Stimulus information and stimulus interference in bisensory short-term memory

An attempt was made to determine if Ss’ strategy of retaining stimulus material changed under conditions of bisensory simultaneous stimulation when one of the two inputs was relevant information as opposed to interference. Thus in Group 1 Ss were stimulated bisensorily, attended to both inputs (information), but recalled only one input. Ss in Group 2 were stimulated bisensorily, attended to only one input, and recalled only that input (interference). It was found that S’s efficiency of recall was decreased in the information condition (Group 1) but strategy was not altered. In both groups, Ss performed similarly; performance was in turn similar to that observed in the typical bisensory situation, i.e., where both channels are recalled.     

Effects of density of noise field and delay on information-processing of patterned inputs.

The present paper extends current research on pattern recognition to investigate the effects of density of noise field and delay (off) times. The results indicate major effects due to density of the noise field, on time and off time. Recognition initially declined as the density of the interference increased, then subsequently leveled off at higher interference levels. The effect of density of noise field on recognition was not consistent across all levels of either on time or off time. There was a wide range of processing-ability among Ss. Some subjects were capable of high levels of performance for very fast input rates. There was a high degree of consistency among Ss in the relative difficulty of the letters.     

Interference in memory for multiple contexts

Remembering that an item occurred in several different lists is formulated here in terms of retrieval of corresponding list tags associated to the item. Therefore, associative interference should operate upon remembering the several list contexts in which an item appeared. Experimental Ss studied four (or five) overlapping lists of 16 words, sampled from a master set of 32 words, with a given word exemplifying one of the 2 4 (or 2s 5 ) possible sequences of appearances and nonappearances over the four (or five) lists. Later Ss rated from memory for each word and for each list whether that word had occurred in that list. After correcting for interlist generalization effects, indices of discriminative memory revealed strong proactive interference and weaker retroactive interference. Discriminative memory that an item occurred in a given list was poorer the more prior or more subsequent lists in which that item had also occurred. Thus, list differentiation appears explicable in terms of item-specific associative interference.     

Cognitive-behaviour therapy in the treatment of chronic, occupational pain of the upper limbs: a 2 yr follow-up.

Nineteen Ss who experienced chronic, occupational pain of the upper limbs and who had previously completed a programme of either individual or group cognitive-behaviour therapy were followed up 2 yr later. Significant improvements on measures of depression, anxiety, coping strategies and interference in daily living were found following treatment. Such improvements were not evident for the waiting list control Ss and no difference was found between group vs individual applications of therapy. A 2 yr follow-up, significant improvements from pre-treatment levels were evident for depression, coping strategies, significant other report of disability, self monitored pain and distress caused by pain. While there was generally little evidence of relapse, a significant decline from post-treatment levels was found for the individual therapy condition compared to the group therapy condition on measures of self monitored pain and interference caused by pain. Since post-treatment levels tended to be somewhat superior for the individual therapy condition, the overall finding at 2 yr follow-up was of minimal difference in outcome for group vs individual forms of cognitive-behaviour therapy. Despite improvements from pre-treatment levels, the vast majority of Ss still reported significant and distressing levels of pain at 2 yr follow-up.     

Using selective interference to investigate spatial memory representations

Two experiments used a selective interference procedure in an attempt to determine whether nonverbal visual stimuli were represented in memory in a verbal or spatial format. A spatial representation was clearly implicated. In both experiments, Ss were required to remember either the positions or the identities of seven target items in a 25-item array. During the retention interval for that information, Ss attempted to recognize schematic face or airplane photograph stimuli in a same-different memory task. Memory performance on one or both tasks was greatly impaired when the recall task involved position or spatial information, but was either much less or not at all affected by an identity or verbal information recall task. Because of the selective nature of the interference and on the basis of certain correlational evidence, the experimental results were also interpreted as providing support for the notion that verbal and spatial information are stored and processed in separate information-processing systems.     

Temporary suppression of visual processing in an RSVP task: an attentional blink? .

Through rapid serial visual presentation (RSVP), we asked Ss to identify a partially specified letter (target) and then to detect the presence or absence of a fully specified letter (probe). Whereas targets are accurately identified, probes are poorly detected when they are presented during a 270-ms interval beginning 180 ms after the target. Probes presented immediately after the target or later in the RSVP stream are accurately detected. This temporary reduction in probe detection was not found in conditions in which a brief blank interval followed the target or Ss were not required to identify the target. The data suggest that the presentation of stimuli after the target but before target-identification processes are complete produces interference at a letter-recognition stage. This interference may cause the temporary suppression of visual attention mechanisms observed in the present study.     

Effects of a contralateral interference tone on auditory recognition

The effects of a contralateral interference tone on identification of the frequency of a brief signal were investigated. The signal was a 20-reset sinusoid and was the same intensity as the 500-msec interference tone. Changes in frequency discrimination were measured as a function of the temporal intee, al between rdgnal and interference tone. Frequency discrimination was unaffected by the presence of a leading interference torte. However, the addition of a trailing interference tone produced a small (about 15%) decrement in performance relative to discriminability measured in quiet. In contrast to the data and supporting theory of Massaro (1970) percent correct identification did not vary appreciably with intertone interval. The present data suggest that interference effects previously obtained with untrained Os ;are greatly attenuated for well-practiced Ss     

Improving recall by recoding interfering material at the time of retrieval.

Our experiments demonstrate that interference of an interpolated list of items with recall of an original list can be substantially reduced by forming Ss just before testing how to reorganize and simplify the interpolated material. In Experiments 1 and 2, Ss better recalled an initial serial list of letters when informed at testing that an interpolated list spelled a certain phrase backward. Similarly, in Experiments 3 and 4, Ss better recalled an initial list of cities when told that the interpolated cities were also names of former U.S. presidents. Control experiments rule out several simple explanations. In contrast to an editing hypothesis, the postorganizing clue helped recall even when problems of list differentiation were minimized. Current memory models appear unable to explain this benefit of a postlearning clue that enables Ss to segregate the interpolated material from the to-be-remembered material.     

Learning to utilize information presented over two sensory channels

In three separate experiments, Ss were provided with auditory, visual, or simultaneous auditory and visual information in a classification task. Difficulty of classification was manipulated by varying the stimulus exposure duration. Consistent bisensory facilitation effects were noted for later trials, with interference evident on earlier trials. Exposure duration influenced rate and not amount of learning, with bisensory performance being most affected by duration. A transfer paradigm was used in Experiment III, and little if any transfer was noted between unisensory and bisensory stimulus conditions. It was concluded that Ss were extracting the most salient bisensory stimulus components from the auditory and visual modes of information into a unidimensional information configuration.     

Stroop interference in naming and verifying spatial locations

Two experiments are reported that were designed to assess effects of semantic similarity on naming and verification of spatial locations. In Experiment I, the wordsabove, below, left, andright occurred as distractors when Ss named the location of the word relative to a dot, or the location of a dot relative to the word. In Experiment II. the same dot-word displays were used, but Ss reported whether or not the word correctly specified its own location relative to the dot or the location of the dot relative to itself. The naming task showed some within-dimension facilitation and interference effects, most notably when Ss named the location occupied by the distractor word. The verification tasks showed quite substantial retardation of “no” responses when the word and location represented different values on either the horizontal or the vertical dimension.     

Beziehungen zwischen Interferenzneigung und psychologischer Refraktärzeit

Zusammenfassung Es wurden Beziehungen untersucht zwischen einem Persönlichkeitsmerkmal, der Interferenzneigung, wie sie im Stroop-Test gemessen wird, und der psychologischen Refraktärphase, welche die Geschwindigkeit der Informationsverarbeitung im Human Operator entscheidend bestimmt. 24 Vpn, von denen 12 eine hohe und 12 eine niedrige Interferenzneigung hatten, wurden in 8 verschiedenen Versuchsvariationen Refraktärzeitmessungen unterzogen. Es zeigte sich, daß Vpn mit hoher Interferenzneigung signifikant längere Refraktärzeiten aufwiesen als Vpn mit niedriger Interferenzneigung. Die Differenzen zwischen den Interferenzgruppen nahmen zu mit ansteigender Komplexität der Versuchssituation und waren am deutlichsten ausgeprägt in den Versuchssituationen, welche der im Stroop-Test gegebenen Situation am ähnlichsten waren. Diese Ergebnisse bestätigen unsere Hypothese, daß das Ausmaß der Interferenzneigung in Zusammenhang steht mit der Länge der Refraktärphase. Das Interferenzphänomen kann somit verstanden werden als Ausdruck persönlichkeitsspezifischer Differenzen in der Geschwindigkeit der Informationsverarbeitung.

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On the relation between interference proneness and psychological refractory period

Summary The described experiment investigated relations between a personality trait, the interference as measured by the Stroop-Test, and the psychological refractory period, a determining factor in the speed of information processing by humans. Of 24 Ss, half of which had a high half a low interference tendency, measurements of psychological refractory periods in 8 different experimental situations were made. Ss witha high interference tendency had significantly longer psychological refractory periods than Ss with a low interference tendency. The differences between the two experimental groups increased with rising complexity of the experimental situation and were most clearly outlined in those variations, which were most similar to the situation given in the Stroop-Test. These experimental data proove our hypothesis: that the amount of interference is correlated with the length of the psychological refractory period. Thus the phenomenon of interference may be interpreted as an expression of personality differences in the speed of information processing.

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Von der Philosophischen Fakultät der Freien Universität Berlin 1966 angenommene Dissertation.     

Is numerical comparison digital? Analogical and symbolic effects in two-digit number comparison

Do Ss compare multidigit numbers digit by digit (symbolic model) or do they compute the whole magnitude of the numbers before comparing them (holistic model)? In 4 experiments of timed 2-digit number comparisons with a fixed standard, the findings of Hinrichs, Yurko, and Hu (1981) were extended with French Ss. Reaction times (RTs) decreased with target-standard distance, with discontinuities at the boundaries of the standard's decade appearing only with standards 55 and 66 but not with 65. The data are compatible with the holistic model. A symbolic interference model that posits the simultaneous comparison of decades and units can also account for the results. To separate the 2 models, the decades and units digits of target numbers were presented asynchronously in Experiment 4. Contrary to the prediction of the interference model, presenting the units before the decades did not change the influence of units on RTs. Pros and cons of the holistic model are discussed.     

On the independence of judged frequencies for items presented in successive lists*

In an experiment examining retroactive interference effects in a frequency-judging task, all Ss were presented with a list of words occurring varying numbers of times according to either a massed- or distributed-practive (MP or DP) schedule. They were then asked to judge how often each word had occurred. Following this, Ss were given one of four types of second tasks a second list with different items followed by a frequency-judging task for that list (Condition New): a second list with items repeated from the first list but with different frequencies for each item, while either maintaining items as either MP or DP items (Condition Same) or switching MP items to DP, and vice versa (Condition Reverse): followed by a frequency-judging task for the second-list frequencies only: or a puzzle task for the amount of time required for second-list presentation and judgment in the other conditions (Condition None). Finally, all Ss were asked to recall List 1 frequencies, List 2 frequencies were less discriminable in Conditions Same and Reverse than in Condition New. Recall of List 1 frequencies, however, was not different for these three groups, but was poorer than in List 2 frequency judgments were not independent of List 1 frequencies.     

Visual detection as a function of attentional demand and perceptual system error

Attentional demands were varied in a two-alternative, forced-choice detection experiment. A bar indicator designated the target form in one condition and occurred in random locations in a second condition. Exposure durations necessary for predetermined single-form display HRs were determined for each of eight Ss to measure performance at different levels of perceptual system error. Forms differed in only a single feature. Detection was superior when the bar indicator designated the target form, and differences increased with increased display size. Evidence for interference in detection due to the presence of nontarget forms apart from noting requirements of such forms was found. Estimates of number of perceptual channels noted did not clearly differentiate serial from parallel processing models. It was concluded that display interference error and spatial selectivity influences are important determinants of detection accuracy.     

Single-trace fragility theory of memory dynamics

In single-trace fragility theory, forgetting is produced by two factors, time and interference. Memory traces are assumed to have two partially coupled dynamic properties, strength and fragility. Strength determines the probability of correct recall and recognition, while fragility determines the susceptibility of the trace to the time-decay process but not to the interference process. Consolidation is assumed to be a continual reduction in the fragility of the memory trace rather than any change in strength or availability. Decreasing fragility accounts for the continually decreasing forgetting rate, the temporal character of retrograde amnesia and recovery therefrom, and the type of internal clock necessary for nonassociative recency judgments. Data are presented to indicate that interference is independent of the interval between original and interpolated learning, that nonassociative recency discriminability approaches a limit at about 30 min, and that the decay rate of long-term retention in amnesic patients is the same as in normal Ss.     

Item concreteness vs spatial organization as predictors of visual imagery

The relative contributions of item concreteness and interitem spatial organization to recall processes were studied by attempting to induce modality-specific interference between recall and response. Separate groups of 12 Ss learned lists of items that varied in physical or referential visual characteristics. They later signaled information about them either vocally or via a visually guided response. Some ways of presenting lists for learning that are traditionally regarded as increasing reliance on mediating imagery were effective in generating conflict between recall and the visually guided response. This effectiveness was limited to presentation conditions and list types that introduced spatial organization into the stimulus material. The concreteness of individual items was not useful in predicting visual conflict.     

Mechanisms of aural encoding: VIII. Phonetic interference and context-sensitive coding in short-term memory

In previous experiments Ss were presented for ordered recall with sequences of five consonant phonemes paired with /a/ in which the middle three consonant phonemes shared the same manner of articulation (voiced, unvoiced, nasal), the same place of articulation (front, middle, back), or neither the same manner nor place of articulation (control sequences). Compared to performance in control sequences, the middle consonant phoneme was always more difficult to recall in manner of articulation sequences but not in place of articulation sequences. The results suggested that for these sequences consonant phonemes were not remembered in terms of their place of articulation. In the present experiment, sequences of consonant-vowel (CV) or vowel-consonant (VC) syllables were presented for recall in which each consonant phoneme was paired with a different vowel. When consonant phonemes in the different sequence types were presented for recall with different vowels, phonetic interference was observed for the middle consonant in place of articulation sequences as well as manner of articulation sequences, and the effect was observed in both CV and VC groups. It was suggested that vowels are encoded in short-term memory in terms of their place of articulation and that presenting consonant phonemes for recall with different vowels caused Ss to use this dimension to code consonant phonemes in short-term memory.     

Oral and visual presentation and production of original responses.

Verbal originality scores were obtained from Onomatopoeia and Images, Form 1B, given to 106 Ss aged 10 to 12 yr. and 94 Ss aged 16 to 19 yr. The older Ss scored significantly higher than the younger Ss with significant main effects for age, but not for method of word presentation. A significant interaction was found between word presentation method and age. Older Ss were more original with the oral presentation while the younger Ss performed approximately the same with both methods.     

Expanding the tactual field of view

Can tactual information be acquired simultaneously by several different fingers? Blind and sighted Ss were asked to scan vertical displays of braille (consisting of either one or two dots) with the index and middle fingers on each hand-using one, two, or four fingers at the same time. Stimuli were recognized most rapidly when the displays were scanned by two fingers on different hands and least rapidly when two fingers on the same hand were used; performance was similar with one finger and with four fingers. The results indicated some parallel perceptual processing of the inputs to the two hands and mutual interference in processing inputs from fingers on the same hand.     

Selective processing of threat cues in anxiety states: a replication

A replication of Mathews and MacLeod's (Behav. Res. Ther. 23, 563-569, 1985) study, using a modified Stroop task, confirmed that threat words selectively interfere with the colour-naming performance of generally anxious patients, compared with normal controls. Clearer evidence was obtained of a highly specific interference effect of threat words that were congruent with the predominant worries reported by anxious patients. However, there was no evidence of a subsequent recognition memory bias for the threat words in anxious Ss. These results are discussed in relation to findings from other recent experiments investigating attentional and memory biases for threat-related information in anxiety states, and their implications for cognitive theories of anxiety are considered.