Improving the encoding of verbal reports by using MPAS: A computer-aided encoding system

The dramatically increased use of verbal report methodologies in psychological research has created a need for new tools to improve the efficiency and reliability of encoding these data. A computer-aided protocol encoding system called MPAS (Multiple Protocol Analysis System) presents individual protocol segments in a randomised order to one or more coders and then stores computer keyboard-entered codes for later output to an SPSS formatted data file. In the present paper, MPAS is described, and a brief example is provided of how MPAS can be used in a con-trolled laboratory study to rigorously analyze verbal protocol data.     

CAPAS 2.0: A computer tool for coding transcribed and digitally recorded verbal reports

A new computer software tool for coding and analyzing verbal report data is described. Combining and extending the capabilities of earlier verbal report coding software tools, CAPAS 2.0 enables researchers to code two different types of verbal report data: (1) verbal reports already transcribed and stored in text files and (2) verbal reports in their original digitally recorded audio format. For both types of data, individual verbal report segments are presented in random order and coded independently of other segments in accordance with a localized encoding principle. Once all reports are coded, CAPAS 2.0 converts the coded reports to a formatted file suitable for analysis by statistical packages such as SPSS. R. J. Crutcher, crutcher@udayton.edu     

Functional asymmetry of human prefrontal cortex: encoding and retrieval of verbally and nonverbally coded information

There are several views about the organization of memory functions in the human prefrontal cortex. One view assumes a process-specific brain lateralization according to different memory subprocesses, that is, encoding and retrieval. An alternative view emphasizes content-specific lateralization of brain systems involved in memory processes. This study addresses this apparent inconsistency between process- and content-specific lateralization of brain activity by investigating the effects of verbal and nonverbal encoding on prefrontal activations during encoding and retrieval of environmental novel sounds using fMRI. An intentional memory task was applied in which subjects were required either to judge the sounds' loudness (nonverbal encoding task) or to indicate whether or not a sound can be verbally described (verbal encoding task). Retrieval processes were examined in a subsequent yes/no recognition test. In the study phase the right posterior dorsolateral prefrontal cortex (PFC) was activated in both tasks. During verbal encoding additional activation of the left dorsolateral PFC was obtained. Retrieval-related fMRI activity varied as a function of encoding task: For the nonverbal task we detected an activation focus in the right posterior dorsolateral PFC whereas an activation in the left dorsolateral PFC was observed for the verbal task. These findings indicate that the right dorsolateral PFC is engaged in encoding of auditory information irrespective of encoding task. The lateralization of PFC activity during retrieval was shown to depend on the availability of verbal codes, with left hemispheric involvement for verbally and right hemispheric activation for nonverbally coded information.     

Interitem encoding and directed search in free recall

The paper proposes a cognitive structure consistent with principles of encoding and a rule for its utilization in verbal recall. The encoding and utilization rules lead to phenomena similar to known serial position effects. A detailed analysis of overt rehearsal data and other experimental results are presented in support of the claim that encoding and search mechanisms characterized by these rules could be important factors in serial position effects of verbal recall. Similar rules might be helpful in dealing with other tasks which seem to mirror the utilization of a cognitive structure.     

Differentiating between verbal and spatial encoding using eye-movement recordings

Visual information processing is guided by an active mechanism generating saccadic eye movements to salient stimuli. Here we investigate the specific contribution of saccades to memory encoding of verbal and spatial properties in a serial recall task. In the first experiment, participants moved their eyes freely without specific instruction. We demonstrate the existence of qualitative differences in eye-movement strategies during verbal and spatial memory encoding. While verbal memory encoding was characterized by shifting the gaze to the to-be-encoded stimuli, saccadic activity was suppressed during spatial encoding. In the second experiment, participants were required to suppress saccades by fixating centrally during encoding or to make precise saccades onto the memory items. Active suppression of saccades had no effect on memory performance, but tracking the upcoming stimuli decreased memory performance dramatically in both tasks, indicating a resource bottleneck between display-controlled saccadic control and memory encoding. We conclude that optimized encoding strategies for verbal and spatial features are underlying memory performance in serial recall, but such strategies work on an involuntary level only and do not support memory encoding when they are explicitly required by the task.     

Gesturing helps memory encoding in aMCI

Encoding in episodic memory is a step often impaired in patients with amnestic Mild Cognitive Impairment (aMCI). However, procedural memory processes are still relatively preserved. In line with previous research on the enactment effect, we investigated the potential benefit of encoding words combined with imitative gestures on episodic memory. Based on the Grober and Buschke’s free/cued recall procedure, we developed the Symbiosis test in which 13 patients with aMCI and 16 healthy elderly participants learned 32 words belonging to 16 different semantic categories either in a verbal encoding (A) or a bimodal (B; verbal and motor imitation) condition, using a blocked ABBA/BAAB procedure. Overall, memory retrieval was better in healthy participants than in patients with aMCI, and better for cued retrieval in the bimodal encoding (gesture cues) than the verbal encoding (category cues) condition, but there was no interaction effect between group and encoding conditions. These results show that performing concomitant gestures can enhance cued episodic memory retrieval in patients with aMCI and in healthy elderly controls. The Symbiosis test broadens the scope of the enactment effect, from action phrases to isolated words learning in patients with aMCI. Future work should investigate how bimodal encoding provides novel perspectives for memory rehabilitation in patients with aMCI.     

Recognition memory as a function of encoding strategy and stimulus codability.

The primary purpose of this research was to determine how imaginal and verbal encoding strategies intereact with various stimulus characteristics to either enhance or retard recognition; the secondary purpose of these studies was to test the conceptual coding hypothesis of Ellis, 1972. A between-groups multivariate factorial analysis of covariance experiment and a within-subjects multivariate factorial analysis of variance experiment were conducted. In Experiment 1 it was found that low-codability shapes were better recognized under the verbal encoding set rather than the imaginal encoding verbal encoding sets; and high-codability shapes were not better recognized than low-codability shapes. However, in Experiment 2, where instructional set was a within-subjects factor, it was found that low-codability shapes were not better recognized under the verbal encoding set than the imaginal encoding set.     

Effects of enactment by professional actors at encoding and retrieval

This experiment investigated memory benefits similar to those found with subject-performed tasks (SPTs) but under widely differing circumstances. Almost all SPT research has shown that as long as enactment takes place at encoding, mode of recall (enactment vs. verbal recall) is immaterial. Using professional actors, the experimenters had previously shown (Noice & Noice, 1999) that movement that was not semantically congruent with the accompanying material produced enhanced recall at retrieval compared to a non-moving condition, a result that did not appear to be due to the fact that retrieval conditions closely resembled encoding conditions. Experiment 1 of the present study replicated and extended this finding, demonstrating that the effect can be found after a delay of five months with actors of varying age and experience, and that the enhancement is not dependent on physical context. Experiment 2 demonstrated that, even with purely verbal retrieval of material that had been equated for memorability, dialogue originally performed when the participants had been engaged in movement from place to place was better recalled than dialogue originally performed when the participants had remained in one location. Taken together, these results indicate that movement at retrieval is not necessary for the nonliteral enactment effect to occur, but that such movement can aid recall compared to a purely verbal mode of report.     

Decomposing the encoding of action events: A dual conception

Two experiments are reported in which we tested the hypothesis that encoding of verbal features of subject-performed tasks or SPTs (e.g., bounce the ball, lift the spoon) is attention-demanding and effortful, whereas physical features of this memory task (e.g., color, weight) are acquired with little effort, and without deliberate encoding strategies. In Experiment 1, subjects were asked to perform a series of SPTs and were examined on recall of verbal instructions and colors of objects involved under conditions of focused or divided attention. In Experiment 2, performance of a series of SPTs was followed by recall of verbal instructions and recall of weights of objects involved. Results of both experiments indicated that recall of the verbal task component was negatively affected by requirements of dual-task performance, whereas recall of both physical task features was equally good in both encoding conditions. The obtained pattern of outcome is interpreted as supportive of the dual conception hypothesis of the nature of the encoding of action events.     

Mental scanning of sonifications reveals flexible encoding of nonspeech sounds and a universal per-item scanning cost

A mental scanning paradigm was used to examine the representation of nonspeech sounds in working memory. Participants encoded sonifications – nonspeech auditory representations of quantitative data – as either verbal lists, visuospatial images, or auditory images. The number of tones and overall frequency changes in the sonifications were also manipulated to allow for different hypothesized patterns of reaction times across encoding strategies. Mental scanning times revealed different patterns of reaction times across encoding strategies, despite the fact that all internal representations were constructed from the same nonspeech sound stimuli. Scanning times for the verbal encoding strategy increased linearly as the number of items in the verbal representation increased. Scanning times for the visuospatial encoding strategy were generally slower and increased as the metric distance (derived metaphorically from frequency change) in the mental image increased. Scanning times for the auditory imagery strategy were faster and closest to the veridical durations of the original stimuli. Interestingly, the number of items traversed in scanning a representation significantly affected scanning times across all encoding strategies. Results suggested that nonspeech sounds can be flexibly represented, and that a universal per-item scanning cost persisted across encoding strategies. Implications for cognitive theory, the mental scanning paradigm, and practical applications are discussed.     

New evidence on the nature of the encoding of action events

Differences in recall patterns between subject-performed tasks (SPTs) and verbal materials have been interpreted in terms of SPTs being nonstrategic or automatically encoded. In a series of three experiments, we tested this notion by comparing free recall of SPTs and sentences in conditions of'(1) nondivided versus divided attention for organizable items, (2) organizable versus nonorganizable items, and (3) nondivided versus divided attention for nonorganizable items. It was found that recall of both SPTs and sentences decreased in conditions of divided attention. A decrease in recall was also observed for both types of material when nonorganizable as compared to organizable materials were used. In addition, the degree of clustering was higher for SPTs than for sentences. These data suggest that there is a strategic component involved in the encoding of SPTs. We propose that the action elements of SPTs (e.g., motor features, shape, texture) are automatically encoded, whereas the verbal component is strategically encoded. It is emphasized that organization is an encoding strategy critical to SPT recall.     

Lateralization of temporal lobe dysfunction and verbal encoding

The contribution of encoding deficits to verbal-learning difficulties known to be associated with temporal lobe dysfunction was investigated. Auditory and visual false-recognition tasks, which assess verbal encoding strategies, were given to patients with left-temporal-lobe (LTL) and right-temporal-lobe (RTL) surgical excisions and to a group of normal controls (NC). On both auditory and visual tasks, LTL patients made significantly more false-recognition errors than the other subjects on related, but not unrelated, words in the test list. The findings indicate that LTL patients are able to initially encode verbal material and that a breakdown in information processing occurs at a later stage. On the auditory tasks, the performance of RTL patients did not differ from that of NC subjects. However, on the visual tasks, RTL patients, as compared to both LTL and NC subjects, made fewer false-recognition errors. The performance of RTL patients, in contrast to LTL patients, could be interpreted as a reduced encoding of the visual attribute of verbal material. Another possible explanation considered was difficulty in familiarity discrimination.     

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.     

The encoding of ignored information

An experiment was conducted to study the dimensions of encoding of verbal material in short-term memory as a function of other demands placed on Ss attention. Eighty Ss shadowed one of two simultaneous lists, under instructions to remember the shadowed or the nonshadowed list, A single recognition probe followed each shadowing trial. Ss judged whether the probed item was (1) identical to, (2) a rhyme of, or (3) a synonym of one of the to be remembered items. Results indicated that acoustic information was encoded from all inputs, regardless of the focus of attention. Evidence for semantic encoding, however, was limited to those conditions in which retention of shadowed material was required. The data were interpreted as contradicting “late selection” theories of attention, which propose that all inputs are analyzed for meaning prior to the focusing of attention.     

Pictorial and verbal encoding in a short-term memory task

The present research attempted to manipulate the encoding modality, pictorial or verbal, of schematic faces with well-learned names by manipulating S’s expectations of the way the material was to be used. On every trial, a single name or face was presented, followed by another one; the S was asked to respond “same” if the stimuli had the same name, and “different” otherwise. The majority of second stimuli of any session was either names or faces. It was hypothesized that if S had encoded the first stimulus in the modality of the second, his judgment would be faster than if he had not appropriately encoded the first stimulus. Significantly slower reaction times were obtained to stimulus pairs where the second stimulus modality was infrequent. Further evidence that encoding of the first stimulus was in the frequent second stimulus modality comes from the finding that “different” responses were shorter when the stimuli differed on more than one attribute in the encoding (second stimulus) modality, regardless of the modality of the stimuli. Thus, evidence is presented that not only can verbal material be pictorially encoded (and vice versa), but that whether either verbal or pictorial material is verbally or pictorially encoded depends on S’s anticipation of what he is to do with the material.     

Automatic semantic encoding in verbal short-term memory: Evidence from the concreteness effect

The concreteness effect in verbal short-term memory (STM) tasks is assumed to be a consequence of semantic encoding in STM, with immediate recall of concrete words benefiting from richer semantic representations. We used the concreteness effect to test the hypothesis that semantic encoding in standard verbal STM tasks is a consequence of controlled, attention-demanding mechanisms of strategic semantic retrieval and encoding. Experiment 1 analysed the effect of presentation rate, with slow presentations being assumed to benefit strategic, time-dependent semantic encoding. Experiments 2 and 3 provided a more direct test of the strategic hypothesis by introducing three different concurrent attention-demanding tasks. Although Experiment 1 showed a larger concreteness effect with slow presentations, the following two experiments yielded strong evidence against the strategic hypothesis. Limiting available attention resources by concurrent tasks reduced global memory performance, but the concreteness effect was equivalent to that found in control conditions. We conclude that semantic effects in STM result from automatic semantic encoding and provide tentative explanations for the interaction between the concreteness effect and the presentation rate.     

Strategic encoding and retrieval processes in verbal recall among middle-aged and older adults

The authors used an analysis of individual differences to examine the role of executive control in strategic encoding and retrieval in verbal recall. Participants enrolled in the Louisiana Healthy Aging Study completed measures of working memory (WM), cognitive status, vocabulary, and free recall of words. Indices of clustering in free recall were calculated to permit inferences on strategic encoding and retrieval processes. We hypothesized that WM would be more strongly associated with strategic encoding and retrieval metrics than vocabulary based on the assumption that successful remembering requires executive control in WM. Regression analyses, together with a variance portioning procedure, confirmed that WM had comparable levels of unique and shared variance with the strategic encoding and retrieval metrics, and both exceeded vocabulary. Theoretical and clinical implications of these data are considered, with the suggestion of future research in lifespan samples as opposed to exclusively young adult or older adult samples.