Further analysis of encoding in patients with Huntington's disease

Arguments favoring the view that derangement of normal encoding processes contributes to the memory defects of patients with Huntington's disease (HD) are supported by the finding that HD patients do not learn highly imageable words more rapidly than they learn words that are difficult to image. But other data indicating that HD patients can use verbal mediators as mnemonic aids for picture recognition question the existence of important and general encoding deficits in HD. In the first of two experiments the influence of imagery on the acquisition and recall of 14-word lists was studied using a free-recall paradigm. Both HD patients and controls learned highly imageable words more quickly and retained them better than low imagery words over a 30-min delay. The impact of imagery on learning was apparent by the first trial. In the second experiment, a modified Brown-Peterson distractor paradigm was used to assess release from proactive interference (PI). It was found that both HD patients and controls exhibited comparable release from PI following a shift in taxonomic categories. The results of both experiments question the importance of encoding deficits in the memorial dysfunctions associated with HD.     

Ressourcenaktivierung bei Patienten

Background

Starting from Klaus Grawe’s draft of a general psychotherapy, the patient’s resources and resource-activating interventions have received increasing attention in empirical research.

Objective

The effectiveness of standardized writing instructions for the activation of patients’ resources before participating in internet chat aftercare groups for psychosomatic patients was examined.

Method

In a randomized controlled trial writing instruction for the activation of patients’ resources was given in 52 out of 102 internet chat aftercare sessions. The effects of this minimal intervention on the patients’ activity and the number of positive emotion words expressed during the chat session were examined. Additionally, the effects on patients’ self-esteem, attachment, orientation, control and well-being after the group sessions were assessed.

Results

Patients reported higher levels of self-esteem, orientation, control and well-being after chat sessions with a resource-activating intervention. No differences between intervention and control groups were detected on the text-based variables activity and number of positive emotion words.

Conclusions

Standardized minimal interventions for the activation of patients’ resources seem to be promising for enhancing the effectiveness of therapeutic Internet chat groups.     

Encoding processes and sex-role preferences

Seven- and 10-year-old children were tested on memory and sex-role preference tasks. The memory task was the Wickens release from proactive inhibition paradigm in which short-term recall of words is tested on successive trials. On Trials 1–4, words were selected from one of two categories, either words with masculine or feminine connotations. On Trial 5, words were drawn from the second category. Sex-role preference was assessed by asking the child to select his favorite pictures from an array that included masculine and feminine items. Recall by boys at both ages increased following a shift between words with masculine or feminine connotations, suggesting that this dimension of a word's meaning was encoded in memory. Recall by girls who selected a feminine item as their favorite on the sex-role preference task increased following a category shift; recall by girls who chose a masculine item did not increase. These results are discussed in relation to previous research on the attributes of encoding in children's memory.     

Differential encoding as a function of semantic polarity and form of visual stimulus presentation

The present study investigated the saliency of form of visual stimulus presentation (printed word or picture) and of the semantic evaluative dimension (positive or negative) as encoding attributes for fifth-grade children. Three short-term memory trials within one visual form of presentation or one pole of the evaluative dimension were followed by a fourth short-term memory trial on which the stimulus material was shifted on one or both attributes (experimentals) or held constant (controls). The recall of the experimental groups consistently exceeded that of the control groups on the shift trial, providing evidence for a release from proaetive inhibition and implying the saliency of both the form of visual stimulus presentation and the evaluative polarity of the stimulus concepts as encoding dimensions.     

Encoding dimensions of subject-performed tasks

Summary In an experiment modelled upon the classical paradigm on release from proactive interference (PI), subjects were required to remember series of actions they had performed (e.g., roll the ball, fold the paper). The objects involved in these subject-performed tasks (SPTs) served as a basis for build-up and release of PI. The objects used in the first few trials of the experiment belonged to the same class (e.g., parts of the body), causing a build up of PI. A shift to a different class of objects (e.g., kitchen utensils) along four different dimensions (taxonomic category, weight, color, and size) was introduced to cause a release of PI. On the basis of PI-release experiments with words it was expected that shifts in taxonomic category would result in a greater release than shifts within any of the physical dimensions. However, the results revealed that the amount of PI release was, in general, larger than expected, and essentially the same for all four dimensions investigated. The results are discussed in terms of the nature of the memory representation of SPTs, and with regard to possible processing differences between SPTs and verbal information. In addition, methodological suggestions for furthering the understanding of the encoding and storage of action events are advanced.     

The role of stimulus material in determining release from proactive inhibition

The release from proactive inhibition (PI) paradigm has been widely used as a technique for exploring the encoding dimensions of short-term memory for verbal items. PI release data have been used not only to infer particular memory codes but also to index their relative salience. In the present study, the effects of manipulating the colour (red or black) in which the stimulus material is printed were investigated in two separate experiments. No release effect was obtained in the first, where common two-syllable words were presented. In the second, where consonant trigrams were presented, a large effect was found. Since the same colour feature was manipulated in each experiment, it is argued that this pattern of results has serious implications for the use of PI release data as a technique for mapping the encoding dimensions of short-term memory.     

记忆编码与特异性效应之间关系的ERP研究

通过事件相关电位（ERPs）探讨了在“学习–再认”模式条件下的记忆编码与特异性效应之间的关系。选择首要特异性特征为深、浅加工,次要特异性特征为高、低词频。研究结果表明,（1）行为数据支持了低频词的再认比高频词更精确;深加工的再认比浅加工更精确,并且深加工存在着显著的字频效应,浅加工没有显著的字频效应。（2）低频词比高频词有更大的ERP晚正成分（LPC）;在低频词条件下,存在着显著的相继记忆效应,随后再认正确的ERPs比随后再认不正确的ERPs更正。因此,加工方式和词频间接地影响着记忆编码的形成。     

How do students improve their value-based learning with task experience?

When learning items that vary in reward, students improve their scores (i.e., earned reward) with task experience. In four experiments, we examined whether such improvements arise from better selective encoding of items that would earn more (vs. less) reward. Participants studied and recalled words across multiple study-test trials. On each trial, 12 words were slated with different values (typically from 1 to 12), and participants earned the point value assigned to a given word if it was correctly recalled. In all experiments, participants earned more points across the first two trials. In Experiment 1, participants either self-paced their study or had experimenter-paced study and in Experiment 2, some participants were penalised for each second spent during study. Improvements in points earned were related to increases in overall recall but not to selective encoding. In Experiment 3, some participants were given value-emphasised instructions, yet they did not demonstrate selective encoding. In Experiment 4, we used a larger range of point values, but selective encoding still did not account for the improvement in point scores across lists. These results suggest that metacognitively-driven selective encoding is not necessary to observe improvements in value-based learning.     

Some analyses of the verbal encoding deficit of alcoholic Korsakoff patients

Two experiments were designed to assess Korsakoff patients' ability to encode verbal information on the basis of its physical, nominal and semantic properties. The first investigation employed Wickens' release from proactive interference (PI) technique; a procedure that allows an assessment of a subject's ability to encode verbal information on the basis of its semantic properties. It was discovered that on tasks involving only a rudimentary verbal analysis, such as the ability to discriminate letters from numbers, the Korsakoff patients demonstrated a normal release from PI. However, on tasks that required a more sophisticated level of semantic encoding, such as those based on taxonomic class inclusion, the patients failed to show release from PI. The second investigation employed Posner's reaction time technique which assesses a subject's ability to encode the physical and nominal properties of simple verbal materials (letters). The results of this study showed that Korsakoff patients are impaired on even these rudimentary encoding tasks, which led to the proposal that Korsakoff patients' semantic encoding deficit might stem from an initial impairment in the speed at which physical and nominal properties of verbal information are analyzed.     

Identity and semantic negative priming in rapid serial visual presentation streams

In selective attention tasks, the efficiency of processing concurrently presented target and distractor stimuli in a given display is often influenced by the relationship these stimuli have with those in the previous display. When a to-be-attended target on a current trial (the probe trial) matches the ignored, non-target distractor on a previous trial (the prime trial), a response to the target is typically delayed compared with when the two stimuli are not associated. This negative priming (NP) phenomenon has been observed in numerous studies with traditional NP tasks presenting the target and distractor simultaneously in both the prime and probe trial couplets. Here, however, in four experiments using a mixture of stimulus types (letters, digits, English number words, and logographic Chinese number words), target and distractor stimuli were temporally separated in two rapid serial visual presentation (RSVP) streams instead of concurrently presented. The findings provide a conceptual replication and substantial extension of a recent study by Wong (Plos One, 7, e37023, 2012), and suggest that active suppression of irrelevant distracting information is a more ubiquitous form of cognitive control than previously thought.     

Girls Not Boys Show Gender-Connotation Encoding from Print

The present study examines gender differences in children's encoding of gender-connotation from words. The release from proactive interference method was used to measure gender-connotation encoding. Forty-eight third-grade children attending a public elementary school serving a predominantly White middle-socioeconomic-status community participated and were presented with stimulus words in print. The design of the study can be characterized as a two (gender) by two (condition: control vs. experimental) by four (trials) factorial. Results revealed reliable proactive interference buildup and release for gender-connotation for girls, but not for boys. This new finding, taken together with extant research, demonstrates that while both boys and girls have the ability to encode gender-connotation from aurally presented words, the spontaneous activation of gender-connotation attributes with print is not guaranteed for boys.     

Grapheme–color synesthesia can enhance immediate memory without disrupting the encoding of relational cues

Previous evidence has suggested that grapheme–color synesthesia can enhance memory for words, but little is known about how these photisms cue retrieval. Often, the encoding of specific features of individual words can disrupt the encoding of ordered relations between words, resulting in an overall decrease in recall accuracy. Here we show that the photisms arising from grapheme–color synesthesia do not function like these item-specific cues. The influences of high and low word frequency on the encoding of ordered relations and the accuracy of immediate free recall were compared across a group of 10 synesthetes and 48 nonsynesthetes. The main findings of Experiment 1 showed that the experience of synesthesia had no adverse effect on the encoding of ordered relations (as measured by input–output correspondence); furthermore, it enhanced recall accuracy in a strictly additive fashion across the two word frequency conditions. Experiment 2 corroborated these findings by showing that the synesthetes only outperformed the nonsynesthetes when the materials involved words and letters, not when they involved digits and spatial locations. Altogether, the present findings suggest that synesthesia can boost immediate memory performance without disrupting the encoding of ordered relations.     

Cross‐Situational Learning of Phonologically Overlapping Words Across Degrees of Ambiguity

Cross‐situational word learning (XSWL) tasks present multiple words and candidate referents within a learning trial such that word–referent pairings can be inferred only across trials. Adults encode fine phonological detail when two words and candidate referents are presented in each learning trial (2 × 2 scenario; Escudero, Mulak, & Vlach, 2016a ). To test the relationship between XSWL task difficulty and phonological encoding, we examined XSWL of words differing by one vowel or consonant across degrees of within‐learning trial ambiguity (1 × 1 to 4 × 4). Word identification was assessed alongside three distractors. Adults finely encoded words via XSWL: Learning occurred in all conditions, though accuracy decreased across the 1 × 1 to 3 × 3 conditions. Accuracy was highest for the 1 × 1 condition, suggesting fast‐mapping is a stronger learning strategy here. Accuracy was higher for consonant than vowel set targets, and having more distractors from the same set mitigated identification of vowel set targets only, suggesting possible stronger encoding of consonants than vowels.     

Words translated in sentence contexts produce repetition priming in visual word comprehension and spoken word production

Previous research with words read in context at encoding showed little if any long-term repetition priming. In Experiment 1, 96 Spanish–English bilinguals translated words in isolation or in sentence contexts at encoding. At test, they translated words or named pictures corresponding to words produced at encoding and control words not previously presented. Repetition priming was reliable in all conditions, but priming effects were generally smaller for contextualized than for isolated words. Repetition priming in picture naming indicated priming from production in context. A componential analysis indicated priming from comprehension in context, but only in the less fluent language. Experiment 2 was a replication of Experiment 1 with auditory presentation of the words and sentences to be translated. Repetition priming was reliable in all conditions, but priming effects were again smaller for contextualized than for isolated words. Priming in picture naming indicated priming from production in context, but the componential analysis indicated no detectable priming for auditory comprehension. The results of the two experiments taken together suggest that repetition priming reflects the long-term learning that occurs with comprehension and production exposures to words in the context of natural language.     

Behavioral and neural analyses of connotative meaning: Word classes and rating scales

Behavioral (semantic differential) and neural (Evoked Potentials, EPs) responses were related to connotative meaning. The approach was based on Osgood's semantic analyses and dimensions of Evaluation (E), Potency (P), and Activity (A). The experimental variables were (1) the semantic class of the stimulus word (E+, E-, P+, P-, A+, A-) and (2) the dimension of the semantic scale (E, P, A) which the subject used to rate the stimulus words. These variables were experimentally combined such that on each trial the subject used a designated semantic scale to judge a specified stimulus word while brain activity was recorded. Using multivariate analyses, the effects on the EPs of stimulus word class, scale dimension, and their interaction were analyzed. The EP effects of stimulus word class were similar whether the subjects were merely saying the words or rating the words on a variety of semantic scales. Different EPs were found for six word classes, three semantic scale dimensions, and the 18 groups formed by their combination. The success rates in EP identification of (1) word class and (2) scale dimension did not depend on whether these two kinds of semantic variables involved the same or different semantic dimensions. The two kinds of semantic effects in EPs were largely independent. The behavioral data supported Osgood's results and showed that our subjects were appropriately processing the semantic information. The common analyses of data from all subjects suggest the universality of the connotative EP effects across individuals. This parallels, at the neural level, the universality of the connotative dimensions found at the behavioral level by semantic differential ratings. The EP effects imply that the neural representation of meaning is similar in different individuals.     

FUNCTIONAL MAGNETIC RESONANCE IMAGING OF SEMANTIC MEMORY PROCESSES IN THE FRONTAL LOBES

Abstract— Frontal-lobe activation during semantic memory performance was examined using functional magnetic resonance imaging (fMRI), a noninvasive technique for localizing neural activity associated with cognitive function. Left inferior prefrontal cortex was more activated for semantic than for perceptual encoding of words, and for initial than for repeated semantic encoding of words. Decreased activation for semantic encoding of repeated words reflects repetition priming, that is, implicit retrieval of memory gained in the initial semantic encoding of a word. The left inferior prefrontal region may sub-serve semantic working memory processes that participate in semantic encoding and that have decreased demands when such encoding can be facilitated by recent semantic experience. These results demonstrate that fMRI can visualize changes in an individual's brain function associated with the encoding and retrieval of new memories.     

Reminders can enhance or impair episodic memory updating: a memory-for-change perspective

ABSTRACT

The Memory-for-Change framework proposes that retrieving episodic memories can facilitate new learning when changes between existing memories and new information are integrated during encoding and later recollected. Four experiments examined whether reminders could improve memory updating and enhance new learning. Participants studied two study lists of word pairs and were given a cued recall test on responses from both lists. Reminders of List 1 words pairs (A-B) appeared immediately before List 2 words pairs that included repeated cues and changed responses (A-D). Across experiments, we varied the types of reminders to determine whether differences in their effectiveness as retrieval cues would influence memory for the list membership of responses. We found that presenting intact reminders (cue-response) enhanced the memory benefits associated with recollection-based retrieval of changes relative to when no reminders appeared and when partial reminders (cue-only) appeared with and without feedback. Importantly, cue-response reminders benefitted memory when they were recognised in List 2 and when changes were later recollected. This suggests that integrative encoding can be facilitated when substantial environmental support is available to cue retrieval of existing memories. These findings have practical implications for understanding which reminders best aid the correction of memories for inaccurate information.     

Encoding specificity and unidirectional associates in cued recall

The first of two experiments confirmed the earlier findings of Humphreys and Galbraith (1975), that under silent-study encoding instructions, words assessed as strong elicitors of target words are effective extralist retrieval cues, whereas words assessed as weak elicitors are not. In the second experiment, predictions from the encoding specificity principle were confirmed with respect to the effectiveness of forward and backward retrieval cues in recall. Contrary to the conclusions of Humphreys and Galbraith, forward and backward unidirectional associates were equally effective as retrieval cues, provided subjects engaged in associative encoding (generated associations to the target words) at storage.     

注意促进效应的ERP研究

近期发现,采用目标探测任务作为二级任务时,目标探测条件不仅不会削弱,甚至会提高记忆成绩,产生注意促进效应（ABE）。为进一步探究目标探测的作用机制,研究采用事件相关电位（ERP）技术,对比目标与分心条件在编码和提取过程中所诱发的ERP差异。结果表明,两类条件在再认过程中所诱发的ERP差异不仅表现在早期与知觉加工相关的ERP成份上,并且一直持续到了后期与细节提取相关的ERP成分上。由此推测,ABE不仅体现在编码早期的知觉加工阶段,更会延续到后期的复述与精加工。