Short-term memory for flavour

The short-term memory for the flavour of a wine in frequent but nonexpert drinkers was studied in an experiment comparing memory for wine under conditions where participants imagined and remembered a target wine with memory under conditions where participants carried out subsequent imaging and image rating tasks on the wine and on competing mental images. The results show that the cognitive operation of mental image rating produced enhanced memory when the operations were performed on the image of the target wine and somewhat impaired memory when operations were performed on an image of a competing flavour or operations performed on mental images in other domains. It is concluded that sensory traces of flavour may be effectively maintained in short-term memory when supported by appropriate encoding operations.     

Subitizing and counting processes in young children

Children attending the first grade in school were instructed to tell the number of dots (1–9) presented on a screen. The response latencies were related to the number of dots by two different linear relations for each subject. The first of these had a slope of about 0.1 sec/dot, was applicable for the encoding of 1–3 dots, and was taken as an indication of a subitizing process. The second linear relation was applicable for 5–9 dots and had a slope of about 1.0 sec/dot reflecting the speed of a counting process. The average intersection between the functions was located at 3.22 dots. The results were compared with earlier investigations of adult subjects who on the average subitize 6 dots and count 1 dot in about 0.4 sec. It was subitizing process being higher for adults. If the encoding of a stimulus has not been terminated within about 1.5 sec for children and adults the stimulus has instead to be identified in either a counting or an estimating process.     

Short-term memory in autism spectrum disorder

Three experiments examined verbal short-term memory in comparison and autism spectrum disorder (ASD) participants. Experiment 1 involved forward and backward digit recall. Experiment 2 used a standard immediate serial recall task where, contrary to the digit-span task, items (words) were not repeated from list to list. Hence, this task called more heavily on item memory. Experiment 3 tested short-term order memory with an order recognition test: Each word list was repeated with or without the position of 2 adjacent items swapped. The ASD group showed poorer performance in all 3 experiments. Experiments 1 and 2 showed that group differences were due to memory for the order of the items, not to memory for the items themselves. Confirming these findings, the results of Experiment 3 showed that the ASD group had more difficulty detecting a change in the temporal sequence of the items.     

Short-term flavour memory in the rat

In a series of experiments, rats were exposed twice to a flavour at times T1 and T2, and the second of these exposures was followed by toxicosis. The level of the subsequent aversion was viewed as an index of whether the flavour had been recognised as familiar at T2, with a familiar flavour accruing less aversiveness than an unfamiliar one. A flavour was recognised as familiar at time T2 after a long flavour-exposure at time T1 (Experiment Ia) when moderate (3·5 h) and long (27·5 h) T1-T2 intervals were employed but was so recognised after a brief exposure at T1 (Experiment Ib) only when a moderate T1-T2 interval was employed. The memorial processes underlying flavour recognition after a brief flavour exposure were assumed, therefore, to be transient. The remaining experiments employed a brief flavour exposure at T1 and moderate T1-T2 intervals in various attempts to disrupt flavour recognition. Recognition at T2, however, was not disrupted when one (Experiment II), or three (Experiment IV) distractor flavours were interpolated between the target flavour's presentations at T1 and T2. This failure was not due to the distractor having proactively interfered with the associability of the target flavour with illness at T2 (Experiment III). Further, recognition was not disrupted when the position of the target flavour's presentation at T1 was varied across a list of distractor flavours (Experiment V), nor when the similarity of the distractor and the target flavour was varied (Experiment VI). The results indicate that the processes subserving recognition after a brief presentation of that flavour, although transient, are resistant to interference and were discussed in terms of current theories of short-term memory in animals.     

Short-term memory function in young readers

Twelve good readers and 12 poor readers, 10-y4-olds, were given memory span tests, and memory scanning tests, in both auditory and visual modalities. Their concept of a letter pattern was also tested. The major finding was that short-term memory (STM) function deteriorated over time in the poor reading group. When modality was switched the good readers showed a release from proactive inhibition (PI); the poor readers did not. Among good readers, memory scanning in the auditory modality occurred at about the same speed as memory scanning in the visual modality; among the poor readers, auditory speed gradually lagged relative to visual rates. Poor readers were more likely (than good readers) to lack the concept of a letter pattern. Stepwise regressions showed that different patterns of variables were assocated with different types of reading errors. Implicatios for model construction were discussed.     

Training counting skills and working memory in preschool

Previous studies have shown that early numeracy skills predict later mathematics learning and that they can be improved by training. Cognitive abilities, especially working memory (WM), play an important role in early numeracy, as well. Several studies have shown that working memory is related to early numeracy. So far, existing literature offers a good few examples of studies in which WM training has led to improvements in early numerical performance as well. In this study, we aim at investigating the effects of two different training conditions: (1) counting training; and (2) simultaneous training of WM and counting on five‐ to six‐year‐old preschoolers' (N = 61) counting skills. The results show that domain‐specific training in mathematical skills is more effective in improving early numerical performance than WM and counting training combined. Based on our results, preschool‐aged children do not seem to benefit from short period group training of WM skills. However, because of several intervening factors, one should not conclude that young children's WM training is ineffectual. Instead, future studies should be conducted to further investigate the issue.     

Short-term memory for intonation.

Ss were presented with lists of 16 words, each word spoken in one of four intonations. The final word was a repetition of one of the first 15 words, 40 Ss having to judge whether it was spoken in the same intonation as its earlier occurrence. A control group of 40 Ss did a similar task, ignoring intonation. Retention of intonation was significantly poorer, indicating that intonation is an additional load not normally retained. This argues against acoustic or articulatory encoding in short-term memory and in favor of an abstract-verbal encoding mode. Results are also interpreted as supporting the position that verbal and motor short-term membory obey similar laws.     

Short-term memory across eye blinks

The effect of eye blinks on short-term memory was examined in two experiments. On each trial, participants viewed an initial display of coloured, oriented lines, then after a retention interval they viewed a test display that was either identical or different by one feature. Participants kept their eyes open throughout the retention interval on some blocks of trials, whereas on others they made a single eye blink. Accuracy was measured as a function of the number of items in the display to determine the capacity of short-term memory on blink and no-blink trials. In separate blocks of trials participants were instructed to remember colour only, orientation only, or both colour and orientation. Eye blinks reduced short-term memory capacity by approximately 0.6–0.8 items for both feature and conjunction stimuli. A third, control, experiment showed that a button press during the retention interval had no effect on short-term memory capacity, indicating that the effect of an eye blink was not due to general motoric dual-task interference. Eye blinks might instead reduce short-term memory capacity by interfering with attention-based rehearsal processes.     

Short-term memory and aphasia.

Short-term retention tests of verbal item information (short-term memory for items) and order information (memory for sequences) were administered to aphasic, nonaphasic brain-damaged, and normal subjects. Memory for both parameters was significantly impaired in aphasics only. One-third of errors made by aphasics resulted from a specific, separable defect in short-term memory for sequences. As information load increased, memory for sequences became critical for linguistic performance of aphasics.     

Short-term memory for time intervals

The effect of intertrial interval, preset interval, and retention interval on the performance of rats in a time estimation task was described. On each trial a signal was presented for a duration of 2 to 8 sec. Eighteen rats were trained to press one lever (the short response) if the signal was shorter than 4 sec, and another lever (the long response) if the signal was longer than 4 sec. When trials were massed (Experiment 1), the percentage long response was affected by the classification of the previous signal, but not by its actual duration. This suggests that the animals remembered the response made on the previous trial, but not the signal duration. If a response was not permitted on the previous trial (Experiment 2), the duration or classification of the previous signal had no effect on performance. This supports the conclusion from the first experiment and suggests that an animal can reset its internal clock in less than 2 sec. In Experiment 3, the difference limen of the psychophysical function increased with the duration of the retention interval, but the point of subjective equality did not change. This suggests that resetting of the internal clock occurs on a non-time dimension.     

Short-term recognition memory of tones

Four Os participated in a recognition memory experiment for a period of 5 weeks. The task required O to judge whether two temporally sequenced tones (ISI = 0.5, 2.0, or 8.0 sec) were the “same” or “different ” Latencies and confidence ratings were obtained for each judgment. TSD analyses applied to individual O’s data indicated consistent and rapidly decreasing d’s as a function of ISI. ROC functions generated from the latencies and ratings produced comparable results, indicating the feasibility of using latency measures along with the type of judgments made to obtain sensitivity measures. Response bias, as indicated by the differences in the latencies between “same” and “different” judgments, did not produce consistent trends.