The unimportance of explicit spatial information in serial recall of visually presented lists

The superiority of auditory over visual presentation in short-term serial recall may be due to the fact that typically only temporal cues to order have been provided in the two modalities. Auditory information is usually ordered along a temporal continuum, whereas visual information is ordered spatially, as well. It is therefore possible that recall following visual presentation may benefit from spatial cues to order. Subjects were tested for serial recall of letter-sequences presented visually either with or without explicit spatial cues to order. No effect of any kind was found, a result which suggests (a) that spatial information is not utilized when it is redundant with temporal information and (b) that the auditory-visual difference would not be modified by the presence of explicit spatial cues to order.     

Two modality effects in verbal short-term memory: Evidence from sentence recall

This paper investigates the mechanisms underlying the standard modality effect (i.e., better recall performance for auditorily presented than for visually presented materials), and the modality congruency effect (i.e., better memory performance if the mode of recall and presentation are congruent rather than incongruent). We tested the assumption that the standard modality effect is restricted to the most recent word(s) of the sentences but occurs in both verbatim and gist recall (Experiments 1 and 2), whereas the modality congruency effect should be evident for the rest of the sentence when using verbatim recall (Experiment 3) but not when using gist recall (Experiment 4). All experiments used the Potter-Lombardi intrusion paradigm. When the target word was the most recent word of the sentence, a standard modality effect was found with both verbatim recall and gist recall. When the target word was included in the middle of the sentences, a modality congruency effect was found with verbatim recall but not with gist recall.     

Retroactive effects of irrelevant speech on serial recall from short-term memory

The authors report 5 serial-recall experiments. In 4 of the 5 experiments, they show that irrelevant sound (IS) has a retroactive effect on material already in memory. In Experiment 1, IS presented during a filled retention interval had a reliable effect on list recall. Four further experiments, 3 of which used retroactive IS, showed that IS continued to-have an effect on recall following a long, filled retention interval. Articulatory suppression during visual input was found to abolish the long-lasting, retroactive effect of IS, supporting the idea that IS affects the phonological-loop component of short-term memory. IS also, therefore, seems to affect a longer term memory system with which the loop interacts.     

Immediate and delayed recall of visually presented sentences: evidence for the involvement of phonological information

The lure intrusion effect refers to the observation that lexical priming affects recall of sentences. This effect is taken as evidence against the contribution of surface information, even with immediate sentence recall. Recently, Rummer and Engelkamp (2003a) demonstrated that this effect, which is usually observed under rapid serial visual presentation (RSVP), does not appear under immediate recall of auditorily presented sentences. This finding indicates that surface information (i.e., phonological or acoustic-sensory information) can contribute to immediate sentence recall. So far, however, the findings do not allow for a decision on whether phonological and/or acoustic-sensory information is used in immediate sentence recall. In order to dissociate the two kinds of surface information, an experiment was conducted in which immediate and delayed recall were tested for sentences that were visually presented for a longer period of time than in RSVP. This kind of presentation should support phonological representations, but does not allow for acoustic-sensory representations. The findings showed a smaller intrusion effect for immediate than for delayed recall. This indicates that, if available, phonological information is involved in immediate sentence recall thereby reducing the lure intrusion effect. Furthermore, the findings support the assumption that the phonological trace provided via RSVP reading is weaker than in normal reading.     

Multiple roles for time in short-term memory: evidence from serial recall of order and timing

Three experiments are reported that examine the relationship between short-term memory for time and order information, and the more specific claim that order memory is driven by a timing signal. Participants were presented with digits spaced irregularly in time and postcued (Experiments 1 and 2) or precued (Experiment 3) to recall the order or timing of the digits. The primary results of interest were as follows: (a) Instructing participants to group lists had similar effects on serial and timing recall in inducing a pause in recall between suggested groups; (b) the timing of recall was predicted by the timing of the input lists in both serial recall and timing recall; and (c) when the recall task was precued, there was a tendency for temporally isolated items to be more accurately recalled than temporally crowded items. The results place constraints on models of serial recall that assume a timing signal generates positional representations and suggest an additional role for information about individual durations in short-term memory.     

Probe recall and short-term memory: Some evidence for nonlinear search strategies

Memory & Cognition - The subjects saw sequences of three, five, or seven digits. A subsequent probe test signaled subjects to respond with the item that had followed (forward probe) or preceded...     

Cue-dependent effects in recall of categorized lists

Noncued and cued recall of categorized lists are similar in a number of ways: They show the same rate of gain in item recall with increasing category size; they both produce serial position effects within categories; and they both show a “some-or-none” pattern of with-category recall frequency. Cued and noncued recall differ in other respects: There is a great improvement in item and in category recall attendant on the provision of cues, and only noncued recall displays a list position effect. The points of similarity are taken to indicate that both cued and noncued recall measure the same underlying processes. The points of differences suggest the utility of cueing procedures in identifying the origin of characteristics of recall, according to the principle that any feature of noncued recall that is altered by provision of cues must originate in the retrieval process; features resistant to such modification represent encoding or storage effects.     

Recognition and recall in short-term memory

A signal detection analysis of confidence judgments in short-term memory was used to investigate the difference in the amount of information required in memory for recognition and recall. In yoked recognition and recall experiments, subjects learned lists of five paired-associates and were probe-tested for one of them either by a recall or yes-no recognition procedure. This method permitted examination of the effect of serial position on the obtained differences in information in memory.     

Context in verbal short-term memory

We tested the hypothesis that stimulus-related contextual information that is incidental to task demands-an episodic code-is automatically, obligatorily encoded and stored as a part of short-term memory (STM) representations. Four experiments employed a running span task to investigate the effects of manipulating two types of contextual information: stimulus grouping and color. Three experiments established that grouping context effects are sensitive neither to volitional control nor to task difficulty and that they generalize across testing procedures (yes/no recognition and immediate serial recall). A fourth experiment demonstrated an effect of manipulating the congruity of the color of stimuli between study and test. These demonstrations of the robustness and generality of context effects in STM are consistent with the predictions of the episodic coding model of STM.     

False memory following rapidly presented lists: the element of surprise

This article examines a false memory phenomenon, the Deese-Roediger-McDermott (DRM) effect, consisting of high false alarms for a prototype word (e.g., SLEEP) following a study list consisting of its associates (NIGHT, DREAM, etc.). This false recognition is thought to occur because prototypes, although not presented within a study list, are highly activated by their semantic association with words that are in the list. The authors present an alternative explanation of the effect, based on the discrepancy-attribution hypothesis. According to that account, false (and true) familiarity results when a comparison between expectations and outcomes within a processing episode causes surprise. Experiment 1 replicates the DRM effect. Experiment 2 shows that a similar effect can occur when participants are shown lists of unrelated words and are then surprised by a recognition target. Experiments 3 and 4 show that the DRM effect itself is abolished when participants are prevented from being surprised by prototypes presented as recognition targets. It is proposed that the DRM effect is best understood through the principles of construction, evaluation, and attribution.     

Gummed-up memory: Chewing gum impairs short-term recall

Several studies have suggested that short-term memory is generally improved by chewing gum. However, we report the first studies to show that chewing gum impairs short-term memory for both item order and item identity. Experiment 1 showed that chewing gum reduces serial recall of letter lists. Experiment 2 indicated that chewing does not simply disrupt vocal–articulatory planning required for order retention: Chewing equally impairs a matched task that required retention of list item identity. Experiment 3 demonstrated that manual tapping produces a similar pattern of impairment to that of chewing gum. These results clearly qualify the assertion that chewing gum improves short-term memory. They also pose a problem for short-term memory theories asserting that forgetting is based on domain-specific interference given that chewing does not interfere with verbal memory any more than tapping. It is suggested that tapping and chewing reduce the general capacity to process sequences.     

Cuing effects in short-term recall

Past research indicates that short-term memory can be immune to the effects of proactive interference (PI). Past research also indicates that immunity to PI is found only in those circumstances where phonemic representations of to-be-remembered items are present and provide discriminative information. The first three experiments demonstrate the existence of a further boundary condition. PI is observed only if interfering and target items are subsumed by the same cue. This finding suggests that short-term recall, like long-term recall, is cue dependent. Cuing effects are further explored in two experiments that manipulate category dominance. The finding that category dominance effects parallel PI effects strongly suggests that retrieval cues play a critical role in short-term recall.     

Division of attention: Age differences on a visually presented memory task

Young and old adults were compared in their efficiency of remembering concurrently presented series of letters and digits in three separate experiments. Instructions and payoffs to vary attentional emphasis across the two types of material in different conditions allowed the examination of attention-operating characteristics in the two age groups. Strategy-independent measures derived from these attention-operating characteristics revealed that older adults exhibited greater performance deficits than young adults when dividing their attention between the two tasks, even though dual-task difficulty was individually adjusted for each subject. It was concluded that either the total amount of attention available for distribution or the efficiency of its allocation decreased with age even though the ability to vary one’s attention between concurrent tasks in response to instructions and payoffs remained intact.     

Effect of skill level on recall of visually presented patterns of musical notes

Expertise effects in music were studied in a new task: the construction of mental representations from separate fragments. Groups of expert musicians and non-musicians were asked to recall note patterns presented visually note by note. Skill-level, musical well-formedness of the note patterns and presentation mode were varied. The musicians recalled note patterns better than the non-musicians, even though the presentation was visual and successive. Furthermore, only musicians' performance was affected by musical well-formedness of the note patterns when visual gestalt properties, verbal rehearsability, and familiarity of the stimuli were controlled. Musicians were also able to use letter names referring to notes as efficiently as visual notes, which indicates that the better recall of musicians cannot be explained by perceptual visual chunking. These results and the effect of skill level on the distribution of recall errors indicate that the ability to chunk incoming information into meaningful units does not require that complete familiar patterns are accessible to encoding processes, yet previous knowledge stored in long-term memory affects representation construction in working memory. The present method offers a new reliable tool, and its implications to the research on construction of representations and musical imagery are discussed.     

Spacing and lag effects in free recall of pure lists

Repeating list items leads to better recall when the repetitions are separated by several unique items than when they are presented successively; thespacing effect refers to improved recall for spaced versus successive repetition (lag > 0 vs. lag = 0); thelag effect refers to improved recall for long lags versus short lags. Previous demonstrations of the lag effect have utilized lists containing a mixture of items with varying degrees of spacing. Because differential rehearsal of items in mixed lists may exaggerate any effects of spacing, it is important to demonstrate these effects in pure lists. As in Toppino and Schneider (1999), we found an overall advantage for recall of spaced lists. We further report the first demonstration of a lag effect in pure lists, with significantly better recall for lists with widely spaced repetitions than for those with moderately spaced repetitions.     

Single-probe serial position recall: evidence of modularity for olfactory, visual, and auditory short-term memory

The present study examined and compared order memory for a list of sequentially presented odours, unfamiliar faces, and pure tones. Employing single-probe serial position recall and following a correction for a response bias, qualitatively different serial position functions were observed across stimuli. Participants demonstrated an ability to perform absolute order memory judgments for odours. Furthermore, odours produced an absence of serial position effects, unfamiliar faces produced both primacy and recency, and pure tones produced recency but not primacy. Such a finding is contrary to the proposal by Ward, Avons, and Melling (2005) that the serial position function is task, rather than modality, dependent. In contrast, the observed functions support a modular conceptualization of short-term memory (e.g., Andrade & Donaldson, 2007; Baddeley & Hitch, 1974), whereby separate modality-specific memorial systems operate. An alternative amodal interpretation is also discussed wherein serial position function disparities are accommodated via differences in the psychological distinctiveness of stimuli (Hay, Smyth, Hitch, & Horton, 2007).     

Short-term retention of visually presented stimuli: some evidence of visual encoding.

Subjects saw two visual stimuli on each trial, separated by an interval ranging from 0 to 8 sec. Each stimulus was composed of a subset of the dots of a 7 × 5 dot matrix. In particular, it was a composite of two patterns, one of which formed a capital English letter and the other of which was an arrangement formed by 8 randomly selected dots. The task was to decide as quickly as possible whether the two stimuli contained the same letter. Under one condition (correlated noise) the same noise pattern was used with both letters; thus the decision as to whether the letters were the same could be based on a test of congruence of the two stimuli, noise and all. Under another condition (uncorrelated noise) the noise patterns differed, assuring that the composite patterns differed, and thus precluding congruence testing as an adequate way to determine whether the two letters were the same. Performance was better (RTs and error rates were smaller) with the correlated noise than with the uncorrelated noise. The result was taken as evidence that visual information was retained in memory, and used to advantage, when the situation clearly warranted the direct comparison of visual patterns.     

Recall of short word lists presented visually at fast rates: Effects of phonological similarity and word length

Phonological similarity of visually presented list items impairs short-term serial recall. Lists of long words are also recalled less accurately than are lists of short words. These results have been attributed to phonological recoding and rehearsal. If subjects articulate irrelevant words during list presentation, both phonological similarity and word length effects are abolished. Experiments 1 and 2 examined effects of phonological similarity and recall instructions on recall of lists shown at fast rates (from one item per 0.114-0.50 sec), which might not permit phonological encoding and rehearsal. In Experiment 3, recall instructions and word length were manipulated using fast presentation rates. Both phonological similarity and word length effects were observed, and they were not dependent on recall instructions. Experiments 4 and 5 investigated the effects of irrelevant concurrent articulation on lists shown at fast rates. Both phonological similarity and word length effects were removed by concurrent articulation, as they were with slow presentation rates.