Implicit and explicit memory for visual patterns.

The article reports an investigation of implicit and explicit memory for novel, visual patterns. Implicit memory was assessed by a speeded perception task, and explicit memory by a four-alternative, forced-choice recognition task. Tests were given either immediately after testing or 7 days later. The results suggest that a single exposure of a novel, nonverbal stimulus is sufficient to establish a representation in memory that is capable of supporting long-lived perceptual priming. In contrast, recognition memory showed significant loss over the same delay. Performance measures in the two tasks showed stochastic independence on the first trial after a single exposure to each pattern. Finally, a specific occurrence of a previously studied item could be retrieved from explicit memory but did not affect the accuracy of perception in the implicit memory test. The results extend the domain of experimental dissociations between explicit and implicit memory to include novel, nonverbal stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory bias in anxiety.

Previous investigations of recall and recognition for threatening information in clinically anxious subjects have yielded equivocal results. The present study contrasts implicit (word completion) with explicit (cued recall) memory and shows that indices of bias for emotional material derived from the two types of memory are independent of one another. The explicit measure was correlated with trait anxiety scores, but did not clearly distinguish between subjects with clinical anxiety states and normal control subjects. On the implicit memory measure, clinically anxious subjects produced more threat word completions, but only from a set to which they had recently been exposed. These results are taken as evidence that internal representations of threat words are more readily or more persistently activated in anxiety states, although they are not necessarily better elaborated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory in young and older adults.

In three experiments, young and older adults were compared on both implicit and explicit memory tasks. The size of repetition priming effects in word completion and in perceptual identification tasks did not differ reliably across ages. However, age-related decrements in performance were obtained in free recall, cued recall, and recognition. These results, similar to those observed in amnesics, suggest that older adults are impaired on tasks which require conscious recollection but that memory which depends on automatic activation processes is relatively unaffected by age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit memory for pictures in amnesia: Role of etiology and priming task.

This study examined the performance of patients with Korsakoff and non-Korsakoff amnesia on tests of picture priming. Both groups showed intact priming on a picture-naming task but impaired priming on a fragment-completion task when fragmented pictures were presented at study. When whole pictures were presented at study, patients with non-Korsakoff amnesia showed intact priming, but Korsakoff patients' priming remained impaired. Both groups performed equally poorly on a picture-recognition task. It is concluded that non-Korsakoff patients show intact picture priming when explicit memory does not contaminate fragment-completion performance. Korsakoff patients, in contrast, show a selective impairment in the perceptual processes that mediate picture-fragment completion priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory for shape, body weight, and food-related words in patients with anorexia nervosa and nondieting controls.

Twelve patients with anorexia nervosa and 12 control participants watched a series of 64 words. There were 4 word types: anorexia related, positive, negative, and neutral. The last 3 types were anorexia unrelated. Anorexia-related words had the same affective valence as the neutral control words. Next, the participants completed an explicit memory test ( cued recall ) and an implicit memory test (word stem completion). Results showed a strong explicit memory bias for anorexia-related words for patients with anorexia nervosa but not for nondieting controls. There was no evidence for a similar bias in implicit memory. Results are discussed in the context of cognitive biases in psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual specificity of auditory priming: Implicit memory for voice intonation and fundamental frequency.

Five experiments explored the effect of acoustic changes between study and test on implicit and explicit memory for spoken words. Study-test changes in the speaker's voice, intonation, and fundamental frequency produced significant impairments of auditory priming on implicit tests of auditory identification and stem completion but had little or no effect on explicit recall and recognition tests (Exps 1–4). However, study-test changes in overall decibel level had no effect on priming on an auditory stem-completion test or on cued-recall performance (Exp 5). The results are consistent with the idea that fundamental frequency information is represented in a perceptual representation system that plays an important role in auditory priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory in individuals with mental retardation

Students with and without mental retardation from three age groups were compared on implicit and explicit memory tasks. Consistent with previous research on intelligence-related differences in controlled and automatic processes, students without mental retardation performed better than those with mental retardation on the explicit memory task, but there was no difference between groups on the implicit memory task. For both groups implicit and explicit memory increased from age 6 to 8 to age 10 to 12, but did not significantly increase to age 15 to 17. Because implicit memory appears to be a relative strength for students with mental retardation, we suggest further exploration into broader types of implicit processes that may be useful in training situations.     

Implicit priming of alcohol expectancy memory processes and subsequent drinking behavior.

Expectations about the effects of alcohol have been modeled as stored memories. This study tested the memory view for investigating the processes that influence drinking. Strategies taken from recent memory research were used to implicitly prime drinking. Consequent effects on consumption of a commercial nonalcoholic beer were measured. Participants were led to believe this beer contained alcohol. Eighty undergraduate women (n?=?20 per cell) participated in 2, apparently unrelated, studies. A 2?×?2 factorial design simultaneously varied videotaped primes (bar setting or neutral video) with semantic primes (expectancy or neutral words). Women exposed to unobtrusive alcohol primes of either type drank significantly greater amounts (p?     

Implicit and explicit memory retrieval within and across the disconnected cerebral hemispheres.

The authors report that the divided right and left cerebral hemispheres are both adept at priming, a type of implicit memory, and that subcortical routes can mediate implicit memory retrieval across the hemispheres. Two individuals with complete section of all forebrain commissures, L.B. and N.G., were given tests of recall and recognition (explicit memory) and stem-completion priming (implicit memory). The right and left hemispheres of N.G. and the left hemisphere of L.B. exhibited significant intrahemispheric priming. Interhemispheric priming was similar in extent to intrahemispheric priming. Under several intra- and interhemispheric conditions, significant implicit retrieval occurred in the face of abnormal explicit retrieval. Because all forebrain commissures had been severed in L.B. and N.G., interhemispheric priming was necessarily supported by subcortical structures. The observed dissociation between explicit and implicit memory performance indicates that the routes of interhemispheric transfer vary with type of memory retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory in amnesia: An analysis of data-driven and conceptually driven processes.

The extent to which data-driven and conceptually driven processing determines amnesic patients' differential performance on implicit and explicit tasks was investigated. In 2 data-driven tasks, words that looked visually similar to target words were used as cues for a graphemic production task (implicit) and a graphemic cued-recall task (explicit). In 2 conceptually driven tasks, words semantically related to the target words were used as cues for both a production task and a cued-recall task. The nature of the task instructions consistently determined amnesic patient performance, regardless of the nature of the processing required. Thus, the distinction between implicit and explicit tasks captured the performance of amnesic patients better than did the distinction between data-driven and conceptually driven processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spared priming despite impaired comprehension: Implicit memory in a case of word-meaning deafness.

Previous research has established that direct priming effects on implicit memory tests can be dissociated from explicit remembering. Evidence from studies of college students suggests that priming on various implicit tests can be characterized as a presemantic phenomenon: Priming can occur at full strength following nonsemantic encoding tasks that typically produce low levels of explicit memory. To provide a strong test of this idea, auditory priming in a case of word-meaning deafness was examined. Despite the patient's impaired auditory comprehension abilities, he showed normal priming on auditory identification tests after study-list exposure to spoken words. Results support the idea that priming depends on perceptual systems that operate at a presemantic level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory memory for timbre.

Psychophysical studies are reported examining how the context of recent auditory stimulation may modulate the processing of new sounds. The question posed is how recent tone stimulation may affect ongoing performance in a discrimination task. In the task, two complex sounds occurred in successive intervals. A single target component of one complex was decreased (Experiments 1 and 2) or increased (Experiments 3, 4, and 5) in intensity on half of trials: The task was simply to identify those trials. Prior to each trial, a pure tone inducer was introduced either at the same frequency as the target component or at the frequency of a different component of the complex. Consistent with a frequency-specific form of disruption, discrimination performance was impaired when the inducing tone matched the frequency of the following decrement or increment. A timbre memory model (TMM) is proposed incorporating channel-specific interference allied to inhibition of attending in the coding of sounds in the context of memory traces of recent sounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit components of prejudice.

Research on implicit and explicit prejudice has treated implicit prejudices as a unitary construct characterized by automatic access to negative concepts. The present article makes the case that tasks purported to measure implicit prejudice actually assess 2 different processes. Some assess the extent to which prejudice is activated automatically on the perception of a member of the target group. Other implicit tasks assess the extent to which prejudice is automatically applied in judgment. In the reported study, participants completed 4 implicit and 2 explicit measures of prejudice against women. Factor analysis yielded a 3-factor solution. The solution provides support for the distinction between explicit prejudice and 2 types of implicit prejudice corresponding to automatic activation and automatic application of prejudice. Prejudice appears to be a multifaceted construct, different aspects of which are measured by different tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit and explicit memory in amnesia: some explanations and predictions by the TraceLink model

After a brief overview of some of the characteristics and neuroanatomy of amnesia, a new model of amnesia is described: the TraceLink model. One novel aspect of the model is that it makes specific and testable predictions regarding semantic dementia, a recently described disorder that is viewed here as being related to amnesia. The TraceLink model consists of: a trace system (roughly the neocortix), a link system (hippocampus and adjacent areas), and a modulatory system (certain basal forebrain nuclei). Different forms of learning in the TraceLink model are explained, followed by a discussion of implicit and explicit memory, prominence (ease of recall) and persistence (resistance to brain damage), consolidation, and Ribot gradients in retrograde amnesia. Patterns of recovery from retrograde amnesia are also discussed, and novel predictions are derived regarding implicit memory and various forms of amnesia.     

Affective valence of words, explicit and implicit memory in clinical depression

Explicit and implicit memory for affectively valenced words (positive, negative or neutral) were investigated in 30 patients suffering from a major depressive episode (DSM-III-R criteria) and 30 normal control subjects. Explicit memory was assessed with a free-recall and a recognition task and implicit memory with a word-stem completion task. Depressed and control subjects recalled more emotional, i.e., positive and negative, words than neutral ones. They recognized less negative than neutral words. In contrast, to recall and recognition performance, word-completion performance was not sensitive to the affective valence of words: depressed and control subjects exhibited equivalent priming of positive, negative and neutral words. These results indicate that, in depressed and normal subjects, the affective valence of words influences memory when conscious, intentional recollection is required but is devoid of effect when such a recollection is not required.     

Implicit and explicit prejudice and interracial interaction.

The present research examined how implicit racial associations and explicit racial attitudes of Whites relate to behaviors and impressions in interracial interactions. Specifically, the authors examined how response latency and self-report measures predicted bias and perceptions of bias in verbal and nonverbal behavior exhibited by Whites while they interacted with a Black partner. As predicted, Whites' self-reported racial attitudes significantly predicted bias in their verbal behavior to Black relative to White confederates. Furthermore, these explicit attitudes predicted how much friendlier Whites felt that they behaved toward White than Black partners. In contrast, the response latency measure significantly predicted Whites' nonverbal friendliness and the extent to which the confederates and observers perceived bias in the participants' friendliness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)