Acquisition and transfer of new verbal information in amnesia: Retrieval and neuroanatomical constraints.

Four experiments examined new associative learning in amnesia by contrasting the performance of 2 amnesic participants—1 (C.C.) with basal forebrain damage and the other (R.H.) with medial temporal lobe damage—and 3 controls. Both amnesic individuals were severely impaired on explicit memory measures but showed intact perceptual priming. On the new associations measures, only C.C., not R.H., exhibited learning by producing correct targets (HIJACKER) in the absence of perceptual cues for them (e.g., STAFF shot ??? ). When the perceptual cue (e.g., MEDICINE cured-I-C-P) was provided, both C.C. and R.H. showed learning. Transfer to information containing conceptually related targets (e.g., TERRORIST or BELCH) was reliably observed only in C.C. This finding was replicated with further reduction in perceptual overlap across original (LIGHTNING torched JUNGLE) and transfer (LIGHTNING burned WILDERNESS) sentences. Together, these findings delineate the role of experimental conditions, severity of amnesia, and different neuroanatomical structures in mediating new verbal learning in amnesia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Plasticity of memory for new learning in very old age: A story of major loss?

Longitudinal survivors of the Berlin Aging Study (N = 96, mean age = 84 years, range 75-101 years) were instructed and trained in a mnemonic skill to examine plasticity of episodic memory performance in very old age. Performance gains after mnemonic instruction were modest, and most individuals were unable to further enhance their performance during 4 sessions of mnemonic practice. Whereas the proportion of variance explained by measures from the broad fluid-ability domain (e.g., perceptual speed) increased with training, the proportion of variance explained by crystallized-ability domain (e.g., word knowledge) and sociobiographical variables decreased. Furthermore, prior 6-year longitudinal changes (loss) in perceptual speed predicted individual differences in plasticity. Results suggest that aging-induced biological factors are a prominent source of individual differences in cognitive plasticity in very old age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychophysics of the McGurk and other audiovisual speech integration effects.

When the auditory and visual components of spoken audiovisual nonsense syllables are mismatched, perceivers produce four different types of perceptual responses, auditory correct, visual correct, fusion (the so-called McGurk effect), and combination (i.e., two consonants are reported). Here, quantitative measures were developed to account for the distribution of the four types of perceptual responses to 384 different stimuli from four talkers. The measures included mutual information, correlations, and acoustic measures, all representing audiovisual stimulus relationships. In Experiment 1, open-set perceptual responses were obtained for acoustic /bɑ/ or /lɑ/ dubbed to video /bɑ, dɑ, gɑ, vɑ, zɑ, lɑ, wɑ, eɑ/. The talker, the video syllable, and the acoustic syllable significantly influenced the type of response. In Experiment 2, the best predictors of response category proportions were a subset of the physical stimulus measures, with the variance accounted for in the perceptual response category proportions between 17% and 52%. That audiovisual stimulus relationships can account for perceptual response distributions supports the possibility that internal representations are based on modality-specific stimulus relationships. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Further explorations of perceptual speed abilities in the context of assessment methods, cognitive abilities, and individual differences during skill acquisition.

Measures of perceptual speed ability have been shown to be an important part of assessment batteries for predicting performance on tasks and jobs that require a high level of speed and accuracy. However, traditional measures of perceptual speed ability sometimes have limited cost-effectiveness because of the requirements for administration and scoring of paper-and-pencil tests. There have also been concerns about the validity of previous computer approaches to administering perceptual speed tests (e.g., see Mead & Drasgow, 1993). The authors developed two sets of computerized perceptual speed tests, with touch-sensitive monitors, that were designed to parallel several paper-and-pencil tests. The reliability and validity of the tests were explored across three empirical studies (N = 167, 160, and 117, respectively). The final study included two criterion tasks with 4.67 and 10 hours of time-on-task practice, respectively. Results indicated that these new measures provide both high levels of reliability and substantial validity for performance on the two skill-learning tasks. Implications for research and application for computerized perceptual speed tests are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Failures to ignore entirely irrelevant distractors: The role of load.

In daily life (e.g., in the work environment) people are often distracted by stimuli that are clearly irrelevant to the current task and should be ignored. In contrast, much applied distraction research has focused on task interruptions by information that requires a response and therefore cannot be ignored. Moreover, the most commonly used laboratory measures of distractibility (e.g., in the response-competition and attentional-capture paradigms), typically involve distractors that are task relevant (e.g., through response associations or location). A series of experiments assessed interference effects from stimuli that are entirely unrelated to the current task, comparing the effects of perceptual load on task-irrelevant and task-relevant (response competing) distractors. The results showed that an entirely irrelevant distractor can interfere with task performance to the same extent as a response-competing distractor and that, as with other types of distractors, the interfering effects of the irrelevant distractors can be eliminated with high perceptual load in the relevant task. These findings establish a new laboratory measure of a form of distractibility common to everyday life and highlight load as an important determinant of such distractibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging, source memory, and emotion.

In 2 experiments we assessed younger and older adults' ability to remember contextual information about an event. Each experiment examined memory for 3 different types of contextual information: (a) perceptual information (e.g., location of an item); (b) conceptual, nonemotional information (e.g., quality of an item); and (c) conceptual, emotional information (e.g., safety of an item). Consistent with a large literature on aging and source memory, younger adults outperformed older adults when the contextual information was perceptual in nature and when it was conceptual, but not emotional. Age differences in source memory were eliminated, however, when participants recalled emotional source information. These findings suggest that emotional information differentially engages older adults, possibly evoking enhanced elaborations and associations. The data are also consistent with a growing literature, suggesting that emotional processing remains stable with age (e.g., Carstensen & Turk-Charles, 1994, 1998; Isaacowitz, Charles, & Carstensen, 2000). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit memory in Alzheimer's disease: A meta-analysis.

Meta-analysis was performed on 33 articles (36 experiments involving 564 Alzheimer's disease [AD] patients and 592 controls). Overall, AD patients were significantly impaired on implicit memory tests, r?=?.163 (a difference of .329 SDs from normal performance). They were impaired on nonverbal tests (e.g., fragmented pictures), word stem completion, classical conceptual tests (e.g, free association), and on word-based perceptual tests with long delays. However, they performed normally on word-based perceptual tests (e.g., perceptual identification of words) with short study test delays. They also performed normally on word stem completion if they were older than 75, possibly because their age-matched controls were also impaired. These results are neither qualified by study list length nor patient mental status. None of the theories in the field is compatible with the results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and qualitative characteristics of memories for perceived and imagined complex events.

Older and younger adults' memory for perceived and imagined events was examined with a procedure in which everyday situations are simulated in the laboratory. Subjects perceived some situations and imagined others. Later, they were asked to rate their memory for various aspects of these situations (e.g., amount of perceptual detail, thoughts and feelings). A recall test followed the ratings. On the rating scale, for both perceived and imagined events, older subjects reported better memory for their thoughts and feelings than did younger subjects. In addition, on the recall test, older subjects produced more thoughts and feelings than did younger subjects, whereas younger subjects produced more perceptual and spatial information. These results suggest that older subjects may not inhibit personal information (e.g., thoughts and feelings), and this information may interfere with memory for other aspects of information, such as perceptual and contextual details (Hasher & Zacks, 1988). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interactive Visual and Postvisual Processes and Their Roles in Form-Specific Memory.

Effects of depth of encoding on form-specific memory were examined. After viewing words (e.g., "bear") presented centrally during initial encoding, participants completed word stems (e.g., "BEA") presented laterally and pattern masked during subsequent test. When the encoding task was perceptual, letter-case specific memory was not observed, unlike in previous experiments without pattern masking. However, when the encoding task required both perceptual and conceptual processing, letter-case specific memory was observed in direct right-hemisphere, but not in direct left-hemisphere, test presentations, like in previous studies without pattern masking. Results were not influenced by whether stems were completed to form the first words that came to mind or words explicitly retrieved from encoding. Depth of encoding may influence form-specific memory through interactive processing of visual and postvisual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of stimulus comparison in human perceptual learning: Effects of distractor placement.

Within-subjects procedures were used to assess the influence of stimulus comparison on perceptual learning in humans. In Experiment 1, participants received intermixed (A, A′, A, A′,…) or blocked (B, B,…, B′, B′,…) exposure to pairs of similar female faces. In a subsequent same/different discrimination task, participants were more accurate when the test involved A and A′ than when it involved B and B′ (or novel faces: C and C′). This perceptual learning effect was reduced by placing a visual distractor (*: either another face or a checkerboard) between successive presentations of the faces during the exposure stage (e.g., A – * – A′). The attenuation of the intermixed versus blocked difference was particularly marked when faces were used as the distractor. In Experiment 2, this reduction in perceptual learning was more marked when * was positioned between the pairs of intermixed faces (i.e., A – * – A′) than when it preceded and succeeded those faces (i.e., * – A – A′ – *). These results provide the first direct evidence that the opportunity to compare stimuli plays a causal role in supporting perceptual learning. They also support the specific view that perceptual learning reflects an interaction between a short-term habituation process, that ordinarily biases processing away from the frequently presented common elements and toward their less frequently presented unique elements, and a long-term representational process that reflects this bias. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Level of processing affects priming in word fragment completion.

In 4 experiments, Ss studied words under learning conditions that promoted semantic or physical processing. An implicit word fragment completion test was administered (e.g., complete l ph t for elephant). When semantic and physical study conditions were manipulated between Ss (Exps 1 and 3) or within Ss in a blocked fashion (Exps 3 and 4), significant levels of processing (LOP) effects were obtained. When semantic and physical conditions were presented in a mixed list (Exps 2, 3, and 4), the LOP effect was smaller and not significant. A survey of the literature on LOP effects in implicit perceptual tests revealed that priming in these tests was consistently greater in the semantic than physical condition, with reports of statistically significant LOP effects. These findings contradict the widely held notion that LOP does not affect priming in implicit perceptual tests and have implications for contemporary accounts of performance in implicit and explicit measures of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult age differences in recall of performed and nonperformed items.

Memory for performed cognitive activities (e.g., psychometric tests of intelligence), for performed brief actions (e.g., hand wave), and for nonperformed items (e.g., written words) was assessed for 102 older and 101 younger adults. Although enactment improved recall, the beneficial effects of enactment were the same for both age groups. In fact, more than 80% of the age-related variance in memory for performed items was shared with memory for nonperformed items. Working memory and perceptual speed were important to the age differences in memory for both types of items. Performed and nonperformed items showed different serial position effects. However, the correlation between memory for the 2 types of items was high, especially for older adults, suggesting that the 2 types of memory share many common processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The course of pregnancy complicated by bulimia.

Presents the cases of 3 women (aged 23, 28, and 31 yrs) who became pregnant during the course of eating disorders group therapy. Contrary to previous reports (e.g., J. H. Lacey and G. Smith; see record 1988-27049-001), Ss revealed in semi-structured interviews that they did not reduce bingeing and purging behaviors, or if they did, they replaced them with other potentially dangerous weight-control measures. Findings underscore the need to identify and directly address pregnant bulimics' cognitive and perceptual distortions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What does visual agnosia tell us about perceptual organization and its relationship to object perception?

The authors studied 2 patients, S.M. and R.N., to examine perceptual organization and its relationship to object recognition. Both patients had normal, low-level vision and performed simple grouping operations normally but were unable to apprehend a multielement stimulus as a whole. R.N. failed to derive global structure even under optimal stimulus conditions, was less sensitive to grouping by closure, and was more impaired in object recognition than S.M. These findings suggest that perceptual organization involves a multiplicity of processes, some of which are simpler and are instantiated in lower order areas of visual cortex (e.g., collinearity). Other processes are more complex and rely on higher order visual areas (e.g., closure and shape formation). The failure to exploit these latter configural processes adversely affects object recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental sex differences in global-local perceptual bias.

Previous developmental studies have indicated that boys tend to perform better than girls on tasks associated with the right hemisphere (e.g., spatial tasks), whereas girls perform better on tasks associated with the left hemisphere (e.g., verbal tasks). Extending this body of literature to what is known about hemispheric specialization of visuospatial processing, we predicted that boys would be more global than girls in their perception of visual hierarchical stimuli. Forty girls and 39 boys between the ages of 4 and 12 years were administered a perceptual judgment task previously used by Kimchi and Palmer (see record 1983-02534-001). Boys were significantly more global in their perceptual judgments than girls at all ages. Younger children of both sexes were less global than older children. Results were consistent with developmental models that suggest an early left-hemisphere advantage for girls and a right-hemisphere advantage for boys. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does similarity make a difference? Predicting cohesion and attendance behaviors within exercise group settings.

In this study, we assessed the ability of perceptual surface-level (i.e., observable qualities such as age and physical condition) and deep-level (i.e., nonobservable qualities such as attitudes and values) similarity to predict cohesion and attendance within exercise groups. Following the 2nd class of their respective programs, participants (N = 273) from 46 registered group-based exercise programs completed perceptual measures of surface-level similarity, deep-level similarity, social cohesion, and task cohesion. Following the 8th class of these programs, attendance data were collected. Perceptions of deep-level similarity were found to predict task cohesion. In contrast, perceptions of surface-level similarity were found to predict social cohesion and program attendance. Taken together, these results suggest that perceptions of surface-level and deep-level similarity may have noteworthy implications for involvement within group-based exercise programs. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Bilingual lexical access in context: Evidence from eye movements during reading.

Current models of bilingualism (e.g., BIA+) posit that lexical access during reading is not language selective. However, much of this research is based on the comprehension of words in isolation. The authors investigated whether nonselective access occurs for words embedded in biased sentence contexts (e.g., A. I. Schwartz & J. F. Kroll, 2006). Eye movements were recorded as French–English bilinguals read English sentences containing cognates (e.g., piano), interlingual homographs (e.g., coin, meaning corner in French), or matched control words. Sentences provided a low or high semantic constraint for target-language meanings. Both early-stage comprehension measures (e.g., first fixation duration, gaze duration, and skipping) and late-stage comprehension measures (e.g., go-past time and total reading time) showed significant cognate facilitation and interlingual homograph interference for low-constraint sentences. For high-constraint sentences, however, only early-stage comprehension measures were consistent with nonselective access. There was no evidence of cognate facilitation or interlingual homograph interference for late-stage comprehension measures. Thus, nonselective bilingual lexical access at early stages of comprehension is rapidly resolved in semantically biased contexts at later stages of comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual Interactions Between Bilaterally Presented Words: What You Get Is Often Not What You See.

Bilateral presentations of words, 1 in the left visual hemifield (LVF) and 1 in the right (RVF), are used widely in studies of hemispheric asymmetry. However, although words shown centrally (i.e., nonlaterally) produce perceptual interactions in which 1 word alters the perceived identity of the other, perceptual interactions between bilaterally presented words have never been reported. To investigate this issue, the authors used brief, bilateral displays of words (e.g., romp-ramp) presented simultaneously. An eye tracker and forced-choice task ensured appropriate presentation and testing. Report accuracy was greatest for RVF words. However, this was accompanied by perceptual interactions that occurred almost exclusively in responses to LVF words, indicating that RVF words often altered the perceived identity of LVF words but not vice versa. (PsycINFO Database Record (c) 2010 APA, all rights reserved)