The modality effect,sensory handicap,and compensatory functions

In the present study 84 subjects (48 normal, 24 deaf, and 12 blind subjects) participated in a free recall experiment. Modality of presentation (auditory, visual) as well as mode of response (oral, written) were manipulated as between-subjects variables. It was found that deaf subjects can compensate for their handicap in as much that written recall of visual short-term memory items was significantly better than for normal subjects. For oral recall of long-term memory positions the deaf performed worse than the normal hearing. The blind subjects' oral recall performance was on a par with the normal subjects' for written recall of auditory presented items, but the blind exhibited some signs of inferiority for the oral comparison. The output order data demonstrated that normal subjects recall visual items in a backward order and auditory items with a mixed strategy; the deaf exhibited mixed strategies and the blind displayed clear backward strategies. Neither output order nor recency-prerecency preference could account for the compensatory patterns. Finally, the task-dependent nature of the obtained data is discussed.     

Linguistic coding by deaf children in relation to beginning reading success

The coding of printed letters in a task of consonant recall was examined in relation to the level of success of prelingually and profoundly deaf children (median age 8.75 years) in beginning reading. As determined by recall errors, the deaf children who were classified as good readers appeared to use both speech and fingerspelling (manual) codes in short-term retention of printed letters. In contrast, deaf children classified as poor readers did not show influence of either of these linguistically based codes in recall. Thus, the success of deaf children in beginning reading, like that of hearing children, appears to be related to the ability to establish and make use of linguistically recoded representations of the language. Neither group showed evidence of dependence on visual cues for recall.     

Assessing the effect of lexical variables in backward recall

In a recent study, Bireta et al. (2010) suggested that when participants are required to recall lists of items in the reverse order, more attention is devoted to the recall of order at the expense of item information, leading to the abolition of item-based phenomena (the item and order trade-off hypothesis). In order to test the item and order trade-off hypothesis, we manipulated 4 lexical factors that are well known to influence item retention. The effects of word frequency, of lexicality, of semantic similarity, and of imageability were tested in forward and backward recall. All 4 phenomena were maintained in backward recall, which contradicts the item and order trade-off hypothesis. Instead, we suggest that backward recall might rely on semantic retrieval strategies.     

The associative learning of the deaf: The effects of word imagery and signability

In two experiments, deaf and hearing subjects learned paired associate lists in which rated visual imagery and signability (a measure of the ease with which a word can be represented as a gestural sign) were orthogonally varied. Visual presentation of three alternating study-recall trials resulted in significant positive effects of imagery for both deaf and hearing subjects, whereas signability facilitated recall only for deaf subjects. Examination of the relation between item attributes and reported learning strategy indicated that both deaf and hearing subjects used imaginal mediators more frequently for high-imagery than low-imagery pairs. A gestural sign strategy was reported almost exclusively by deaf subjects, particularly for high-signability pairs. These results suggest that an examination of the effects of sign language variables will contribute to an understanding of the qualitative differences in the associative learning of the deaf and hearing.     

Recall of order information by deaf signers: Phonetic coding in temporal order recall

To examine the claim that phonetic coding plays a special role in temporal order recall, deaf and hearing college students were tested on their recall of temporal and spatial order information at two delay intervals. The deaf subjects were all native signers of American Sign Language. The results indicated that both the deaf and hearing subjects used phonetic coding in short-term temporal recall, and visual coding in spatial recall. There was no evidence of manual or visual coding among either the hearing or the deaf subjects in the temporal order recall task. The use of phonetic coding for temporal recall is consistent with the hypothesis that recall of temporal order information is facilitated by a phonetic code.     

Effects of signability and imagery on word recall of deaf and hearing students

This study examined 40 deaf and 20 hearing students' free recall of visually presented words varied systematically with respect to signability (i.e., words that could be expressed by a single sign) and visual imagery. Half of the deaf subjects had deaf parents, while the other half had hearing parents. For deaf students, recall was better for words that had sign-language equivalents and high-imagery values. For the hearing students, recall was better for words with high-imagery values, but there was no effect of signability. Over-all, the hearing students recalled significantly more words than the deaf students in both immediate and delayed free-recall conditions. In immediate recall, deaf students with deaf parents reported using a sign-language coding strategy more frequently and recalled more words correctly than deaf students with hearing parents. Serial-position curves indicated several differences in patterns of recall among the groups. These results underline the importance of sign language in the memory and recall of deaf persons.     

Memory storage and retrieval within and across modalities in children

Twenty-four kindergarten and fourth grade children were asked to locate a display card which had been visually or verbally presented. A probe, which identified the card to be located, was presented verbally and visually equally often. The children's ability to recall the location of an item did not differ as a function of the modality to which the material was presented. Nor was recall significantly affected when the presentation modality differed from the probe modality, suggesting that children as young as 5 can cross these sensory modalities to retrieve material with no loss in accuracy. Serial position curves suggest that the verbal and visual material is not stored in a common intersensory store. The primacy effect is found to be stronger with visually presented material and the recency effect strongest with auditorily presented material. Probe modality did not influence the serial position curves.     

Memory and rehearsal characteristics of profoundly deaf children

This study examined whether a deficiency in spontaneous strategy use accounts for deaf children's verbal short-term memory performance. Various colors were presented for 3 s each, followed by a 15-s recall delay. The delay was either unfilled, or subjects were induced to rehearse or were prevented from rehearsing. Sixty-four deaf students from oral and total communication settings, 5 to 15 years of age, were tested. The spontaneous rehearsal of both deaf samples seemed to emerge later than the hearing sample's, and it was both inefficiently implemented and less effective in mediating recall than hearing children's. However, when rehearsal was prevented or was induced in all samples, the deaf recalled as well as, or better than, the hearing. Implications discussed include the need to compare both spontaneous and controlled strategy use in developmental memory studies, and the need to provide additional training for deaf children in the strategies of remembering, as opposed to the content material.     

Visual and phonological components of working memory in children

Previous studies have shown that young children's immediate memory for a short series of drawings of objects is mediated by a visual component of working memory, whereas older children rely chiefly upon a phonological component. Three experiments investigated the hypothesis that older children rely also, but to a lesser extent, on visual working memory. Experiment 1 confirmed previous evidence that 11-year-olds' memory is disrupted by phonemic similarity of object names, but is unaffected by visual similarity of the objects themselves. However, when articulatory suppression was used to prevent phonological coding, levels of recall were sensitive to visual rather than phonemic similarity. Experiment 2 compared the effects of interpolating an auditory-verbal or a visual postlist task on memory for drawings viewed either with or without suppression. The visual task had a clear disruptive effect only in the suppression condition, where it interfered selectively with recall of the most recent item. Experiment 3 compared the effects of interpolating an auditory-verbal or a mixed-modality (visual-auditory) postlist task when subjects were not required to suppress. There was greater interference from the mixed-modality task, and this effect was confined to the last item presented. These experiments are taken as confirming the presence of a small but reliable contribution from visual memory in 11-year-old children's recall. As in younger children, visual working memory in 11-year-olds is sensitive to visual similarity and is responsible for a final-item visual recency effect. The results also show that older children's use of visual working memory is usually masked by the more pervasive phonological component of recall. Some implications for the structure of working memory and its development are discussed.     

Word length and age influences on forward and backward immediate serial recall

The present research is aimed at understanding the processes involved in short-term memory and how they interact with age. Specifically, word length effects were examined under forward serial recall, backward serial recall, and item recognition tasks, with performance being interpreted within an item-order theoretical framework. The interaction of age, word length, and direction of recall was examined in two experiments, the first of which confirmed that the word length was present with forward recall and absent with backward recall. In addition, age effects were stronger in backward recall than in forward recall. In the second experiment, an item-order trade-off methodology was utilized with backward recall. When order memory was required, there was no word length effect and strong age effects. When memory was tested via an item recognition test, there was a reverse word length effect and no age effect. While word length effects can be interpreted within the item-order framework, age effects cannot.     

Implicit sequence learning in deaf children with cochlear implants

Deaf children with cochlear implants (CIs) represent an intriguing opportunity to study neurocognitive plasticity and reorganization when sound is introduced following a period of auditory deprivation early in development. Although it is common to consider deafness as affecting hearing alone, it may be the case that auditory deprivation leads to more global changes in neurocognitive function. In this paper, we investigate implicit sequence learning abilities in deaf children with CIs using a novel task that measured learning through improvement to immediate serial recall for statistically consistent visual sequences. The results demonstrated two key findings. First, the deaf children with CIs showed disturbances in their visual sequence learning abilities relative to the typically developing normal-hearing children. Second, sequence learning was significantly correlated with a standardized measure of language outcome in the CI children. These findings suggest that a period of auditory deprivation has secondary effects related to general sequencing deficits, and that disturbances in sequence learning may at least partially explain why some deaf children still struggle with language following cochlear implantation.     

Free recall by deaf and hearing children: semantic clustering and recall in trained and untrained groups.

Free recall tasks with semantically categorizable stimuli were given to 60 deaf and 60 hearing children, divided equally among Grades 3, 5, and 7 (ages 9, 11, and 13 years, respectively). Half the children were trained to use semantic categorization as a memory aid after the first study-test trial. All subjects were told category labels and sizes on the third recall trial. As hypothesized, older children showed more spontaneous semantic clustering and higher recall scores than younger children. Training increased clustering in all groups, while the provision of category information at retrieval increased clustering regardless of training condition. Contrary to expectations, deaf children used semantic clustering as much as hearing children. Deaf children's recall scores, however, were significantly lower than hearing children's. The specific contrasts observed between deaf and hearing children's performance suggest that deaf children's recall deficiencies probably reflect either inadequate knowledge of category membership or inflexibility in reclassifying individual items, rather than a general inability to recognize and use the categorical nature of a list as a mnemonic aid.     

The recall of digits by normal, deaf and autistic children.

Normal, autistic and deaf children were tested for their immediate memory of visually presented digits. The digits were exposed either with or without a left to right spatial display arrangement, and had to be recalled forewards as well as backwards. Normal and deaf children tended to be sensitive to both display conditions and recall requirements whereas autistic children were mainly affected by direction of recall. Serial position effects in the normal and deaf groups were more dependent on order of retrieval than on input order.     

Visual working memory in young children

Five experiments investigated immediate memory for drawings of familiar objects in children of different ages. The aims were to demonstrate younger children’s greater dependence on visual working memory and to explore the nature of this memory system. Experiment 1 showed that visual similarity of drawings impaired recall in young (5-year-old) children but not in older (10-year-old) children. Experiment 2 showed that younger and older children were affected in contrasting ways when the temporal order of recall was manipulated. Experiment 3 explored a recency effect found in backward recall and investigated its sensitivity to the presentation modality of materials used to produce retroactive interference (RI). For younger children, recency was reduced by visual but not by auditory-verbal RI; for older children, recency was more sensitive to auditoryverbal RI. Experiment 4 confirmed the effect of visual RI on visual recency in young children and showed that the same RI had little effect on their recall of spoken words. These results confirm younger children’s dependence on visual working memory. A final experiment showed that the effects of visual similarity and visual RI are additive, suggesting that they reflect different modes of accessing stored visuospatial information. Implications of these findings for developmental issues and for the nature of visual working memory are discussed.     

Phonemic effects in the silent reading of hearing and deaf children

Twenty-four deaf and hearing children silently read a printed passage while crossing out all detected cases of a pre-specified target letter. Target letters appeared in phonemically modal form, a category loosely analogous to “pronounced” letters (e.g., the g in badge), and in phonemically nonmodal form, a class which included “silent” letters and those pronounced in somewhat atypical fashion (e.g., the g in rough). Hearing children detected significantly more modal than nonmodal forms, an expected pronunciation effect for individuals in whom speech and reading ordinarily are in close functional relationship. The deaf detected exactly as many modal as nonmodal letter forms, provoking the interpretation that deaf children, as a group, do not effectively mediate print with speech. The deaf also were relatively unaffected by grammatical class, while hearing subjects were considerably more likely to detect a target letter if it occured in a content word than a functor term. Questions pertaining to reading instruction in the deaf are discussed.     

Deafness and immediate memory for pictures: dissociations between "inner speech" and the "inner ear"?

Born-deaf, orally trained youngsters were examined on two tasks of immediate memory for pictures of objects. The aim was to investigate the extent of speech coding for pictures in immediate memory in a developmental context. The deaf, unlike young hearing children, did not use picture-name rhyme spontaneously as a cue to recall in a paired association task. Nevertheless, they were just as sensitive as reading age-matched hearing controls to spoken word length in recalling pictures by name. This might mean that the deaf use articulatory rehearsal in some immediate memory tasks, but this leads to a paradoxical conclusion. What could "inner speech" in the deaf be for, if it fails to affect their "inner ear" by inducing rhyme sensitivity in the paired associate task? This paradox is discussed in relation to distinctions between covert and overt use of memory cues in the paired recall task and to possible sources of the word length effect in young hearing (8-9 years old) and deaf subjects.     

Allocation of attention, reading skills, and deafness.

Brannan and Williams (1987) found that poor readers cannot successfully utilize parafoveal cues to identify letter targets. Whether a similar deficit in the use of cue information occurs in deaf poor readers and whether it is only specific to processes that capture attention automatically were investigated in congenitally deaf young adults classified as poor or good readers and hearing controls classified as good readers. Subjects were presented with central or parafoveal cues that varied in cue validity probability, followed by letter targets presented to the left or right of fixation. The reaction time data analyses showed significant main effects for cue type and cue location and significant interactions among cue type, cue location, cue validity probability, and visual field. No significant main effect or interactions involving groups were found. These results raise the possibility that reading difficulties associated with deafness do no involve a deficit in the visual attentional system of deaf people. They also confirm that parafoveal cues are more effective than central cues in capturing attention.     

Speech timing and working memory in profoundly deaf children after cochlear implantation

Thirty-seven profoundly deaf children between 8- and 9-years-old with cochlear implants and a comparison group of normal-hearing children were studied to measure speaking rates, digit spans, and speech timing during digit span recall. The deaf children displayed longer sentence durations and pauses during recall and shorter digit spans compared to the normal-hearing children. Articulation rates, measured from sentence durations, were strongly correlated with immediate memory span in both normal-hearing and deaf children, indicating that both slower subvocal rehearsal and scanning processes may be factors that contribute to the deaf children's shorter digit spans. These findings demonstrate that subvocal verbal rehearsal speed and memory scanning processes are not only dependent on chronological age as suggested in earlier research by. Instead, in this clinical population the absence of early auditory experience and phonological processing activities before implantation appears to produce measurable effects on the working memory processes that rely on verbal rehearsal and serial scanning of phonological information in short-term memory.     

Foveal-to-peripheral priming in letter identification reflects response bias, not enhanced visibility

Several studies have suggested that it might be easier to identify a letter when its replication is simultaneously presented in the visual display. We have measured identification accuracy for a memorized target letter that was shown in the peripheral field in two conditions in which a letter either identical or different in shape was flashed simultaneously at fixation. The results of three forced-choice experiments showed that, contrary to Geiger and Lettvin's (1986) previous findings, an identity prime did not improve the visibility of a temporally backward masked target letter. However, the foveal prime letter could apparently bias the subject's decision so that he/she was much more ready to report the more visible prime letter as the peripheral target.     

Are forward and backward recall the same? A dual-task study of digit recall

There is some debate surrounding the cognitive resources underlying backward digit recall. Some researchers consider it to differ from forward digit recall due to the involvement of executive control, while others suggest that backward recall involves visuospatial resources. Five experiments therefore investigated the role of executive-attentional and visuospatial resources in both forward and backward digit recall. In the first, participants completed visuospatial 0-back and 2-back tasks during the encoding of information to be remembered. The concurrent tasks did not differentially disrupt performance on backward digit recall, relative to forward digit recall. Experiment 2 shifted concurrent load to the recall phase instead and, in this case, revealed a larger effect of both tasks on backward recall, relative to forwards recall, suggesting that backward recall may draw on additional resources during the recall phase and that these resources are visuospatial in nature. Experiments 3 and 4 then further investigated the role of visual processes in forward and backward recall using dynamic visual noise (DVN). In Experiment 3, DVN was presented during encoding of information to be remembered and had no effect upon performance. However, in Experiment 4, it was presented during the recall phase, and the results provided evidence of a role for visual imagery in backward digit recall. These results were replicated in Experiment 5, in which the same list length was used for forward and backward recall tasks. The findings are discussed in terms of both theoretical and practical implications.