Associative learning and recognition memory in alcoholic Korsakoff patients.

Association learning and recognition memory were examined in 8 male alcoholic Korsakoff patients (mean age 58 yrs), and in the following 4 groups of 10 men: non-Korsakoff alcoholics (mean age 59 yrs), nonalcoholic controls (mean age 64 yrs), younger alcoholics (mean age 36 yrs), and nonalcoholic controls (mean age 37 yrs). The tasks were modeled after those used for testing memory functioning in nonhuman primates. Association learning, defined as the ability to distinguish rewarded from equally familiar nonrewarded visual stimuli, was impaired in Korsakoff patients. Korsakoff patients also were impaired on recognition memory—the ability to discriminate familiar from novel items. Results support the view of loss of multiple memory functions in alcoholic amnesia. An effect of aging was indicated by differences in performance levels between younger and older groups of non-Korsakoff participants, although the latter were superior to the Korsakoff patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The recognition of visual configuration and identity information by children and adults.

The tendency to rely on and the ability to remember configuration and identity information were examined in Exp I with 24 kindergartners, 3rd, and 6th graders, and paid graduate students and university employees. Ss saw, tachistoscopically, arrays of 4 Hebrew letters and, in one condition, made recognition choices between 2 incorrect arrays, one of which differed from the stimulus by items and the other by configuration. In 2 other conditions in which accurate response was permitted, ability to use configuration and item information independently was tested. All Ss tended to rely more on configuration than on identity information and were better able to use configuration than identity information. In a 2nd experiment with 19 Ss from the same age-groups as Exp I, it was established that the items could be remembered under explicit instructions to remember items and ignore configuration. By altering the configuration of items it was possible to produce item recognition decrements in younger, but not older, Ss. It is concluded that development aids visual processing, particularly through a functional integration of systems for handling identity and spatial information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual recognition in chronic and acute schizophrenics.

Compared schizophrenic and normal groups on their speed in recognizing the identity of pictorial stimuli which gradually came into sharper focus from an initially blurred appearance. The chronic schizophrenic group (N = 20) showed slower recognition than the acute schizophrenic (N = 20) or normal groups (N = 40), but the groups did not differ in amount of prerecognition hypotheses or time of 1st response. The differences in perceptual recognition speed seem related to certain clinical differences between the acute and chronic schizophrenic, particularly with regard to the impact of external perceptual stimuli vs. internally generated ideation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual priming of proper names in young and older normal adults and a patient with prosopanomia.

The purpose of this study was to determine if normal participants and a patient with prosopanomia can be perceptually primed for proper names. To this end, 2 experiments were conducted. In Experiment 1, normative data were collected on 4 proper-name priming tasks. The variables of levels of processing at encoding and age were manipulated. Robust priming results were obtained that were not influenced by either of these variables. The results of Experiment 2 indicated that prosopanomic patient, N.G., demonstrated normal repetition priming, despite her marked impairment in deliberate retrieval of person and city names. These results are interpreted in terms of a dissociation between explicit and implicit memory for proper names and suggest that the deficit in prosopanomia only involves deliberate access to the name; access to presemantic representations of the visual word form remains intact. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the problem of selection in short-term visual (iconic) memory.

Discusses methodological and theoretical questions concerning the problem of selection in visual short-term memory. Data from 2 previously published experiments were reanalyzed and an additional experiment with 36 undergraduates was performed. There is no evidence in any of these experiments to support the idea that partial report is more accurate than whole report or that selection occurs in visual memory. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual processes in matching and recognition of complex pictures.

The role of perceptual feature sampling in speeded matching and recognition was explored in 4 experiments. Experiments 1-3 involved a perceptual matching task with pictures of various objects and scenes. In Experiments 2 and 3, same-different judgments were given under time pressure. The main objective of the matching task was to obtain measures of the perceptual processing rates of different object features. Experiment 4 was an old-new recognition experiment, in which the same stimuli as those in the matching task were used. Response signals were used to limit processing time in the recognition task. The results demonstrated that it is possible to predict speeded recognition performance from performance in perceptual matching. A simple stochastic feature-sampling model provides a unified account of the data from the 4 experiments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual units in the acquisition of visual categories.

A series of experiments provided evidence that the representational structure of categories comprising dot patterns is based on pattern parts and pattern configuration rather than on pattern elements. Similarity judgments and postacquisition classification data could not be explained in terms of element-level perceptual units, even for categories of dot patterns with 7 of their 8 dots in the exact same relative location. The importance of higher order perceptual units was indicated by evidence that long-term retention of information specific to previously learned category exemplars, which is typical of natural objects, can also be obtained for artificial dot patterns, providing their structure reflects perceptual characteristics identified in Tversky and Hemenway's (1984) study of natural objects: Members of the same category had to be perceptually distinctive at the pattern configuration level and perceptually similar at the level of pattern parts. The level of within-category similarity for a set of categories (relative to between-categories similarity) did not predict whether item-specific information would be retained; long-term retention appears to require both within-category similarity and dissimilarity, but at different levels of perceptual structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of visual and auditory distractors on learning disabled and normal children's recognition memory performance.

Investigated whether distractibility in learning disabled (LD) children could be predicted on the basis of diagnosed visual and auditory learning deficits. 26 children in Grades 2–4 were classified as having visual or auditory reading disorders on the basis of the Illinois Test of Psycholinguistic Abilities. They and 17 normally achieving children from the same grades performed visual and auditory recognition memory tasks with visual or auditory distractors presented on 80% of the trials. Analysis of error frequencies revealed that with distractors, Ss in the 2 LD groups made more errors and did not improve over trials as much as control Ss. However, the predicted interaction between learning disability modality and task or distractor modality did not obtain. Rather, all 3 S groups made more errors when task and distractor were in the same modality. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Syllable coding in printed-word recognition by children and adults.

Studied phonological coding in printed-word recognition in English by examining the use made of syllable information by skilled and less skilled readers in 2 experiments using 32 2nd graders and 81 undergraduates. Stimuli were bisyllabic frequent nouns. Syllable coding was used by the less-skilled 2nd graders but not by either the better 2nd graders or adults in lexical decision tasks. However, adults did make use of syllable information when the direct use of letter information was slowed by presenting items in alternating upper- and lowercase letters. Differences between children and adults in their use of the syllable information in pseudowords are interpreted as indicating that for skilled adult readers, the major focus of activity in word recognition is at the letter level. For immature readers, the process of word recognition is less analytic and involves a more extensive lexical search based on a reduced amount of letter information. The results are discussed in terms of an interactive model of reading. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual depth synthesis in the visual system as revealed by selective adaptation.

Selective adaptation was used to determine the degree of interactions between channels processing relative depth from stereopsis, motion parallax, and texture. Monocular adaptations with motion parallax or binocular stationary adaptation caused test surfaces, viewed either stationary binocularly or monocularly with motion parallax, to appear to slant in the opposite direction compared with the slant initially adapted to. Monocular adaptations on frontoparallel surfaces covered with a pattern of texture gradients caused a subsequently viewed test surface, viewed either monocularly with motion parallax or stationary binocularly, to appear to slant in the opposite direction as the slant indicated by the texture in the adaptation condition. No aftereffect emerged in the monocular stationary test condition. A mechanism of independent channels for relative depth perception is dismissed in favor of a view of an asymmetrical interactive processing of different information sources. The results suggest asymmetrical inhibitory interactions among habituating slant detector units receiving inputs from static disparity, dynamic disparity, and texture gradients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Affective tone and visual recognition thresholds.

"These findings clearly confirm the results of those studies that have found no differences in recognition thresholds for stimulus words of purportedly differential affective value when the relative frequency of the stimulus words is controlled." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual information and attentional constraints in visual search of collision events.

This study examined the detection of collision events when multiple moving objects were present in the scene. Observers were presented with displays simulating a 3-D environment with multiple moving objects. The authors examined the ability of observers to detect collisions using a signal-detection paradigm and a visual search paradigm. The results indicated that, overall, observers were quite accurate at detecting collisions. Observers used both expansion information and static position to detect collisions, with expansion information being the more important source. Singleton search conditions were not processed in parallel, and conjunction search conditions had poorer performance than singleton search conditions. In addition, reaction times were greater for target-present trials as compared with target-absent trials. The results are interpreted in terms of 4 visual search hypotheses for collision detection when multiple moving objects are present. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual specificity and implicit auditory priming in older and younger adults.

Age differences in perceptual specificity for implicit auditory priming were examined in 3 experiments. All 3 experiments began with a study phase during which participants rated words based on perceptual (shallow encoding) or semantic (deep encoding) attributes. After the study phase, participants were asked to identify filtered versions of repeated and new words (implicit test) and then to make old/new recognition judgments (explicit test). In contrast to earlier findings (D. L. Schacter, B. Church, & D. M. Osowiecki, 1994), older and younger adults were equally sensitive to study-to-test changes in speaking rate (Experiment 1), fundamental frequency (Experiment 2), and voice (Experiment 3). Explicit memory, in contrast, was significantly poorer for older adults but was minimally affected by changes in surface features. Findings from the study are discussed with respect to their implications for establishing the mechanisms mediating perceptual specificity and for their importance in understanding age-related changes in implicit memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional demands of visual word recognition.

Becker's (1976, 1979, 1980, 1985; Becker & Killion, 1977; Eisenberg & Becker, 1982) verification model was used as a framework to investigate the attentional demands of word recognition. In two experiments, a lexical decision task and an auditory probe task were performed in single- and dual-task conditions. Responses to probes were divided into detection and movement measures that indexed the demands of recognition and response output, respectively. In Experiment 1, single- to dual-task decrements in probe detection performance were larger during low-frequency as compared with high-frequency trials. This finding indicates that the attentional demands of word recognition vary with word frequency. These findings were replicated in Experiment 2, which was designed to separate a response compatibility and a capacity interpretation of the results. The findings are interpreted within Becker's verification model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verbosity and emotion recognition in older adults.

Previous research suggests that older adults are more verbose than young adults and that general inhibitory difficulties might play a role in such tendencies. In the present study of 60 young adults and 61 older adults, the authors examined whether verbosity might also be related to difficulty deciphering emotional expressions. Measures of verbosity included total talking time, percentage of time spent on-topic, and extremity of off-topic verbosity. Over all 3 measures, older men and women were significantly more verbose than young men and women. Older men's (but not older women's) verbosity was related to poorer emotion recognition, which fully mediated the age effect. The results are consistent with the idea that older men who talk more do so, in part, because they fail to decipher the emotional cues of a listener. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transformations in the recognition of visual forms.

Conducted 3 experiments in which Ss were required to learn to recognize 4 flexible plastic shapes photographed on different backgrounds from different angles. Slides were designated as either prototypes (photographed from overhead on a black background), cued (photographed from many angles on a definite background, e.g., a chair), or uncued (the cued photographs placed on a black background). Ss were 80 undergraduates in Exp I, 80 16-24 yr olds in Exp II, and 43 undergraduates in Exp III. Variables investigated were (a) order, amount, and type of training (prototype, cued, or uncued); (b) type of training instructions (Ss were told either that there were 4 classes of objects or 4 objects viewed from various backgrounds); and (c) presence or absence of context in training or testing (background which gave cues to transformation). Results indicate that (a) type of training had a significant effect on performance; (b) the presentation of uncued test slides before cued ones decreased performance on the cued slides, while cued slides presented first facilitated performance on the uncued slides; and (c) the presence of context in training significantly increased rates of pattern learning and success in recognizing new material. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Morphological and orthographic similarity in visual word recognition.

The differential impact of orthographic and morphological relatedness on visual word recognition was investigated in a series of priming experiments in Dutch and German. With lexical decision and naming tasks, repetition priming and contiguous priming procedures, and masked and unmasked prime presentation, a pattern of results emerged with qualitative differences between the effects of morphological and form relatedness. With lexical decision, mere orthographic similarity between primes and targets (e.g., keller–KELLE, cellar–ladle) produced negative effects, whereas morphological relatedness (e.g., kellen–KELLE, ladles–ladle) consistently resulted in facilitation. With the naming task, positive priming effects were found for morphological as well as for mere form similarity. On the basis of these results, a model of the lexicon is proposed in which information about word form is represented separately from morphological structure and in which processing at the form level is characterized in terms of activation of, and competition between, form-related entries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual and motor inhibition in adolescents/young adults with childhood-diagnosed ADHD.

Objective: This study examined perceptual and motor inhibition in a longitudinal sample of adolescents/young adults who were diagnosed with ADHD in childhood, and as a function of the relative persistence of ADHD. Method: Ninety-eight participants diagnosed with ADHD in childhood were reevaluated approximately 10 years later. Eighty-five never-ADHD controls similar in age, IQ, sociodemographic background, and gender distribution served as a comparison group. Participants were administered a psychiatric interview and the Stimulus and Response Conflict Tasks (Nassauer & Halperin, 2003). Results: Participants with childhood ADHD demonstrated slower and less accurate responses to both control and conflict conditions relative to the comparison group, as well as more variable responses in both conditions of the motor inhibition task; there was no specific effect of childhood ADHD on perceptual or motor inhibition. ADHD persisters and partial remitters did not differ in overall accuracy, speed or variability in responding, but relative to partial remitters, persisters demonstrated greater slowing in response to perceptual conflict. Conclusions: These findings are consistent with theories positing state regulation, but not inhibitory control deficits in the etiology of ADHD, and suggest that improved perceptual inhibition may be associated with better outcome for ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Static and dynamic visual sensitivity in older adults.

Many visual changes accompany the aging process, even in the absence of known visual pathology. One such change which has attracted recent attention is that "normal" older adults, on average, exhibit diminished contrast sensitivity (CS). This loss is not of a general nature, but rather is restricted to intermediate and higher spatial frequencies. Age-related decline in CS has been attributed to both optical (e.g., retinal illuminance, light scatter) and neural factors (e.g., cell loss in higher-order neurons). Three experiments evaluated CS in adults of varying ages. These experiments were intended to 1) establish provisional age norms for the Vistech Contrast Test System, a recently developed method for CS evaluation; 2) assess the convergent and construct validity of the Vistech charts against an optical/neural model of age-related differences in spatial vision; and 3) determine the degree to which these age-deficits in CS were magnified in a dynamic contrast sensitivity (DCS) task where bifoveal fixation requires accurate smooth pursuit. Results demonstrate that the Vistech charts appear to possess good convergent validity with respect to age differences in spatial vision. In addition to declines in spatial vision, older adults are less able to smoothly pursue a moving stimulus. This decline in smooth pursuit accuracy suggested that age differences in CS would be magnified when the elderly were required to discern contrast in a moving stimulus. Two studies have produced results which are consistent with this argument. (PsycINFO Database Record (c) 2010 APA, all rights reserved)