in Block 3. Analyses of naming latencies indicated that semantic priming effects and lexical repetition effects were slightly larger in SDAT individuals than in healthy aged individuals. More importantly, healthy aged individuals produced normal selective access of the contextually biased meaning whereas SDAT individuals produced evidence consistent with nonselective meaning access. These results are discussed within both an attentional and a connectionist account of homograph disambiguation.

Aged↗

PubMed1990

Where are the effects of frequency in visual word recognition tasks? Right where we said they were! Comment on Monsell, Doyle, and Haggard (1989).

Balota and Chumbley's studies led them to conclude that category verification, lexical decision, and pronunciation tasks involve combinations of processes that cause them to produce differing estimates of the relation between word frequency and ease of lexical identification. Monsell, Doyle, and Haggard challenged Balota and Chumbley's empirical evidence and conclusions, provided empirical evidence to support their challenge, and presented an alternative theoretical position. We show that Monsell et al.'s experiments, analyses, and theoretical perspective do not result in conclusions about the role of word frequency in category verification, lexical decision, and pronunciation that differ from those of Balota and Chumbley.

Attention↗

PubMed1990

Suffix interference in the recall of linguistically coherent speech.

Four experiments are presented that address the stimulus suffix effect for linguistically coherent spoken materials. In Experiment 1, definitions of low-frequency words were presented for online written recall. Each definition was followed by a nonword speech suffix presented in the same voice as the definition, the same nonword presented in a different voice, or a tone. The results yielded a significant reduction in the recall of the terminal words of the definitions in the speech suffix conditions compared with the tone control. This general pattern was replicated in Experiment 2, in which subjects did not begin their recall until the suffix item or tone was presented, although the magnitude of the suffix effect was reduced in this experiment. In Experiment 3, sentences that were part of a cohesive story were presented for on-line recall. Here, the suffix effect was considerably reduced compared with the suffix effect found with the definitions presented in Experiments 1 and 2. This pattern was replicated in Experiment 4, in which subjects did not begin their recall of the story sentences until the speech suffix or tone was presented. Overall, the results suggest that auditory memory interference can take place for linguistically coherent speech, although the magnitude of the interference decreases as one increases the level of linguistic structure in the to-be-recalled materials. Implications of the present results for current models of natural language processing are discussed.

Adult↗

PubMed1989

Age-related differences in the impact of spacing, lag, and retention interval.

An experiment is reported that examines age-related differences in the lag effect and its relation to retention interval. A total of 30 young and 30 older adults received both once-presented pairs and twice-presented pairs that were tested in a continuous cued-recall paradigm either after a short retention interval (2 pairs intervening between the last presentation of a pair and its test) or a long retention interval (20 pairs intervening between the last presentation of a pair and its test). In addition, the twice-presented pairs were separated by either 0, 1, 4, 8, or 20 intervening pairs. The results replicated the interaction between retention interval and lag that has been reported by Glenberg (1976, Journal of Verbal Learning and Verbal Behavior, 15, 1-16). Furthermore, although the older adults performed considerably lower than the younger adults in overall recall performance, their data were remarkably similar to the younger adults in the patterning of means. A mathematical modeling procedure was used to fit the data to Estes' stimulus fluctuation model. The results of this modeling procedure suggest that, compared with younger adults, older adults (a) encode less contextual information at a given point in time and (b) have a slower rate of contextual fluctuation across time.

Adult↗

PubMed1989

Spreading activation in episodic memory: further evidence for age independence.

Seventy-two young (mean age = 25 years) and 72 old adults (mean age = 71 years) participated in an experiment that addressed the influence of episodic and semantic prime activation on speeded episodic recognition judgements. On each test block, subjects studied two paragraphs at their own pace to achieve a designated level of episodic recognition performance. Following the study period, subjects were presented a series of prime-target trials for speeded episodic recognition. The primes were either (a) episodically related to the target, (b) semantically related to the target, (c) episodically and semantically related to the target, or (d) episodically and semantically unrelated to the target. The stimulus onset asynchrony (SOA) between the primes and targets was either 200 msec, 600 msec, or 1000 msec to address age-related changes in the rate at which these different prime types influenced performance. The results indicated that, compared to young adults, the old adults (a) studied the paragraphs for a longer period of time, (b) responded to the targets more slowly, and (c) were less accurate in their episodic recognition decisions. Although there were these main effects of age, the young and old adults were influenced in a similar fashion by the different prime-target relationships and by the interactive influences of the prime-target relationships and SOA. Correlational analyses indicated that the pattern of priming effects was as similar across the two age groups as across two pseudo-groups that were matched on the age dimension. These results were viewed as further support for the notion that the characteristics of the spreading activation mechanism as reflected by prime-target manipulations are relatively stable across young and old adults.

Adolescent↗

PubMed1988

Age-related differences in lexical access, spreading activation, and simple pronunciation.

An experiment was conducted to address age-related differences in lexical access, spreading activation, and pronunciation. Both young and older adults participated in a delayed pronunciation task to trace the time course of lexical access and a semantic priming task to trace the time course of spreading activation. In the delayed pronunciation task, subjects were presented a word and then, after varying delays, were presented a cue to pronounce the word aloud. Older adults benefited considerably more from the preexposure to the word than did the younger adults, suggesting an age-related difference in lexical access time. In the semantic priming pronunciation task, semantic relatedness (related vs. neutral), strength of the relationship (high vs. low), and prime-target stimulus onset asynchrony (200 ms, 350 ms, 500 ms, 650 ms, and 800 ms) were factorially crossed with age to investigate age-related differences in the buildup of semantic activation across time. The results from this task indicated that the activation pattern of the older adults closely mimicked that of the younger adults. Finally, the results of both tasks indicated that older adults were slower at both their onset to pronounce and their actual production durations (i.e., from onset to offset) in the pronunciation task. The results were interpreted as suggesting that input and output processes are slowed with age, but that the basic retrieval mechanism of spreading activation is spared by age.

Adolescent↗

PubMed1986

Voice-specific information and the 20-second delayed-suffix effect.

Two experiments were conducted to investigate the nature of the delayed-suffix effect reported by Watkins and Todres (1980). In both experiments, subjects were presented lists of digits for serial recall. At the end of each list either a tone or a voice reading aloud the word go was presented. The voice was either in the same voice that read the digits or in a different voice. Past research has indicated that the tone control produces the least interference, followed by the different-voice suffix, which in turn produces less interference than the same-voice suffix. The results of both experiments indicated that when subjects were tested on immediate recall for the lists, the typical ordering of tone control, different-voice suffix, and same-voice suffix on recall at the last serial position was found. However, when there was a 20-s filled interval between the last list item and the suffix, there was only a difference between the tone control and the same- and different-voice suffixes with no difference between the latter two conditions. In addition, Experiment 2 failed to support a simple attentional account of the differential influence of voice in the immediate and delayed-recall conditions. The results are viewed as supporting a perceptual tuning mechanism in which perceptual specificity decreases with the passage of time.

Adolescent↗