Incidental Memory Performance Research Articles

Recall of Odorous Objects in Virtual Reality

The aim was to investigate how the congruence of odors and visual objects in virtual reality (VR) affects later memory recall of the objects. Participants (N = 30) interacted with 12 objects in VR. The interaction was varied by odor congruency (i.e., the odor matched the object’s visual appearance, the odor did not match the object’s visual appearance, or the object had no odor); odor quality (i.e., an authentic or a synthetic odor); and interaction type (i.e., participants could look and manipulate or could only look at objects). After interacting with the 12 objects, incidental memory performance was measured with a free recall task. In addition, the participants rated the pleasantness and arousal of the interaction with each object. The results showed that the participants remembered significantly more objects with congruent odors than objects with incongruent odors or odorless objects. Furthermore, interaction with congruent objects was rated significantly more pleasant and relaxed than interaction with incongruent objects. Odor quality and interaction type did not have significant effects on recall or emotional ratings. These results can be utilized in the development of multisensory VR applications.

The Relation between Sustained Attention and Incidental and Intentional Object-Location Memory.

The role of attention allocation in object-location memory has been widely studied through incidental and intentional encoding conditions. However, the relation between sustained attention and memory encoding processes has scarcely been studied. The present study aimed to investigate performance differences across incidental and intentional encoding conditions using a divided attention paradigm. Furthermore, the study aimed to examine the relation between sustained attention and incidental and intentional object-location memory performance. Based on previous findings, an all women sample was recruited in order to best illuminate the potential effects of interest. Forty-nine women participated in the study and completed the psychomotor vigilance test, as well as object-location memory tests, under both incidental and intentional encoding divided attention conditions. Performance was higher in the incidental encoding condition than in the intentional encoding condition. Furthermore, sustained attention correlated with incidental, but not with intentional memory performance. These findings are discussed in light of the automaticity hypothesis, specifically as it regards the role of attention allocation in encoding object-location memory. Furthermore, the role of sustained attention in incidental memory performance is discussed in light of previous animal and human studies that have examined the brain regions involved in these cognitive processes. We conclude that under conditions of increased mental demand, executive attention is associated with incidental, but not with intentional encoding, thus identifying the exact conditions under which executive attention influence memory performance.

Exploring the Profile of Incidental Memory in Patients with Amnestic Mild Cognitive Impairment and Mild Alzheimer’s Disease

Incidental memory can be defined as the ability to acquire information unintentionally. The present study investigated incidental memory performance in amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD) patients; additionally, hippocampal atrophy between groupswas examined. Twenty-nine aMCI patients (14 with hippocampal atrophy, measured by the Medial Temporal Lobe Atrophy scale), 15 mild AD patients, and 20 cognitively intact individuals underwent a detailed medical and neuropsychological assessment examining intentional memory, using the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test. Participants first took part in a driving simulator experiment, followed by an unexpected incidental memory questionnaire referring to elements related to the driving simulation. The mild AD group performed worse than the aMCI group and the control group both in incidental and intentional memory tasks, whereas the aMCI group differed significantly from the control group only in the intentional memory tasks. The incidental recognition memory task was the only measure that differed between aMCI patients with and without hippocampal atrophy. Moreover, incidental memory tasks were the only measures that correlated significantly with both left and right hippocampal atrophy. The current findings indicate that incidental memory testing may provide potentially useful information for detecting aMCI patients with greater hippocampal atrophy, who may be considered at higher risk of developing dementia due to AD.

Emotional words impact the mind but not the body: Evidence from pupillary responses

Pupillary responses have been shown to be sensitive to both task load and emotional content. We investigated the interplay of these factors in the processing of single words that varied in emotional valence and arousal. Two tasks of different cognitive load, uninstructed reading and a lexical decision task, were employed, followed by an unannounced recognition task. Reaction times were faster and incidental memory performance was better for high-arousing than for low-arousing words. In contrast to previous findings for pictures and sounds, high-arousing words elicited smaller pupillary responses than low-arousing words; these effects were independent of task load, which increased pupil diameter. Therefore, emotional arousal attributed to words does not mandatorily activate the autonomic nervous system, but rather works on a cognitive level, facilitating word processing.

Benzodiazepine Use Associated with Decreased Memory for Psychoeducation Material in Cognitive Behavioral Therapy for Panic Disorder

In laboratory studies with nonanxious participants, benzodiazepines (BZ) reliably induce anterograde amnesia. It remains unclear whether memory impairments exist for information presented in therapy among anxiety patients who are concomitantly taking BZs. This naturalistic study compared 16 panic disorder patients who were daily BZ users with 16 age- and education-matched, nonmedicated panic disorder patients. An incidental memory task assessed memory for psychoeducation material on the origins and management of somatic anxiety symptoms presented during group cognitive behavioral therapy (CBT). BZ users showed significantly poorer memory performance than controls although there were no group differences in anxiety symptoms, rates of psychiatric comorbidity, or sedation. Among BZ users, a higher number of minutes away from post peak drug-blood concentration when encoding began, was also associated with better incidental memory performance. Although causation cannot be inferred from this naturalistic study, the memory impairments observed among BZ users may contribute to the poorer efficacy of CBT previously documented in panic disorder patients receiving adjunctive BZs.

Levels of word processing and incidental memory: dissociable mechanisms in the temporal lobe.

Word recall is facilitated when deep (e.g. semantic) processing is applied during encoding. This fact raises the question of the existence of specific brain mechanisms supporting different levels of information processing that can modulate incidental memory performance. In this study we obtained spatiotemporal brain activation profiles, using magnetic source imaging, from 10 adult volunteers as they performed a shallow (phonological) processing task and a deep (semantic) processing task. When phonological analysis of the word stimuli into their constituent phonemes was required, activation was largely restricted to the posterior portion of the left superior temporal gyrus (area 22). Conversely, when access to lexical/semantic representations was required, activation was found predominantly in the left middle temporal gyrus and medial temporal cortex. The differential engagement of each mechanism during word encoding was associated with dramatic changes in subsequent incidental memory performance.

Measures of fluency as predictors of incidental memory among older adults.

This study investigated fluency performance as a mediator of age-related declines in incidental memory performance as both are thought to rely on strategic retrieval processes. A large sample of community dwelling older adults completed a battery of tests assessing fluency, verbal knowledge, speed of information processing, and incidental recall. Fluency measures included initial and excluded letter fluency and the Uses for Objects Test, and they were assumed to reflect increasing reliance on strategic retrieval search. Speed emerged as the best mediator of age-related variance in incidental recall, and Uses for Objects Test performance added to the variance after controlling for verbal knowledge and speed. The results suggest that age-related decline in incidental recall is largely due to speed and the strategic search of memory.

Remembering pictures: Pleasure and arousal in memory.

Incidental memory performance for pictures that varied along the affective dimensions of pleasantness and arousal was assessed. For both an immediate and delayed (1 year later) free-recall task, only the arousal dimension had a stable effect on memory performance: Pictures rated as highly arousing were remembered better than low-arousal stimuli. This effect was corroborated in a speeded recognition test, in which high-arousal materials encoded earlier in the experiment produced faster reaction times than their low-arousal counterparts. Pleasantness affected reaction time decisions only for pictures not encoded earlier. These results suggest that whereas both the dimensions of pleasantness and arousal are processed at initial encoding, long-term memory performance is mainly affected by arousal.

The Effects of Amount of Processing on Recall and Recognition

Johnson-Laird, Gibbs and de Mowbray (1978) and Ross (1981) have argued that amount of processing, as indexed by the overall number of decisions a subject makes, provides a good predictor of incidental memory performance. Conversely, McClelland, Rawles and Sinclair (1981) have provided evidence that it is normally the number of positive decisions rather than the overall number of decisions per se that determines level of recall. The present study replicated and extended the findings of McClelland and his colleagues. In free recall (Experiment 1 and 3), cued recall (Experiment 3) and recognition in the presence or absence of context cues (Experiments 2 and 3), an account based on number of positive decisions provided by far the better explanation. Experiment 3 also revealed that the experimental manipulations had a somewhat greater effect on recall than recognition. This is explained in terms of Tulving and Pearlstone's (1966) distinction between availability and accessibility. It is suggested that words associated with negative decisions are not only less accessible in memory, there are also fewer of them available for recall and recognition.

Encoding activities and free recall of categorized and noncategorized pictures by young children

Free recall of categorized and noncategorized lists of pictures by children in kindergarten and second grade was studied under incidental memory conditions involving a semantic orient­ ing task (i.e.• niceness judgments) or a physical orienting task (i.e., color judgments) in com­ parison with an intentional memory condition. The recall scores in the intentional and the incidental/semantic conditions were equivalent and were significantly greater than those in the incidental/physical condition for children at both ages and for both categorized and noncategor­ ized lists. This paper describes an exploratory study of the notion of an interaction between the extent ofknowledge ­ base development and the effects ofdifferent orienting tasks (e.g., see lindberg, 1980). Certainly, if there are no semantic structures, then an orienting task designed to tap this type of structure should be no more effective than a task orienting the child to more physical attri­ butes of the material. However, as increasing amounts of semantic structure are added to the knowledge-base, processing that taps this structure should become in­ creasingly effective . On the other hand , semantic struc­ ture that is not accessed by a particular orienting task should play no role in mediating incidental recall (see Brown, Bransford , Ferrara, & Campione , 1983, and Eysenck , 1982, for reviews). In short, good incidental memory performance (at any age) would seem to require both mnemonically useful knowledge and an orienting task that taps that knowledge. This reasoning leads to several expectations about the development of incidental memory performance that are as yet untested. For example, a semantic orienting task would be expected to lead to greater recall than a physical orienting task at an earlier age with a cate­ gorized list than with a noncategorized list. This follows from other evidence that the usefulness of the organiza­ tional structure in a categorized list emerges earlier than that in a noncategorized list (e.g., see Ornstein , Naus,

Processing domain, encoding elaboration, and memory trace strength

Trace strength was examined as a function of single and spaced-multiple encodings within and across the orthographic, acoustic, and semantic domains. Incidental memory performance (recall and recognition) replicated effects obtained by Craik and Tulving (1975) and was used to predict performance in multiple encoding conditions. The recall results revealed that multiple encodings yielded additive or greater than additive retention effects while the recognition accuracy results revealed additive or less than additive effects. In addition, recognition latency was systematically related to initial processing conditions and accuracy. The accuracy data suggest that processing domains are qualitatively different and independent. The recognition latency data suggest a model which assumes parallel processing and pattern matching within each of these domains.