Immediate serial recall of words and nonwords: Tests of the retrieval-based hypothesis

In two experiments, the immediate serial recall of lists of words or nonwords was investigated under quiet and articulatory suppression conditions. The results showed better item recall for words but better order recall for nonwords, as measured with proportion of order errors per item recalled. Articulatory suppression hindered the recall of item information for both types of lists and of order information for words. These results are interpreted in light of a retrieval account in which degraded phonological traces must undergo a reconstruction process calling on long-term knowledge of the tobe-remembered items. The minimal long-term representations for nonwords are thought to be responsible for their lower item recall and their better order recall. Under suppression, phonological representations are thought to be minimal, producing trace interpretation problems responsible for the greater number of item and order errors, relative to quiet conditions. The very low performance for nonwords under suppression is attributed to the combination of degraded phonological information and minimal long-term knowledge.     

Where's the ball? Two- and three-year-olds reason about unseen events

Children 2, 2 1/2, and 3 years of age engaged in a search task in which they opened 1 of 4 doors in an occluder to retrieve a ball that had been rolled behind the occluder. The correct door was determined by a partially visible wall placed behind the occluder that stopped the motion of the unseen ball. Only the oldest group of children was able to reliably choose the correct door. All children were able to retrieve a toy that had been hidden in the same apparatus if the toy was hidden from the front by opening a door. Analysis of the younger children's errors indicated that they did not search randomly but instead used a variety of strategies. The results are consistent with the Piagetian view that the ability to use representations to guide action develops slowly over the first years of life.     

Silent reading rate and memory span

This paper reports two experiments concerned with the form of the linear function relating memory span to pronunciation rate. Experiment 1 asked whether the intercept of the equation is attributable to an interaction between modality, word-length, and serial position. The results lead us to reject this possibility. Experiment 2 examined the shape of the span function for visual presentation of lists read aloud or silently. The results show that the intercept of the span function disappears for silent presentation but not for aloud presentation. The results are discussed in terms of a balance between two opposing effects of word-length.     

Redintegration and the Useful Lifetime of the Verbal Memory Representation

Factors affecting immediate serial recall of individual items can be classified according to whether they influence the degradation of the representation, or influence the ability to redintegrate a degraded representation. For recall of entire lists, factors can be classified according to whether or not they influence the rate at which items are recalled. We review experiments in order to classify the factors of serial position, word length, word frequency, and lexicality. We propose that the two classification systems coincide, at least for those factors whose classification is known for both schemes. We end by considering whether probability of recall of an entire list might be predicted from probability of recall of individual items.     

Developmental study of multiple memory stages in the cuttlefish, Sepia officinalis

The inhibition of predatory behavior observed during the "prawn-in-the-tube" procedure has been extensively used in studies of cuttlefish learning. The present study examines the effect of age on the conditioning of this response in the cuttlefish, Sepia officinalis. Data show that a significant increase in acquisition performance occurs between 15 and 21 days of age. The retention curves in 8- and 15-day-old cuttlefish show a monotonic memory process, presumably reflecting the presence of only short-term memory. In 21-day-old cuttlefish, there are two distinct processes which could be a labile short-term memory, and a subsequent intermediate memory. These mnesic systems seem to become more effective over the course of post-embryonic development. Moreover, the retention curves obtained in the oldest cuttlefish (30- and 90-day-old) bear a close resemblance to that observed in adults. These behavioral findings will allow further work on the cellular and molecular mechanisms of learning and memory in the cuttlefish.     

The Real-Time Processing of Sluiced Sentences

Ellipsis refers to an element that is absent from the input but whose meaning can nonetheless be recovered from context. In this cross-modal priming study, we examined the online processing of Sluicing, an ellipsis whose antecedent is an entire clause: The handyman threw a book to the programmer but I don’t know which book the handyman threw to the programmer_ellipsis. To understand such an elliptical construction, the listener arguably must ‘fill in’ the missing material (“the handyman threw___ to the programmer”) based on that which occurs in the antecedent clause. We aimed to determine the point in time in which reconstruction of the sluiced sentence is attempted and whether such a complex antecedent is re-accessed by the ellipsis. Out of the two antecedent constituents for which we probed, only the Object (programmer) was found active in the elliptical clause, confirming that an antecedent is attributed to the sluice in real time. Possible reasons for the non-observation of the Subject (handyman) are considered. We also suggest that ellipses are detected earlier in coordinated than subordinated sentences.     

Short‐term and working memory: Past,progress, and prospects

Abstract

The role of current personal experience in understanding of word meaning was investigated in a patient, WM, who suffers from semantic dementia. The study was prompted by the observation that WM, despite being severely impaired on formal tests of word comprehension and naming, retained a range of vocabulary pertaining to her daily life. If autobiographical experience has a general facilitatory effect, then this should affect which concepts are retained and which lost, but not influence the quality of that conceptual knowledge. Conversely, if personal autobiography has a direct role in investing concepts with meaning, then WM's understanding of nominal terms that she uses spontaneously in conversation ought not to be normal, but should be constrained by the autobiographical context in which she uses those terms. WM could define nouns and noun phrases drawn from her conversational vocabulary, but her definitions had a markedly autobiographical quality. Moreover, WM was extremely impaired in her ability to define new noun phrases, constructed by combining words from her conversational vocabulary (e.g. “dog licence”, constructed from “driving licence” and “dog” “oil field” constructed from “oil” and “field”). It was concluded that WM does not have normal conceptual understanding of nouns and noun phrases that she uses appropriately in conversation. Her understanding is narrow and autobiographically constrained. The findings, which suggest an interactive relationship between autobiographical and semantic memory, have implications for understanding of the progressive breakdown of semantic knowledge.     

Assessment of sensory substitution prosthesis potentialities in minimalist conditions of learning

Pattern recognition with a prosthesis substituting vision by audition was investigated. During 15 1‐hour sessions, nine blindfolded sighted subjects were trained to recognise 2D patterns by trial and error. In addition to a global assessment, recognition of pattern element nature (vertical bars, horizontal bars…), element size and element spatial arrangement were independently assessed for each pattern. Influence of experimental parameters (complexity level of patterns, exploration number of a pattern) on recognition was studied. Performances improved over sessions. As a rule, patterns element nature was less well recognised than element size and spatial arrangement. Experimental parameters influenced pattern recognition performance. Results are discussed in relation with auditory and visual perception as well as in the perspective to implement a learning protocol for future users of prosthesis. Copyright © 2006 John Wiley & Sons, Ltd.     

Duration discrimination of empty time intervals marked by intermodal pulses

In 1973, Rousseau and Kristofferson reported that short empty intermodal time intervals marked by a light flash and a brief tone were poorly discriminated by subjects, and that AT,5 was constant over a large range of durations. It led them to suggest that short intramodal empty intervals, marked by stimuli from the same sensory modality, might be handled by a “more efficient mechanism” to which intermodal intervals would not have access. Unfortunately, their study lacked the basic evidence needed to make a strong statement: no direct comparison between inter- and intramodal duration discrimination and no within-subject discrimination function were available. To clarify these two issues, three experiments were performed. The data indicate that intermodal time intervals are discriminated more poorly than intramodal ones, and that intermodal duration discrimination functions follow Weber’s law. Analysis of data from different experiments lead to the conclusion that inter- and intramodal intervals are timed by a common timekeeper and that intermodal intervals induce a large noise component in the timekeeping operation.