Comparison of accuracy in auditory and tactile recognition memory for environmental stimuli.

Accuracy rates for auditory and tactile recognition of naturalistic stimuli over a 7-day period are compared. 40 subjects listened to 50, 107, or 194 naturalistic sounds and were tested immediately or after delays of 2 or 7 days. 30 other subjects handled but did not visually inspect 150 common objects and were tested over the same three delay intervals. Recognition accuracy for sounds was 87.5%, 82.5%, and 80.4% while common objects were recognized at 96.0%, 93.8%, and 88.5% rates of accuracy. Tactile recognition memory was superior to auditory recognition memory. The recognition accuracies of both modalities were affected by the delay interval. The number of items inspected had no effect on the recognition memory for sounds. Following a delay of 1 wk., the accuracy of recognition relative to the original level of function was 92% for both modalities.     

Report on blind subjects' tactile and auditory recognition for environmental stimuli.

In two related experiments on recognition-on touch and audition-accuracy rates were obtained from congenitally blind subjects and compared with those for normally sighted subjects. In Exp. 1, 5 blind subjects inspected, i.e., handled, 150 common objects and were tested after a delay of 7 days. In Exp. 2, 9 blind subjects listened to 194 naturalistic sounds and were also tested after a 7-day delay. Accuracy of tactile recognition for the blind was 89.4% while it was 87.9% for the normally sighted. Sound recognition by blind subjects was 76.6% and for the normally sighted it was 78.4%. Neither difference was statistically significant.     

Facilitation and impairment of event memory produced by photograph review

Selectively reviewing some items from a larger set of previously learned items increases memory for the items that are reviewed but may also be accompanied by a cost: Memory for the nonreviewed items may be impaired relative to cases where no review occurs at all. This cost to nonreviewed items has primarily been shown in contexts of verbal list learning and in situations where the reviewed and nonreviewed items are categorically or semantically related. Using a more naturalistic impetus to selective review--photographs relating to previously experienced events--we assessed whether the memory of older and younger adults for unrelated complex activities that they themselves had performed was also impaired due to nonreview. Both younger and older adults showed impaired memory for nonreviewed activities when tested with free recall (Experiment 1), but not when tested with recognition or cued recall (Experiment 2). If mitigating retrieval cues are unavailable, selective review may impair memory for nonreviewed everyday events.     

Verbal mediation and memory for novel figural designs: a dual interference study

To the extent that all types of visual stimuli can be verbalized to some degree, verbal mediation is intrinsic in so-called "visual" memory processing. This impurity complicates the interpretation of visual memory performance, particularly in certain neurologically impaired populations (e.g., aphasia). The purpose of this study was to investigate the relative contributions of verbal mediation to recognition memory for visual stimuli that vary with respect to their amenability to being verbalized. In Experiment 1, subjects attempted to verbally describe novel figural designs during presentation and then identify them in a subsequent recognition memory test. Verbalizing these designs facilitated memory. Stimuli that were found to be easiest or most difficult to verbalize at the group level were retained for the second study. In Experiment 2, subjects evidenced superior recognition memory for the relatively easy to verbalize items. This advantage was attenuated in subjects who performed a concurrent verbal interference task during encoding, but not in those who performed an analogous visual interference task. These findings provide evidence that impoverished verbal mediation disproportionately impedes memory for visual material that is relatively easy to verbalize. Implications for the clinical assessment of visual memory are discussed.     

The effects of retention intervals on self- and proxy reports of purchases

Two studies explored underlying differences between self- and proxy reports and determining whether proxy reporters process and retrieve information the same way self-reporters do. In both studies, participants recorded their own and a target person's incidental purchases for two weeks and then returned, either immediately or one-week after the diary-keeping period, for two recall tests. These tests pertained to self-and proxy purchases. The reported items were scored against the recorded ones. In Study 1, the data indicate that proxies tend to recall more typical events than do self-reporters immediately following the diary-keeping period. However, after a delay of one week, both proxy and self-reporters tended to report typical items. These findings suggest that, at least initially, self- and proxy reporters process the information differently but that after one week they process it similarly. Study 2 employed a method that was identical to that of Study 1 except that participants were given a recognition test. The verbal protocols from the recognition test indicate that participants used different strategies to determine who made the purchase. Whereas participants focused on perceptual details surrounding the event when identifying their own purchases, proxies engaged in various strategies to identify their spouses' purchases.     

Remembering environmental sounds: The role of verbalization at input

Two experiments investigated the role of verbalization in memory for environmental sounds. Experiment i extended earlier research (Bower & Holyoak, 1973) showing that sound recognition is highly dependent upon consistent verbal interpretation at input and test. While such a finding implies an important role for verbalization, Experiment 2 suggested that verbalization is not the only efficacious strategy for encoding environmental sounds. Recognition after presentation of sounds was shown to differ qualitatively from recognition after presentation of sounds accompanied with interpretative verbal labels and from recognition after presentation of verbal labels alone. The results also suggest that encoding physical information about sounds is of greater importance for sound recognition than for verbal free recall, and that verbalization is of greater importance for free recall than for recognition. Several alternative frameworks for the results are presented, and separate retrieval and discrimination processes in recognition are proposed.     

The effects of retention intervals on self- and proxy reports of purchases

Two studies explored underlying differences between self- and proxy reports and determining whether proxy reporters process and retrieve information the same way self-reporters do. In both studies, participants recorded their own and a target person's incidental purchases for two weeks and then returned, either immediately or one-week after the diary-keeping period, for two recall tests. These tests pertained to self- and proxy purchases. The reported items were scored against the recorded ones. In Study 1, the data indicate that proxies tend to recall more typical events than do self-reporters immediately following the diary-keeping period. However, after a delay of one week, both proxy and self-reporters tended to report typical items. These findings suggest that, at least initially, self- and proxy reporters process the information differently but that after one week they process it similarly. Study 2 employed a method that was identical to that of Study 1 except that participants were given a recognition test. The verbal protocols from the recognition test indicate that participants used different strategies to determine who made the purchase. Whereas participants focused on perceptual details surrounding the event when identifying their own purchases, proxies engaged in various strategies to identify their spouses' purchases.     

When acoustic sequences are not perceptual sequences: The global perception of auditory patterns

Warren, Bashford, and Gardner (1990) found that when sequences consisting of 10 40-msec steady-state vowels were presented in recycled format, minimal changes in order (interchanging the position of two adjacent phonemes) produced easily recognizable differences in verbal organization, even though the vowel durations were well below the threshold for identification of order. The present study was designed to determine if this ability to discriminate between different arrangements of components is limited to speech sounds subject to verbal organization, or if it reflects a more general auditory ability. In the first experiment. 10 40-msec sinusoidal tones were substituted for the vowels; it was found that the easy discrimination of minimal changea in order is not limited to speech sounds. A second experiment substituted 10 40-msec frozen noise segments for the vowels. The succession of noise segments formed a 400-msec frozen noise pattern that cannot be considered as a sequence of individual sounds, as can the succession of vowels or tones. Nevertheless, listeners again could discriminate between patterns differing.only in the order of two adjacent 40-msec segments. These results, together with other evidence, indicate that it is not necessary foracoustic sequences of brief items (such as phonemes and tones) to be processed asperceptual sequences (that is, as a succession of discrete identifiable sounds) for different arrangements to be discriminated. Instead, component acoustic elements form distinctive “temporal compounds,” which permit listeners to distinguish between different arrangements of portions of an acoustic pattern without the need for segmentation into an ordered series of component items. Implications for models dealing with the recognition of speech and music are discussed.     

Is time-based prospective remembering mediated by self-initiated rehearsals? Role of incidental cues, ongoing activity, age, and motivation

The present research examined self-reported rehearsal processes in naturalistic time-based prospective memory tasks (Study 1 and 2) and compared them with the processes in event-based tasks (Study 3). Participants had to remember to phone the experimenter either at a prearranged time (a time-based task) or after receiving a certain text message (an event-based task) and record the details of occasions when they thought about this intention during a 7-day delay interval. The rehearsal and retrieval of time-based tasks was mediated by more automatic than deliberate self-initiated processes. Moreover, the number of reported rehearsals without any apparent triggers was reliably higher in time- than in event-based tasks. Additional findings concern the effects of age, motivation, and ongoing activities on rehearsal and prospective memory performance.