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Purpose: Dietary flavonoids, including anthocyanins, may positively influence cognition and may be beneficial for the prevention and treatment of dementia. We aimed to assess whether daily consumption of anthocyanin-rich cherry juice changed cognitive function in older adults with dementia. Blood pressure and anti-inflammatory effects were examined as secondary outcomes., Methods: A 12-week randomised controlled trial assessed cognitive outcomes in older adults (+70 year) with mild-to-moderate dementia (n = 49) after consumption of 200 ml/day of either a cherry juice or a control juice with negligible anthocyanin content. Blood pressure and inflammatory markers (CRP and IL-6) were measured at 6 and 12 weeks. ANCOVA controlling for baseline and RMANOVA assessed change in cognition and blood pressure., Results: Improvements in verbal fluency (p = 0.014), short-term memory (p = 0.014) and long-term memory (p ≤ 0.001) were found in the cherry juice group. A significant reduction in systolic (p = 0.038) blood pressure and a trend for diastolic (p = 0.160) blood pressure reduction was evident in the intervention group. Markers of inflammation (CRP and IL-6) were not altered., Conclusion: Inclusion of an anthocyanin-rich beverage may be a practical and feasible way to improve total anthocyanin consumption in older adults with mild-to-moderate dementia, with potential to improve specific cognitive outcomes.

Estrogen is known to modulate certain cognitive functions, most notably improving working memory and verbal memory. Soy foods contain isoflavones, phytoestrogens structurally similar to estrogen that weakly bind to estrogen receptors. We investigated the effects of natural variations in estrogen levels and short-term dietary supplementation with soy isoflavones on cognitive function in 28 young women. Performance was examined across a range of cognitive tasks on three occasions during separate menstrual cycles: during a menses phase (low estrogen), during a luteal phase (highest estrogen), and once during a menses phase after a 3-day phytoestrogen-rich dietary intervention. Soy supplementation during menses led to an improvement in working memory and verbal memory. The menstrual cycle effects were mixed, with high estrogen improving performance on a verbal memory task but not on working memory. Our results suggest that soy phytoestrogens may improve working memory through estrogen-independent mechanisms.

A study is reported on the effects of Brahmi (Bacopa monniera) on human memory. Seventy-six adults aged between 40 and 65 years took part in a double-blind randomized, placebo control study in which various memory functions were tested and levels of anxiety measured. There were three testing sessions: one prior to the trial, one after three months on the trial, and one six weeks after the completion of the trial. The results show a significant effect of the Brahmi on a test for the retention of new information. Follow-up tests showed that the rate of learning was unaffected, suggesting that Brahmi decreases the rate of forgetting of newly acquired information. Tasks assessing attention, verbal and visual short-term memory and the retrieval of pre-experimental knowledge were unaffected. Questionnaire measures of everyday memory function and anxiety levels were also unaffected.

Complex networks describe how entities in systems interact; the structure of such networks is argued to influence processing. One measure of network structure, clustering coefficient, C, measures the extent to which neighbors of a node are also neighbors of each other. Previous psycholinguistic experiments found that the C of phonological word-forms influenced retrieval from the mental lexicon (that portion of long-term memory dedicated to language) during the on-line recognition and production of spoken words. In the present study we examined how network structure influences other retrieval processes in long- and short-term memory. In a false-memory task--examining long-term memory--participants falsely recognized more words with low- than high-"C". In a recognition memory task--examining veridical memories in long-term memory--participants correctly recognized more words with low- than high-"C". However, participants in a serial recall task--examining reintegration in short-term memory--recalled lists comprised of high-"C" words more accurately than lists comprised of low-C words. These results demonstrate that network structure influences cognitive processes associated with several forms of memory including lexical, long-term, and short-term. (Contains 4 tables and 4 figures.)

The aim of the present research was to determine whether the effect that phonological similarity has on immediate serial recall is influenced by the consistency and position of phonemes within words. In comparison to phonologically dissimilar lists, when the stimulus lists rhyme there is a facilitative effect on the recall of item information and a detrimental effect on order memory (Experiment 1). When stimuli share the initial consonant and vowel (Experiment 2) or the same initial and final consonant (Experiment 3), there is no beneficial effect of similarity for item information, coupled with a detrimental effect on order memory. Contrary to the predictions made by non-linguistic models of STM, the influence that similarity has on both the recall of item information and memory for the position of items in a list is dependent on which components of the items are shared within a list.

Suggests that phonological short-term memory (STM) tasks are influenced by both lexical and sublexical factors inherent in the selection and construction of the stimuli to be recalled. Examined whether long-term memory influences STM at a sublexical level by investigating whether the frequency with which one-syllable nonwords occur in polysyllabic words influences recall accuracy on two phonological STM tasks, nonword repetition and serial recall. (Author/VWL)

This paper explores the impact of phonological overlap amongst items on short term memory recall performance by manipulating the type, number and syllabic position of shared phonemes between words in a serial recall task. Roodenrys et al [Roodenrys, S., Miller., L. M., & Josifoski, N. (2022b). Phonemic interference in short-term memory contributes to forgetting but it is not due to overwriting. Journal of Memory and Language, 122, 104301. https://doi.org/10.1016/j.jml.2021.104301] demonstrated that when the phonemes of a target word also occur in words earlier in the list, recall of the target word is impaired. Two experiments are reported that further examine the nature of this interference effect. Experiment 1 varied the type and number of phonemes shared with the single syllable target word by other list words and found a single shared vowel impaired target word recall performance as much as two shared consonants. Experiment 2 altered the syllabic position of the overlapping phonemes and found shared syllabic position was necessary to impair recall of the target word. It is argued these results show that not all phonological overlap is equally detrimental and specific psycholinguistic conditions are necessary to produce interference that impairs recall performance. [ABSTRACT FROM AUTHOR]

The phonological similarity effect in short‐term memory (STM) is the finding that serial recall of lists of similar sounding items is poorer than that of dissimilar sounding items. This is traditionally argued to be due to a detrimental effect on memory for the order of the words in the list and not on memory for the words themselves. Models that propose forgetting from STM is due to interference must invoke an additional compensatory process where the shared element of the words acts as a cue to recall, in order to account for the lack of an effect on memory for the words. However, the possibility of a detrimental effect of phonological similarity on item memory when these compensatory processes are not available has not been investigated. Two experiments (n = 60 and n = 57) in which similarity is operationalized in a way that precludes usage of compensatory processes are reported. The results clearly demonstrate that item recall is poorer for similar lists than dissimilar lists when similarity is defined in this way. [ABSTRACT FROM AUTHOR]

The frequency effect in short-term serial recall is influenced by the composition of lists. In pure lists, a robust advantage in the recall of high-frequency (HF) words is observed, yet in alternating mixed lists, HF and low-frequency (LF) words are recalled equally well. It has been argued that the preexisting associations between all list items determine a single, global level of supportive activation that assists item recall. Preexisting associations between items are assumed to be a function of language co-occurrence; HF-HF associations are high, LF-LF associations are low, and mixed associations are intermediate in activation strength. This account, however, is based on results when alternating lists with equal numbers of HF and LF words were used. It is possible that directional association between adjacent list items is responsible for the recall patterns reported. In the present experiment, the recall of three forms of mixed lists-those with equal numbers of HF and LF items and pure lists-was examined to test the extent to which item-to-item associations are present in serial recall. Furthermore, conditional probabilities were used to examine more closely the evidence for a contribution, since correct-in-position scoring may mask recall that is dependent on the recall of prior items. The results suggest that an item-to-item effect is clearly present for early but not late list items, and they implicate an additional factor, perhaps the availability of resources at output, in the recall of late list items. [ABSTRACT FROM AUTHOR]

Word frequency and word concreteness are language attributes that have been shown to independently influence the recall of items in verbal short-term memory (STM). It has been argued that such effects are evidence for the action of long-term memory knowledge on STM traces. However, research to date has not investigated whether these variables interact in serial recall. In two experiments, we examined the behavior of these variables under factorial manipulation and demonstrated that the effect of word frequency is dependent on the level of concreteness of items. Serial recall performance is examined with reference to two explanatory approaches: Walker and Hulme's (1999) dual-redintegration account and language-based models of STM. The data indicate that language-based models are more compatible with the observed effects and challenge the view that frequency and concreteness effects in STM are the products of distinct mechanisms. [ABSTRACT FROM AUTHOR]

The notion that verbal short-term memory tasks, such as serial recall, make use of information in long-term as well as in short-term memory is instantiated in many models of these tasks. Such models incorporate a process in which degraded traces retrieved from a short-term store are reconstructed, or redintegrated (Schweickert, 1993), through the use of information in long-term memory. This article presents a conceptual and mathematical model of this process based on a class of item-response theory models. It is demonstrated that this model provides a better fit to three sets of data than does the multinomial processing tree model of redintegration (Schweickert, 1993) and that a number of conceptual accounts of serial recall can be related to the parameters of the model. [ABSTRACT FROM AUTHOR]

Abstract: It has been proposed that a frontally distributed ERP negativity reflects rehearsal within the phonological loop component of working memory. This study investigated the relationship between phonological rehearsal and frontal negativity, by examining the effects of word length and articulatory suppression (continuously uttering an irrelevant word) on memory for auditorily presented words while ERPs were recorded. P2 amplitude, thought to reflect word identification, was increased for long compared to short words. However, this difference did not remain under conditions of suppression. A centrally maximum early negativity was larger in the short than long word silent conditions and this word length effect was reduced under suppression. The early negativity was interpreted as reflecting the transfer of the information from input to output buffers in the silent conditions that was prevented by the suppression. There was only a word length effect for the late frontally distributed negativity in the suppression conditions, suggesting that this component was not associated with phonological loop rehearsal but rather other working memory processes that operate under high load conditions. [Copyright &y& Elsevier]

The current research examined the predictions that short-term memory models generate for the phonological similarity effect, when similarity was defined in different ways. Three serial recall experiments with consonant–vowel–consonant (CVC) nonwords are reported, where the position of the phonemes that list items shared was manipulated (i.e., shared vowel and final consonant [_VC; Experiment 1], initial consonant and vowel [CV_; Experiment 2], or the two consonants [C_C; Experiment 3]. The results show that the position of common phonemes in nonwords has differential effects on order and item information. The findings are discussed in relation to previous research into the effect of phonemic similarity on nonword recall, and modifications to current short-term memory models are proposed. [ABSTRACT FROM AUTHOR]

An experiment is reported examining the effect of consistent phonemic similarity among list items on memory retention in a task that is independent of overt speech production, the serial recognition task. Lists of consonant‐vowel‐consonant (CVC) words and nonwords were constructed such that although phoneme overlap was manipulated (i.e., shared vowel and final consonant [_VC], initial consonant and vowel [CV_], or the two consonants [C_C]), similarity remained constant. The results show that the influence of sub‐syllabic mechanisms on STM performance is independent of speech production processes, and similarity in the pattern of results suggests that the same mechanisms subserve the recall of words and nonwords in STM. It is argued that the results are more consistent with psycholinguistic models than nonlinguistic models of STM, and implications for current STM models are discussed. [ABSTRACT FROM AUTHOR]

The neighbourhood size effect refers to the finding of better memory for words with more orthographic/ phonological neighbours than otherwise comparable words with fewer neighbours. Although many studies have replicated this result with serial recall, only one has used serial recognition. Greeno et al. (2022) found no neighbourhood size effect when a large stimulus pool was used and a reverse effect--better performance for small neighbourhood words--when a small stimulus pool was used. We reexamined these results but made two methodological changes. First, for the large pool, we randomly generated lists for each subject rather than creating one set of lists that all subjects experienced. Second, for the small pool, we randomly generated a small pool for each subject rather than using one small pool for all subjects. In both cases, we observed a neighbourhood size effect consistent with results from the serial recall literature. Implications for methodology and theoretical accounts of both the neighbourhood size effect and serial recognition are discussed. [ABSTRACT FROM AUTHOR]

n serial recall tasks, presenting items in alternating female and male voices impairs performance relative to the single-voice presentation. This phenomenon, termed the talker-variability effect (TVE), was recently reexamined by Hughes, Marsh, and Jones (2009, 2011), who used the effect as confirmatory evidence for their perceptual-gestural account of serial recall performance. Despite the authors' claim of generalisability, the serial recall paradigm employed did not reflect the standard parameters more generally adopted in verbal short-term memory research. Specifically, the presentation rate of the stimuli was almost 3 times that typically used. We sought to determine if the TVE, as observed by Hughes et al., was generalisable to the standard serial recall task by directly comparing recall performance in talker-variable conditions at fast and slow stimulus presentation rates. Experiment 1 employed a systematic replication of the foundational study undertaken by Hughes et al. (2009). Utilising a novel stimulus set, Experiment 2 provided a subsequent test of the generalisability of the TVE, examining the influence of item properties. Both experiments showed a robust TVE at the atypical fast presentation rate; however, for the slower item presentation, the TVE was unreliable. Furthermore, error analysis suggests that item recall also contributes to the TVE, contrary to the current explanation proposed by Hughes et al. (2009, 2011). The challenge of the present data to the perceptual-gestural account of the TVE is explored. Alternative accounts that focus on the resource cost of categorical speech perception in the context of talker variability are posited. [ABSTRACT FROM AUTHOR]

Research on the role of dietary anthocyanins in preventing cognitive decline in older adults shows promise. This study investigated the association between usual anthocyanin intake and indices of memory and cognition in 40 older adults diagnosed with mild cognitive impairment that were recruited to a randomized clinical trial. It was hypothesized that daily anthocyanin intake would be similar to healthy older adults and that higher anthocyanin intake would be associated with better cognitive performance. Cognitive performance was assessed using a battery of tests including the Rey Auditory Verbal Learning Test (RAVLT). Dietary intake was assessed through 3-day food records and anthocyanin intake was quantified using the PhenolExplorer food composition database. Multivariate linear regression compared differences in cognitive performance between higher (>10 mg/d) and lower consumers (<10 mg/d). Overall, participants had low median intake of anthocyanins (5.3; interquartile range [IQR], 32.1 mg/d), with the lower consumer group eating negligible anthocyanins (median, 0.13; IQR, 1.5 mg/d), and the higher consumer group eating above the national average (median, 35.5; IQR, 71.5 mg/d). On the RAVLT, the higher anthocyanin consumer group recalled a greater number of words after a short delay and a distracter task (B, 2.07; standard error [SE], 0.93; 95% confidence interval [CI], 0.18-3.96; P =.03) and longer delay of 20 minutes (B, 2.68; SE, 1.11; 95% CI, 0.43-4.94; P =.02); and forgot less words after a long delay of 20 minutes (B, –2.63; SE, 0.63; 95% CI, –3.90 to –1.35; P <.001). Further investigation of the protective role of the usual consumption of dietary anthocyanins for memory and cognition in pathological and normal aging appears warranted. Trial registration: This cross-sectional study uses baseline data from a randomized controlled trial registered with the Australian New Zealand Clinical Trials Registry (ACTRN12618001184268). [Display omitted] [ABSTRACT FROM AUTHOR]