Interference in memory for tonal pitch: Implications for a working-memory model

The degree of interference caused by different kinds of stimuli on memory for tonal pitch was studied. Musically trained and untrained subjects heard a sequence of two tones separated by an interval of 5 sec. The tones were either identical in pitch or differed by a semitone. Subjects had to decide whether the tones were identical or not. The interval was filled with tonal, verbal, or visual material under attended and unattended conditions. The results revealed clear group differences. Musically trained subjects' retention of the first test tone was only affected by the interposition of other tones. In contrast, the performance of musically untrained subjects was also affected by verbal and visual items. The findings are discussed in the framework of Baddeley's (1986) working-memory model.     

Effect of interpolated temporal activity on temporal short-term memory

The purpose of this research was to determine the retroactive interference effects of a single interpolated task (i.e., one temporal duration) on the retention of a criterion duration. This research is of interest because the mnemonic structure of temporal information of different durations is uncertain. Previous research has indicated that there might be a difference in structure for durations of 1 and 4 sec., although the results are inconsistent. Thus, two criterion durations of 1 and 4 sec. and five interpolated durations (i.e., 60%, 80%, 100%, 120%, and 140% of the duration of the criterion) were utilized under the method of reproduction. In addition, subjects were instructed to use either a counting strategy or none (referred to as conscious time estimation) to facilitate the retention of the temporal information. Recall was less variable when using a counting strategy than not and when estimating 1 sec. than 4 sec. However, there was no effect of interpolated activity when comparing performance across different interpolated conditions (no interpolated activity). Apparently, one interpolated duration is not sufficient to produce structural interference with a single criterion duration.     

Counting strategies and assimilation effects in short-term retention of temporal information

The purpose of the present research was to examine proactive interference in general and assimilation effects (i.e., shifts in constant error caused by prior responses) in particular, when subjects used covert counting to aid their retention of the temporal information. Visually presented durations of 1, 4, and 8 sec. were estimated by 18 subjects under the method of reproduction. Three retention intervals (i.e., immediate, 15, and 30 sec.) and three intertrial intervals (i.e., immediate, 15, and 30 sec.) were employed. Analysis of constant error provided no indication that proactive interference was operating in the retention of temporal information as there was no increase in error across trials, no increase in error for longer retention intervals, and no interaction between trials and retention intervals. Also, there was no change in variable error as the retention intervals lengthened for any temporal duration except for the 4-sec. criterion. Finally, the rate of counting (counting units/sec.) was different across the durations to be remembered. The major conclusion of the present research was that counting greatly facilitates retention of temporal information as compared to retention without such a time-aiding strategy.     

Duplex perception with musical stimuli

Duplex perception, a phenomenon previously demonstrated for speech stimuli, is demonstrated here for musical stimuli. In the first experiment, major and minor chords are produced by dichotic fusion of two simultaneous piano notes presented to one ear (perfect fifth) with a “natural” or “flat” single note presented to the opposite ear. Musically trained subjects perceive simultaneously both the single tone and a fused (major or minor) chord. The chords are labeled more consistently than the single notes, even though the fused chords differ solely in terms of the contralateral notes. In a second experiment, using pure tones in place of piano notes, other musically trained subjects individually exhibited categorical perception for either the fused chord or the single tones, but never for both types of stimuli. The duplex phenomenon is discussed in terms of its implications for its specific component modes of perception.     

Suppression effects on musical and verbal memory

Three experiments contrasted the effects of articulatory suppression on recognition memory for musical and verbal sequences. In Experiment 1, a standard/comparison task was employed, with digit or note sequences presented visually or auditorily while participants remained silent or produced intermittent verbal suppression (saying "the") or musical suppression (singing "la"). Both suppression types decreased performance by equivalent amounts, as compared with no suppression. Recognition accuracy was lower during suppression for visually presented digits than during that for auditorily presented digits (consistent with phonological loop predictions), whereas accuracy was equivalent for visually presented notes and auditory tones. When visual interference filled the retention interval in Experiment 2, performance with visually presented notes but not digits was impaired. Experiment 3 forced participants to translate visually presented music sequences by presenting comparison sequences auditorily. Suppression effects for visually presented music resembled those for digits only when the recognition task required sensory translation of cues.     

Development of strategies for recalling letter sequences

Kindergarten, second-grade, and fourth-grade children (6, 8, and 10 years of age, respectively) were asked to recall letter sequences on a task that required the use of: (a) a verbal strategy; (b) a positional strategy; or (c) either strategy. Additional trials, allowing either strategy, were interspersed among those requiring a verbal or positional strategy; strategy use was determined from performance on these interspersed trials. The results show that children at all grade levels attempted to use a task-appropriate strategy. Performance on the verbal task showed a more marked developmental increase than did performance on the positional task. A second experiment replicated the first with the interspersed trials removed. A third experiment was designed to determine whether letter names interfered with older children's efficient use of a positional strategy. Even with this source of interference removed, the developmental pattern of Experiments 1 and 2 was replicated. There was a Sex by Condition interaction in Experiments 2 and 3 which showed that males do better in the condition requiring a positional strategy, and females do better in the condition requiring a verbal strategy.     

Verbal coding and the elimination of Stroop interference in a matching task

Translational models of the Stroop effect (Virzi & Egeth, 1985) predict that Stroop interference can be eliminated if subjects can be induced to process target colors using a coding system separate from the coding system used to process distractors. This hypothesis was tested in two experiments. In the first experiment, we attempted to eliminate the need for subjects to translate target colors to verbal codes when responding to Stroop stimuli. Before responding to verbal incongruent color word distractors, subjects practiced matching colors to irregular shapes. It was expected that subjects would use nonverbal codes to mediate responding in this task. After practice, subjects continued the matching task in the presence of incongruent color words. Stroop interference persisted, contrary to predictions. Because subjects reported adopting verbal strategies to perform the matching task, Experiment 2 was designed to control the verbal coding strategies that subjects employed. Before responding to Stroop distractor stimuli, subjects in the nonsense name group practiced using nonsense names to mediate the matching of shapes to colors; subjects in the actual name group used actual color names to mediate performance in the matching task. When incongruent color word distractors were introduced, Stroop interference was eliminated for subjects in the nonsense name group, but persisted for subjects in the actual name group. The results are interpreted as consistent with an outcome conflict (Navon & Miller, 1987) or a modified translational model of the Stroop effect.     

Short-term retention of tactile stimulation

In three experiments subjects were required to reproduce after varying delays the locus of a tactile stimulation delivered to the upper-side of the arm. During the retention periods subjects either performed a subsidiary, arithmetic task or rested. Recall, as measured by accuracy in reproducing the locus of stimulation, decreased as a function of retention interval, asymptoting after approximately 5 s. Performance was poorer in the subsidiary task condition than in the rest condition; however, the effect of the subsidiary task appeared to be more on subject recall strategies than on rehearsal capacity. No evidence of proactive interference effects was found, and a decay interpretation of forgetting of discrete tactile stimuli in the short-term memory distractor paradigm was favoured.     

An analysis of passive memory in normal and mentally retarded persons

The differential short-term retention of normal and mentally retarded persons is often attributed to differences in strategic functioning. There is, however, evidence for memory differences between these groups on tasks which minimize cognitive strategies. Many of the passive memory studies have been plagued with methodological and interpretative difficulties. The present experiment was an attempt to avoid these problems and clarify the possibility of passive memory differences.It was necessary to equate initial learning and control for rehearsal to compare the passive memory of normal and retarded persons across short, rehearsal-free intevals. The retention intervals were filled with a tonal detection task intended to prevent rehearsal.CA matched normal and retarded adolescents were required to recall sequences of consonants after periods of 0,9, and 27 sec. of tonal detection. These subjects also performed the detection task without the recall requirement over the same intervals. Subjects were classified as rehearsers and nonrehearsers, depending upon variations in their tonal detection accuracy, or response times across the two conditions. The main result was that normal and retarded nonrehearsers showed equal forgetting over the retention intervals.     

Music-to-language transfer effect: may melodic ability improve learning of tonal languages by native nontonal speakers?

In tonal languages, as Mandarin Chinese and Thai, word meaning is partially determined by lexical tones. Previous studies suggest that lexical tones are processed by native listeners as linguistic information and not as pure tonal information. This study aims at verifying if, in nontonal languages speakers, the discrimination of lexical Mandarin tones varies in function of the melodic ability. Forty-six students with no previous experience of Mandarin or any other tonal language were presented with two short lists of spoken monosyllabic Mandarin words and invited to perform a same–different task trying to identify whether the variation were phonological or tonal. Main results show that subjects perform significantly better in identifying phonological variations rather than tonal ones and interestingly, the group with a high melodic ability (assessed by Wing subtest 3) shows a better performance exclusively in detecting tonal variations.     

Dual trace theory and the consolidation of long-term memory

Retention functions were determined for four Ss for recognition memory of letters at 14 different delays from 3 sec to 5 min and two levels of storage load (1 and 6 letter lists), the retention interval being filled with backward counting. Memory strength retention functions were fit extremely well by assuming that two traces, short-term memory and long-term memory, are operative in this type of memory task. Only the short-term memory trace appears to be present during the first 8 or 10 sec of the retention interval, and this short-term trace decays exponentially with a time constant in the vicinity of 10 sec. Long-term memory is subject to a consolidation process which does not begin until about 10 sec after the study period and which is substantially complete at about 30 sec after the study period. Storage load has a very large effect on the degree of acquisition (learning) for both short and long-term traces, but storage load appears to have only a moderate effect or no effect on the decay rate of the short-term trace. There is some suggestion that the duration of the consolidation phase is shortened by an increase in storage load.     

Octave generalization of specific interference effects in memory for tonal pitch

An experiment is described which demonstrates that certain highly specific disruptive effects in immediate memory for tonal pitch generalize across octaves. Pitch recognition was required after a retention interval during which six other tones were played. The effects of including in the interpolated sequence tones which were removed by exactly an octave from those which had already been demonstrated to produce disruption were investigated. Generalization of these interference effects was found to result both from tones which were displaced an octave higher and (to a lesser extent) from tones which were displaced an octave lower. It is concluded that the memory store that retains information concerning the pitch of ifidividual tones is bidimensional in nature, both “tone height” and “tone chroma” being represented.     

Expectancies generated by melodic intervals: Evaluation of principles of melodic implication in a melody-completion task

Bottom-up principles of melodic implication (Narmour, 1990) were evaluated in a melody-completion task. One hundred subjects (50 low training; 50 high training in music) were presented each of eight melodic intervals. For each interval, the subjects were asked to compose a short melody on a piano keyboard, treating the interval provided as the first two notes of the melody. For each melody, the first response—the note immediately following the initial interval—was analyzed. Multinomial log linear analyses were conducted to assess the extent to which responses could be predicted by Narmour’s (1990, 1992) bottom-up principles. Support was found for all of Narmour’s principles, and two additional predictors based on implied tonal structure. Responses of low- and high-training groups were similar.     

言语次级干扰任务对客体与空间信息保持的影响

通过3个行为实验,以44名大学生或研究生为被试,考察了言语次级干扰任务是否对不同言语命名难度的客体与空间工作记忆信息的保持产生选择性干扰。研究发现:无论记忆对象是言语命名困难的客体信息,还是言语命名容易的客体信息,无论探测刺激是图形形式,还是词语形式,言语次级干扰任务都对客体信息的保持产生选择性干扰;但言语次级干扰任务对空间信息保持的影响,在不同条件下则表现出不同的特点。实验结果表明客体工作记忆自动、强制性地使用言语编码和保持机制,而空间工作记忆信息的保持是否由言语编码参与则受到其他因素的影响。     

Effects of cuing on short-term retention of order information

In two experiments, subjects recalled one of two letter sequences following a digit-filled retention interval. Recall performance was increased by precues informing subjects which letter sequence would be tested, and the cuing advantage remained throughout 60-digit retention intervals. No improvement was found, however, for cues occurring after the letters but before the digits. The cuing effects were attributed to encoding, not rehearsal, processes and were explained by a version of the Estes perturbation model, which included a long-term storage component and a fixed perturbation probability.     

Influence of tonal context and timbral variation on perception of pitch

In this study, spectral timbre's effect on pitch perception is examined in varying contexts. In two experiments, subjects detected pitch deviations of tones differing in brightness in an isolated context in which they compared two tones, in a tone-series context in which they judged whether the last tone of a simple sequence was in or out of tune, and in a melodic context in which they determined whether the last note of familiar melodies was in or out of tune. Timbre influenced pitch judgments in all the conditions, but increasing tonal context allowed the subjects to extract pitch information more accurately. This appears to be due to two factors: (1) The presence of extra tones creates a stronger reference point from which to judge pitch, and (2) the melodies' tonal structure gives more cues that facilitate pitch extraction, even in the face of conflicting spectral information.     

Effects of encoding the perceptual features of pictures on memory.

Four experiments investigated whether manipulations of type of encoding affects the likelihood of remembering pictures' visual details and their names. Using an incidental learning procedures, subjects were led to make judgments about pictures' colors, spatial orientations, or appropriateness in a scene. The results indicate that the nature of the memory test influences the effectiveness of different encoding conditions. Recall and recognition of pictures' names were best after subjects judged scene encodings, second best after they judged orientation, and poorest after they judged color. However, the results for the recognition of pictures' visual details were quite different. Analyses of d' suggested that type of encoding task had no effect on memory for visual details, whereas analysis of Pr (hit rate minus false-alarm rate) suggested that memory for visual details was impaired by conceptual encoding (judging the appropriateness of a picture in a scene). The results of one experiment demonstrated that these findings were not produced by variation in distinctiveness of the encoding questions. This pattern of findings implies that conceptual encoding facilitates retention of the names of the pictures at the cost of some loss in the ability to retain specific visual details.     

Short-term forgetting without interference

In the 1st reported experiment, we demonstrate that auditory memory is robust over extended retention intervals (RIs) when listeners compare the timbre of complex tones, even when active or verbal rehearsal is difficult or impossible. Thus, our tones have an abstract timbre that resists verbal labeling, they differ across trials so that no "standard" comparison stimulus is built up, and the spectral change to be discriminated is very slight and therefore does not shift stimuli across verbal categories. Nonetheless, performance in this nonverbal immediate memory task was better at short (1-, 2-, or 4-s) than long (8-, 16-, or 32-s) RIs, an outcome predicted by temporal distinctiveness theory whereby at long RIs, tones are closer in time to tones on previous trials. We reject this account in the 2nd experiment, where we demonstrate that the ratio of RI to intertrial interval makes absolutely no difference to performance. We suggest that steady forgetting is consistent with a psychoacoustically derived conception of an auditory memory (the timbre memory model) that embodies time-based forgetting in the absence of feature-specific interference.     

The development of visual encoding and retention skills

The development of the ability to visually encode and maintain a visual stimulus was examined in a paradigm in which verbal encoding of the stimulus was prevented. The 8-, 12-, and 21-year-old subjects participated in a shadowing task during which they viewed a letter which was visually presented for 200 msec, 5 sec after the shadowing list began. On each trial subjects either reported the letter immediately after presentation or continued shadowing for 4 or 10 sec. Although results replicated those found in previous research using the paradigm, no age differences were found in recall accuracy, types of errors, or introspective reports describing perceived recall strategy. These findings suggest that even 8 year olds were able to employ a visual code and retain it for several seconds in a situation in which incentive to do so was provided.     

An empirical note on the role of verbal labels in motor short-term memory tasks

Previous studies of motor short-term memory have shown that when a criterion movement on a semicircular positioning task is accompanied by an appropriate verbal label (a clock-face position), recall of the movement is more accurate than when only the movement is presented. This increased accuracy could be due to either the additional spatial information provided by the label or enhanced retention of the movement information. These two alternatives cannot be distinguished on the basis of previous studies because the studies have not evaluated movement accuracy following presentation of the label alone. The present study employed such a condition in addition to the movement-only and movement-plus-label conditions to distinguish between the two hypotheses. In all conditions, subjects were asked to move to the criterion position after a retention interval of either 5 sec or 60 sec. Evidence indicated that subjects who received both the label and the movement tended to use the spatial information provided by the label at the 60-sec interval. The evidence did not indicate that the verbal label actually enhanced retention of the movement information.