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W Wippich

Publications and source records attributed to W Wippich.

At least 19 recordsLinked to original sources
PubMed1998

Effects of color on perceptual and conceptual tests of implicit memory.

Two experiments are reported that explore why recent investigations of implicit memory failed to find any effects of color information on test performance. In the first experiment, participants studied colored pictures as well as words printed in colored ink without any memory instructions. During the test phase, a verbal and a pictorial version of a color-choice task (a conceptual priming test) were compared to two perceptual tests (word-stem completion and picture-fragment identification). Similar and significant amounts of priming to color occurred in both color-choice tasks. The perceptual tests were found to be sensitive to changes in the stimulus-presentation mode from study to test, but stimuli remaining the same color and those changed to black-and-white did not differ in the priming scores. In the second experiment, a mild division of attention was introduced in the study phase. Once again, priming to color was observed only in the verbal version of a color-choice test and not in the word-stem completion test. Dividing attention did not decrease performance on both implicit tests, whereas an explicit test of color recall for studied pictures suffered from dividing attention at encoding. It is concluded that a perceptual attribute such as color may be represented and coded by conceptual processing. Furthermore, automatic (or not attention-demanding) encoding processes may suffice for later conceptual tests of implicit memory. Previous failures to find any effects of color information on implicit performance are attributed to the use of perceptual priming tests.

Color Perception↗
PubMed1996

Stress- and treatment-induced elevations of cortisol levels associated with impaired declarative memory in healthy adults.

Two studies investigated the association between cortisol levels and memory performance in healthy adults. In a first study, 13 subjects were exposed to a brief psychosocial laboratory stress ("Trier Social Stress Test") with a subsequent test of declarative memory performance. Results indicated a significant negative relationship between stress-induced cortisol levels and performance in the memory task, i.e. subjects with high cortisol response to the stressor showed poorer memory performance. In a second experiment it was investigated if cortisol, alone, i.e. independent of psychological stress, would also impair memory function. In this study, 40 healthy subjects received either 10 mg cortisol or placebo orally. One hour later they were tested for procedural and declarative memory and spatial thinking. Subjects who received cortisol showed impaired performance in the declarative memory and spatial thinking tasks but not in the procedural memory task. From these results we conclude that in healthy adults elevated free cortisol levels are associated with impaired memory function.

Adult↗
PubMed1996

Unconscious Gender Bias in Fame Judgments?

In two experiments the conditions of, and the processes leading to, gender biases in fame judgments were investigated. In Experiment 1, the gender bias was not reduced in a condition that alerted participants to the gender of the names. In Experiment 2, participants' sex-role orientation, but not their gender, was related to the gender bias. The process dissociation procedure was used in both experiments in an attempt to separate conscious and unconscious memory processes contributing to the gender bias. Using L. L. Jacoby's (1991) original measurement model there appeared to be evidence for unconscious influences on the gender bias in fame judgments. Unfortunately, this evidence disappeared when a model was used that takes guessing and, hence, response biases into account, which confirms that measurement models that ignore response biases in the process dissociation procedure may lead to erroneous conclusions.

Journal Article↗
PubMed1996

Investigating Fame Judgments: On the Generality of Hypotheses, Conclusions, and Measurement Models

In this article, we try to clarify some of the issues raised by S. C. Draine, A. G. Greenwald, and M. R. Banaji (1996) concerning our investigation into the gender bias in fame judgments (A. Buchner & W. Wippich, 1996). First, we did not test the general hypothesis and did not draw the general conclusion that Drain et al. suggest we did. Second, we did not reject M. R. Banaji and A. G. Greenwald's (1995) assumptions about the familiarity of male and female names in the fame judgment task, but we showed how one could have come to reject it using a widespread measurement model for the process dissociation procedure. Third, we argue that the processes which Draine et al. suggest should also be included in the measurement model we used are probably negligible, and if they are not, then the validity of the results of a number of fame judgment experiments must be called into question. In general, however, we agree with what seems to be the main message ofM. R. Banaji and A. G. Greenwald's (1995) research, namely, that social categories have to be considered whenever priming is investigated within a social domain.

Journal Article↗
PubMed1995

Priming on verbal perceptual tests: roles of lexical, surface, and conceptual processes.

According to a lexical-access hypothesis, priming on verbal-completion tests requires previous access to higher-order nodes such as morphemes or words. In two experiments, subjects studied words presented in printed color, either by reading the words or by naming the printed colors. In Experiment 2, some of the words were to be ignored in both study conditions. The words presented in Experiment 2 were either conceptually related or unrelated to each other. And the cues in the test phase for repeated targets were either printed in the studied color or in a different color. In both experiments, the word stems of nouns studied and of new targets were presented with word-completion instructions (implicit test of memory). Consistent with the hypothesis, the amount of priming obtained was greater in the reading than in the color-naming condition. The least amount of priming was observed for targets that were to be ignored at study. In addition, Experiment 2 showed considerable effects of surface similarity (i.e., stronger priming effects with cues whose color was not changed from the study to the test phase) and some effects of conceptual processing, as was indicated by different amounts of priming for unrelated and for related nouns. Because these two effects were observed with both types of study task, it is concluded that perceptual and conceptual processes may make independent contributions to priming effects in verbal perceptual tests. This conclusion modifies and extends the original hypothesis, according to which previous lexical access is required in order to obtain effects of perceptual or conceptual processes on the priming scores.

Adult↗
PubMed1995

[Priming effects in picture problems: preliminary solutions].

Two experiments explored whether picture puzzles are an adequate instrument to investigate implicit memory for pictorial information. During the testing phase, the subjects had to identify hidden figures in picture puzzles. In a preceding learning phase, the priming conditions were varied systematically. In the first experiment, some subjects had to solve picture puzzles in the learning phase, whereas others made esthetic judgments (global processing) or estimated the number of triangles in the picture puzzles (local processing). In the second experiment, the subjects inspected copies of figures that were hidden at testing, modified versions of these figures, or their names in the learning phase. In the first experiment, the subjects of the different encoding conditions showed comparable priming effects. Picture puzzles that had already been processed or seen during learning were solved more often than new ones. Interview data revealed that subjects in the local or global processing conditions did not identify hidden figures at encoding. Furthermore, these subjects could not discriminate between old and new picture puzzles in a final explicit test of recognition. Thus, nonconscious storage of perceptual information that is not semantically interpreted may be sufficient to evoke priming effects. In the second experiment, the subjects in the different encoding conditions showed reliable priming effects, too. The presentation of the duplicates at encoding produced the greatest amount of priming. Effects of verbal priming, however, indicate that the solution of picture puzzles is not based solely on perceptual information. Depending on the priming conditions at learning, the solution of picture puzzles may be based primarily on data-driven processing or may be guided more heavily by conceptual information. It is concluded that perceptual, lexical, and/or conceptual information can contribute to the solution of picture puzzles.

Adult↗
PubMed1994

[Motor and sensory effects of haptic experiences in implicit and explicit memory tests].

The present experiments explore the components (motor and/or sensory) underlying performance in implicit and explicit tests of memory for haptic information. In the first experiment, the encoding tasks and the test conditions were varied. During the encoding phase half of the subjects were blindfolded and explored real objects with their hands in order to answer questions about object properties (like form) as fast as possible (active exploration). The other subjects performed adequate hand movements without any sensory contact with the objects (motor encoding). At testing, for some subjects the active exploration task was repeated with old and with new objects. Other subjects who did not perform any hand movements based their judgments on sensory impressions only (passive touch). The results demonstrate reliable effects of implicit memory for haptic information, as revealed by faster reaction times to old than to new objects. However, priming effects were only obtained in the active touching test condition. This result was observed for both encoding tasks, that is, even for subjects who had only performed symbolic hand movements at encoding. Thus, the repetition of specific motor processes seems to underly the effects of repetition priming in active touch. In the second experiment, a passive touch paradigm was realized both at encoding and at test (sensory encoding). The priming effects observed under these conditions indicate that sensory processes can be relevant, too. Recognition performance was found to be influenced by other variables than measures of implicit memory. The results are discussed with respect to process-oriented and system approaches to implicit memory.

Adult↗
PubMed1994

[Effects of color on implicit and explicit memory tests].

We report two experiments that explore why recent investigations of implicit memory did not find any effects of color information on test performance. The argument that previous failures to find effects of repetition priming were due to an arbitrary association between objects and colors was found to be wanting. To the contrary, both experiments showed no or small effects of repetition for objects paired with their prototypical colors. A second argument according to which subjects attend to the colors at encoding did not fare much better. More importantly, however, we found strong effects of repetition priming with a conceptual implicit memory measure, whereas previous research had relied exclusively on perceptual tests of implicit memory. In both experiments, the subjects were asked to choose a suitable color for each object at testing. No instructions about remembering the objects were given. The results demonstrated strong preferences for the previously seen colors in the color-choice task. Furthermore, this effect was present to the same extent with picture objects and with object names, corroborating the conceptual nature of the implicit memory measure. Finally, we observed many functional dissociations with explicit measures of memory for color information, demonstrating implicit use of memory in the conceptual choice-test for colors.

Attention↗
PubMed1991

Haptic information processing in direct and indirect memory tests.

Effects of learning can show up in a direct, i.e., an explicit, way or they can be expressed indirectly, i.e., in an implicit way. It was investigated whether motor processes underlie effects of repetition priming in haptic information exploration. In the test phase, blindfolded subjects had to handle objects in order to answer questions as fast as possible about their properties (e.g., temperature, texture, weight, or form), exploring the object with their hands. Some of the objects were old ones (presented in a study phase); others were added as new objects to the test phase. In addition, recognition judgements were required. The results demonstrated reliable effects of repetition priming in terms of reaction times to old, in comparison with new, objects for subjects who had been treated the same way in the study phase (active touch). Passive touch at encoding or studying the names or the visible objects themselves did not lead to effects of repetition priming in the test phase. On the other hand, performing adequate hand movements during the study improved recognition memory. The role of motor processes in indirect and direct tests of memory is discussed and related to research on memory of action events.

Adult↗
PubMed1990

[Context-dependence of implicit and explicit memory characteristics].

The present experiments explore whether repetition priming in a word-stem completion task is context-dependent. In the first experiment, the environmental context was changed or remained constant at the testing stage. Implicit memory performance did not reveal any effects of environmental context. When tested by free recall, however, the same subjects showed an environmental congruency effect. On the other hand, effects of a change in presentation modality were restricted to implicit memory measures. In the second experiment, self-awareness was manipulated to create congruent or incongruent internal contexts at the testing stage. Performance on the word-stem completion task was seen to be influenced by internal contextual information. This pattern of results corroborates a processing account of implicit memory phenomena. Implicit and explicit expressions of memory utilize episodic information, but in a different way.

Adult↗
PubMed1990

[Understanding or feeling? Motor and sensory processes in recall of haptic experiences].

Effects of learning can show in a direct, i.e., explicit way, or they can be expressed indirectly, i.e., in an implicit way. It is investigated whether hepatic information shows implicit effect, and whether implicit haptic memory effects are based primarily on motor or on sensory memory components. In the first phase blindfolded subjects had to palpate objects in order to answer questions about the objects' distinct properties as fast as possible. In the following phase this task was repeated with the same objects and additional control items. Additionally, recognition judgements were required. Results demonstrate reliable effects of implicit memory for haptic information in terms of reaction times to old vs. new objects. Subjects who had to wear plastic gloves in the first stage showed comparable effects of repetition priming. Changing the questions--and, thus, hand movements--during the palpitation of objects known from the first stage, however, abolishes implicit memory expression. It is concluded, therefore, that implicit memory for haptic information is based on motor processes. On the other hand, explicit memory is hampered in subjects wearing gloves during the first phase, as revealed in terms of recognition performance while changing the questions about objects' properties has no effect on recognition judgements. Thus, explicit memory for haptic information seems to be based on the sensory processes when touching objects.

Concept Formation↗
PubMed1990

[Recall of odors: naming and autobiographical memories illustrate odor aftereffects].

In the study phase, subjects had to encode either odors or the names there of by generating autobiographical memories, by judging the quality of the food source of the odors, or by labeling responses to odors. At the testing stage, explicit and implicit olfactory memory performance was assessed. With recognition testing, the provision of odors at study improved performance. Furthermore, recognition depended on elaborative encoding conditions with olfactory stimuli only. Implicit memory was measured by the correctness and speed of labeling responses at the testing stage. Old odors were named more correctly and faster than new ones, but only if subjects had encoded odors in the study phase. These results demonstrate that implicit memory in naming odors depends on olfactory stimulus processing and is not a purely verbal priming effect. As a further measure of implicit memory, the speed of autobiographical memory productions was assessed. We registered shorter reaction times for old versus new odors. But again, this effect of implicit memory was restricted to conditions of odor pre-experiences in the study phase. We conclude that olfactory memory is based on different types of memory traces. Implicit memory measures may prove to be useful in isolating sensory and other attributes of olfaction that seem to be interacting in making explicit memory judgments.

Adult↗
PubMed1989

Implicit memory in spelling from word images.

A series of experiments is reported concerning implicit memory in imaginal processing. In the standard condition, subjects had to encode word images before spelling a word. The spelling task was repeated in the test phase with the same words and with additional control words. Spelling times were registered after the image encoding. Implicit memory has been detected if repeated words can be spelled faster than control words. Experiment 1 showed that levels of processing manipulations (such as the additional generation of meaning images at encoding or variations in word concreteness) favor explicit memory, but do not show up in implicit memory. Experiment 2 demonstrated that implicit memory disappears if spelling at encoding took place on visually present words. Experiment 3 investigated whether the focusing of specific letter positions within the image may contribute to the effect, but this was not found. According to a processing view that underlies our task analysis, implicit memory depends on transfer-appropriate processing and is attributed to processes of image encoding or generation and image reconstruction or regeneration.

Adolescent↗
PubMed1989

[Implicit and explicit memories of odors].

The present experiments explore whether there may be some forms of implicit memory for odors. In the first experiment, the elaborateness of olfactory encoding was varied at presentation. For (explicit) recognition memory testing we found positive effects of labeling responses to odors at encoding. Implicit memory measures (temporal and preference judgments) did not reveal reliable effects of prior odor presentation, however. The second experiment corroborated effects of levels of processing on r recognition memory. Again, perceptual or affective judgments remained insensitive for prior odor exposures. Implicit memory could only be detected with verbal measures at the testing stage (labeling accuracy or latency). These results are consistent with the proposal that odor information is represented at different levels of processing that are even with implicit memory measures only partly accessible.

Adult↗
PubMed1989

[Effect of divided attention on explicit and implicit aspects of recall].

If subjects have to form word images before spelling a word from the image, results of a repetition of the spelling test reveal a reliable priming effect: Old words can be spelled faster than comparable control words, reflecting a form of implicit memory. We investigated whether this kind of repetition priming remains stable under conditions of divided attention in the study phase. The subjects had to spell meaningful words, meaningless non-words, and non-words that were meaningful with a backward spelling direction (troper, for example). In the testing stage, recognition judgments as a form of explicit memory were required, too. Divided attention in the study phase had a negative effect on explicit memory, as revealed by performance on the recognition task, but had little effect on implicit memory, as revealed by performance on the repetition of the spelling test. A further dissociation between implicit and explicit memory showed up as meaningful words were recognized much better than non-words, whereas implicit memory was uninfluenced by the meaningfulness variable. The disadvantage of backward spellings was not reduced with non-words (like troper) spelled backwards. Finally, we analyzed the relations between spelling times and recognition judgments and found a pattern of dependency for non-words only. Generally, the results are discussed within processing-oriented approaches to implicit memory with a special emphasis on controversial findings concerning the role of attention in different expressions of memory.

Adult↗