Reward influences the allocation but not the availability of resources in visual working memory

Visual working memory possesses strict capacity constraints which place limits on the availability of resources for encoding and maintaining information. Studies have shown that prospective rewards improve performance on visual working memory tasks, but it remains unclear whether rewards increase total resource availability or rather influence the allocation of resources without affecting availability. Participants performed a continuous report visual working memory task with oriented grating stimuli. On each trial, participants were presented with a priority cue, which signaled the item most likely to be probed, and a reward cue, which signaled the magnitude of a performance-contingent reward. We showed that rewards decreased recall error for cued items and increased recall error for non-cued items. We further demonstrated that rewards produced a tradeoff in the probability of successfully encoding a cued versus a non-cued item rather than a tradeoff in recall precision or the probability of binding errors. Lastly, we showed that rewards only affected resource allocation when participants were given the opportunity to engage proactive control prior to encoding. These findings indicate that rewards influence the flexible allocation of resources during selection and encoding in visual working memory, but do not augment total capacity.

Using Interviews to Understand Why: Challenges and Strategies in the Study of Motivated Action

This article examines an important and thorny problem in interview research: How to assess whether what people say motivated their actions actually did so? We ask three questions: What specific challenges are at play? How have researchers addressed them? And how should those strategies be evaluated? We argue that such research faces at least five challenges— deception, recall error, reasonableness bias, intentionality bias, and single-motive bias—that more than a dozen strategies have been deployed to address them; that the strategies have been external, internal, or interactional in nature; and that each class of strategies demands distinct evaluation criteria. Researchers will likely fail to uncover motivation if they ignore the possibility of each challenge, conflate one challenge with another, or deploy strategies unmatched to the challenge at hand. Our work helps systematize the evaluation of interview-based studies of motivated action and strengthen the scientific foundations of in-depth interview research.

Strategy guides feature recall of a single object in working memory task

Over past couple of decades our understanding of visual working memory (VWM), and working memory in general, has been predominantly in line with the capacity debate. We recently opened a new line of inquiry regarding the recall of a single object to go beyond the capacity debate, and showed that a series of feature probe questions about a single object yields poorer recall later in the sequence (Sengupta et al, 2020). In the current work we focused on another aspect of sequential feature recall - mainly regarding whether recall can be improved by asking the same question twice. To that end, we chose to focus on two features - color and location, and we contrasted repeat and non-repeat (from the standpoint of feature questions) trials in a series of two experiments. In repeat trials either color or location would be probed twice consecutively. In non-repeat trials color and location probes were presented one after the other in random order. In all trials the stimulus was a small colored oriented line presented for 1 sec in a location within 4o of visual angle. The recall of color and location were mapped onto continuous variable like Sengupta et al, 2020 - for instance, color recall was mapped onto a color wheel. In the first experiment, we used an unaltered color wheel when the color question was repeated. For the second experiment, we used a rotated color wheels for two consecutive color recall trials. We observed an increase in recall error for both repeat and non-repeat condition for location when the probe was at the second question in both experiments. However, color recall error did not increase for second repeat question condition in Experiment 1 as opposed to the non-repeat condition. On the other hand, in Experiment 2 we observed the expected increase in recall error for both repeat and non repeat condition for color probe at the second question. This maybe due to the fact that participants used an ‘anchoring’ strategy in Experiment 1 by remembering where they clicked on the color wheel in the first question. The rotation of color wheel in second experiment destroys the anchor leading to the aforementioned result. The results show that trying to recall the same feature again leads to degradation of recall accuracy for both color and location, and human beings may use different strategies for recall in working memory tasks.

A Mechanism for Sketch Based Image Retrievals using Generalized Gamma Mixture Model (GGMM) and Relevance Feedback Mechanism

The exponential growth of multimedia technologies facilitated the ease of developing various images having different shapes and scales. With the advent of mobile technologies, these messages so generated are being transmitted across the globe in different formats for different purposes. With these advancements methodologies thus developed for identifying or expressing subjects (individuals) their views by means of sketches. These sketch based images have many advantages, in particular, these images can be well considered in situations where the narration and capturing becomes difficult. The present article underlines a mechanism to interpret the images and also addresses the retrieval of such sketch based images using Generalized Gamma Mixture Model. The relevance feedback mechanism is utilized to retrieve more relevant to sketch based images based on the query image. The efficiency of the proposed word is evaluated using metrics like precision, recall, error rate, and retrieval accuracy.

Age differences in the precision of memory at short and long delays

Age differences are well established for many memory tasks assessing both short-term and long-term memory. However, how age differences in performance vary with increasing delay between study and test is less clear. Here we report two experiments in which participants studied a continuous sequence of object-location pairings. Test events were intermixed such that participants were asked to recall the precise location of an object following a variable delay. Older adults exhibit a greater degree of error (distance between studied and recalled locations) relative to younger adults at short (0-2 intervening events) and longer delays (10-25 intervening events). Mixture modeling of the distribution of recall error suggests that older adults do not fail to recall information at a significantly higher rate than younger adults. Instead, what they do recall appears to be less precise. Follow up analyses demonstrate that this age difference emerges following only one or two intervening events between study and test. These findings are consistent with the suggestion that aging does not greatly impair recall from the focus of attention but age differences emerge once information is displaced from this highly accessible state. Further, we suggest that age differences in the precision of memory, but not the probability of successful recall, may be due to the use of more gist-like representations in this task.

The Correlation between Menstrual Symptoms and College Academic Activities [University of West Florida]

Sleep and the menstrual cycle are greatly intertwined, Both sleep and menstruation can affect each other: sleep quality can be related to the regularity and symptoms of the menstrual cycle. Women have poorer sleep quality during menstruation, including difficulties in falling asleep and maintaining sleep. Few studies have looked directly at the correlation between menstrual symptoms, sleep quality, stress, and college academic activities. The purpose of this study is to determine whether there is a correlation between female students’ menstrual cycle symptoms, stress levels, sleep quality, and academic activities. We are also investigating whether the students compensate for the negative effects of menstruation, how they compensate, and how much they compensate. For example, “Do you compensate for sub-optimal conditions caused by your menstrual symptoms and their severity? If yes, how so?” A preliminary survey will be given to qualify participants for the longitudinal study. Data for this longitudinal study will be gathered through a daily self-reported survey with semi-structured Likert-scale and open-ended questions, about severity of menstrual symptoms; sleep quality, study habits, stress levels, and academic activities both during and not during menstruation. In order to avoid recall error and ensure consistency, we will conduct a naturalistic observational and longitudinal study wherein participants will answer questions nightly over the course of two months. A regression statistical analysis will be conducted. To compare performance and academic habits, participants will be separated into three academic groups according to GPA: 2.5-2.9, 3.0-3.4, and 3.5+. We expect to find that, during menstruation, relative to non-menstruation, participants experience higher stress levels, poorer sleep quality, a difference in academic activities, and compensation for deficiencies, with students with higher GPAs having higher rates of compensation. Data collection will be conducted in March and data analysis will be completed by April 2019.