Tag: Dasa Zeithamova

Spatial Location and Memory Integration

Presenter: Dahlia Mohd Razif – Business Administration, Human Physiology, Neuroscience, Psychology

Faculty Mentor(s): Lea Frank, Dasa Zeithamova

Session: (In-Person) Poster Presentation

Memory is flexible and can be influenced by other items or events that we have encountered. Memory integration refers to the concept that related memories are stored in the brain as overlapping representations which form a memory link that allow us to make new inferences or extract related information. Studies have shown that memory integration is enhanced by time proximity when items or events occur within a close time frame but not much is known regarding how spatial positioning affects memory integration. 160 participants will be split into a spatial overlapping condition and a no spatial overlapping condition. This experiment consists of a study trial, an associative inference test and an associative memory test. During the study trial, participants will be presented with object images positioned relative to base object images. For the associative inference test and memory test, object images will be presented as cues to evaluate the extent that participants can integrate the associations that share the common element of the base object as well as remember presented pairs during the study trial. As the date of submission of this abstract is prior to data collection, conclusions have not been realized. We hypothesize that spatial overlapping of items will result in diminished memory integration due to interference. This research can help deepen our understanding of how the brain encodes separate items and creates an integrated representation of the shared information.

Aging Effects on Perceptual and Conceptual Memory: Transformations from Short-term to Long-term Memory

Presenter: Anisha Adke

Faculty Mentor: Dasa Zeithamova-Demircan

Presentation Type: Poster 43

Primary Research Area: Science

Major: Biology

Funding Source: UROP Mini-Grant, University of Oregon, $1,000

Conceptual and precision memory are two functions of healthy and adaptive memory. Conceptual memory retains the gist of events. Precision memory allows memory of specific perceptual details of events, contrasting them from other similar experiences. Precision and conceptual memory may be differentially important for short-term memory and long-term memory. Long-term memories may have a tendency to retain meaning but lose details. This is adaptive in daily life, but may be a problem in certain situations, like during eyewitness testimonies, where details rather than generalities are essential. Loss of memory precision also characterizes normal aging, but it is unclear whether this occurs because details are lost in long-term memory or they are not encoded in short-term memory. The purpose of the study was to determine if memories transform from perceptual to conceptual over time and identify the effect of aging on this relationship.

Subjects’ memory were tested for general meaning (conceptual memory) or specific details (perceptual memory) either immediately (short-term) or after thirty minutes (long-term). Preliminary results show that short-term memory supports quicker and more accurate judgments of perceptual details, whereas long-term memory supports quicker and more accurate judgments of meaning. Future testing will assess whether older adults are quicker and more accurate in judgments of meaning in both long and short-term memory, suggesting that older adults process events on a conceptual level even when information is maintained over very short delays.

The Effect of Blocked and Interleaved Training on Associative Inference

Presenter(s): Rennie Kendrick − Biology

Faculty Mentor(s): Dasa Zeithamova, Caitlin Bowman

Poster 32

Research Area: Cognitive Neuroscience

Memory allows us to link across multiple experiences to derive new information. For example, if we see a person walking a dalmatian, and later see another person walking the same dalmation, we may infer that the two people are married. There are two models of how we accomplish this associative inference. According to the flexible retrieval model, individuals retrieve separate memories (person 1-dalmatian; person 2-dalmation) and infer about their relationship (person 1-person 2) when needed. According to the integrative encoding model, we retrieve the memory of the first person we saw with the dalmation while seeing the second, and form an integrated memory that links the two. I hypothesize that how readily we integrate older memories with new experience depends on how well established the prior knowledge is. To test this hypothesis, participants encoded object pairs (AB and BC) that shared an object B (e.g., banana-clock, clock-keyboard). Each pair was repeated three times. Half of the AB and BC pairs were presented in a blocked format (AB, AB, AB, BC, BC, BC) and half in an interleaved format (AB, BC, AB, BC, AB, BC). Later, participants were tested on the indirect AC association (banana-keyboard). I predicted that participants would infer more quickly in the interleaved condition because the two episodes were already linked at encoding via integrative encoding. Preliminary data show faster inference in the interleaved condition. Further investigation into the effect of blocked vs. interleaved training on learning could lead to enhanced teaching methods.

Emotion and Identity Influence on Associative Memory 

Presenter(s): Melissa Adler – Human Physiology

Faculty Mentor(s): Dasa Zeithamova, Taylor Guthrie

Poster 101

Research Area: Psychology

Eye witness testimonies play an important role in the criminal justice system. These testimonies depend upon the witness’ abilities to remember not only individual elements of events (e.g., having seen a specific person before), but remember how the elements of the event are associated with one another (e.g., having seen the person and the gun together). The events involved are usually emotionally charged but past studies on the influence of emotion on memory have focused primarily
on how people remember individual elements rather than associations between multiple elements. People’s perceptions
may also be influenced by their biases and stereotypes towards certain races and/or genders. In this experiment, I explored how effects of face identity and emotion influence people’s memories. I hypothesized that non-Caucasian, emotional, male faces will inhibit associative memory. Participants studied associations between two individual objects or between a face
and an object and were then tested on how well they recalled those associations, as well as if they tended to connect related memories. The face stimuli were of different races and genders and had either neutral or angry expressions. Preliminary results indicate that the emotional faces, specifically the non-Caucasian, male faces, have an impact on the participant’s abilities to form associations and recall those associations later. Results from this experiment may demonstrate challenges involving eye-witness testimonies. If it is shown that emotion coupled with certain identity factors interrupts these associative memory processes, then the validity of eye-witness testimonies falls in to question.

The Effect of Auditory Theta Stimulation On Memory, Mood and Attention (Works in Progress Presentation).

Presenter(s): Zora Rose

Faculty Mentor(s): Mike Posner & Dasa Zeithamova

Poster 2

Session: Sciences

The theta frequency (4-8hz) has been implicated with states of restful awareness (Posner, Fan, McCandliss, and Raz 2002). Increased frontal theta waves as measured by EEG have been achieved through meditation training in several studies (Tang et al, 2010; 2012). Studies of the effects of mediation also show increased executive control using measures involving the resolution of conflict (Cavanagh and Frank, 2014). Additionally, some research suggests that the use of auditory theta stimulation may improve overall cognition (Ortiz, Martínez, Fernández, Maestu, et al 2008). Other studies demonstrate a link shared between auditory binaural beat stimulation and improved overall mood (Padmanabhan, Hildreth, Laws, 2005). The aim of this current study is to determine if auditory stimulation utilizing the theta frequency may improve mood, increase working memory capacity and improve executive attention scores as measured by the attention network test, similar to the effects produced by meditators experiencing self- induced states of “restful alertness”.

Effect of Blocked vs. Interleaved Training on Associative Inference Ability

Presenter(s): Rennie Kendrick

Faculty Mentor(s): Dasa Zeithamova & Caitlin Bowman

Poster 119

Session: Social Sciences & Humanities

Memory allows us to link across multiple experiences to derive new information. For example, if we see a person, person 1, walking a Dalmatian, and later see another person, person 2, walking the same Dalmatian, we may infer that person 1 and 2 live in the same household. This linking of experiences to derive new information is called associative inference, and my research asks which conditions lead to the best associative inference. Participants are trained and tested on object pairs that each share an object in common with another pair. Half of the participants see object pairs in blocked format and the other half see the object pairs in interleaved format. In the blocked condition, participants have strongly established prior knowledge before encountering overlapping new information. In the interleaved condition, participants encounter a new overlapping episode before the first is strongly established. For the associative inference test, participants must infer that two objects that were never directly paired together, but paired with the same object, are indirectly related. I found that participants in the blocked condition performed significantly better on associative inference and directly-paired object tests compared to interleaved condition participants. Thus, strong memory for the first episode before encountering the second, overlapping episode enhanced associative inference ability and memory for both individual episodes. One possibility for this effect is that strongly established prior knowledge prevents interference from overlapping, but distinct episodes. Further investigation into the effect of blocked versus interleaved training on learning could lead to enhanced teaching methods.

The Impact of Negative Emotion on Associative Memory

Presenter(s): Jack Kapustka

Faculty Mentor(s): Dasa Zeithamova

Data Story 2 CLS

Previous research suggests that the ability to remember associations is impaired by negative emotions, though these findings remain inconclusive. In this study, we examined whether this impairment from exposure to a negative stimulus could be transferred to subsequent associations. Sixty-five students were recruited from the University of Oregon Human Subjects Pool. Subjects completed a paired-associates paradigm, in which they learned to link neutral object pairs (AB & BC) that shared a common associate (B). After being tested on AB learning, subjects then learned BC pairs, as well as unrelated pairs (XY) that did not share any AB associations. There were no differences in learning for any of the pairs as a function of emotional distractor condition. Overall, our results suggest that irrespective of distracting emotional experiences, learning of overlapping associations is more difficult than learning of non- overlapping associations.

Behavioral and Neural Predictors of Individual Differences in Concept Generalization

Presenter(s): Takako Iwashita

Faculty Mentor(s): Dasa Zeithamova & Caitlin Bowman

Poster 128

Session: Social Sciences & Humanities

Concept learning involves linking related pieces of information to a shared label, like learning that furry creatures that bark are called ‘dogs.’ People vary is how well they learn concepts and apply them to new situations (generalization). What factors drive these individual differences? In the present study, we tested whether stable aspects of intelligence or transient activations in the brain best predicted concept generalization abilities. To measure aspects of intelligence, subjects underwent an assessment that included measures of working memory, processing speed, perceptual reasoning, and verbal comprehension, which could be combined into an overall IQ. Subjects also completed a concept generalization task while undergoing fMRI, allowing us to measure activations in brain regions that are part of the explicit rule-learning system (hippocampus, prefrontal cortex) or part of an implicit system that learns without awareness (caudate, posterior visual cortex). To elucidate the shared or dissociable roles of behavioral and neural predictors in concept generalization, we tested the relationship between accuracy in concept generalization and individual differences in measures of intelligence and activation in each brain region of interest. Behaviorally, we found that overall IQ, but not its subcomponents, predicted concept generalization abilities. Neurally, we found that only the activation in the hippocampus predicted concept generalization abilities. Finally, we found that IQ and hippocampal activation each predicted concept generalization above-and-beyond each other. These results show dissociable contributions of behavioral and neural predictors of concept generalization, suggesting that both stable cognitive abilities and transient brain states influence the ability to learn new concepts.

Training on typical items facilitates learning of new concepts

Presenter(s): Wenjia Cao

Faculty Mentor(s): Dasa Zeithamova-Demircan & Caitlin Bowman

Poster 132

Session: Social Sciences & Humanities

Concept learning involves linking pieces of information to a shared category label, like learning that furry creatures that live with humans and bark are called dogs. What factors affect how well people learn new categories? Prior research suggests that people can learn categories either by memorizing individual category members or by averaging across category members to form an abstract representation of the perfect category member, known as the prototype. We reasoned that if people learn categories through memorization, then they should learn better from small training sets, but set size should not affect prototype learning. We also reasoned that if people learn categories through memorization, then they should learn better from training sets where items are distinct from one another (i.e., atypical), but that prototype learning would be facilitated by training on typical items. To test our hypotheses, separate groups of participants underwent category training that varied in the number and typicality of category members. During training, participants saw category members one at a time, guessed which category they belonged to, and were told whether they were right or wrong. Following training, participants were tested on their ability to categorize the training items as well as new examples that they had never seen. We found that people who trained with more typical items learned more quickly and were better at categorizing new examples. Training size did not have a significant influence on learning rate or categorization accuracy. Therefore, our results support the idea that the typicality of training items greatly influences category learning, which is likely because it promotes formation of abstract, prototype category representations.

The Effect of Emotion on Associative Memory: Anger versus Fear

Presenter(s): Melissa Adler

Faculty Mentor(s): Dasa Zeithamova & Caitlin Bowman

Poster: 136

Session: Social Sciences & Humanities

Studies show that emotion enhances memory for individual items but weakens memory for associations between items. One explanation for this associative memory impairment is that emotional stimuli capture attention, causing enhanced encoding of the emotional item but reduced encoding of the surrounding environment. This hypothesis generates the prediction that emotional information always impairs associative memory. Alternatively, it may be that emotion orients attention towards threats in the environment. For example, seeing an angry face constitutes a direct threat, potentially capturing attention and reducing memory for associated information. In contrast, seeing a fearful face indicates a threat elsewhere in the environment, potentially enhancing encoding of associated information. In the present study, I tested whether perception of anger and fear have different effects on memory for associated information. I hypothesized that associative memory would be worse for all emotional faces, both angry and fearful ones, compared to neutral faces. I also predicted that associative memory would be better for fearful faces than angry faces. To test these hypotheses, subjects studied sets of three images, consisting of two objects and a face with either a neutral, angry, or fearful expression. Subjects were later tested on their memory for the associations between the three items. Supporting our first hypothesis, memory for both angry and fearful associations was worse than memory for neutral associations. Contrary to our second hypothesis, there were no differences in memory for angry versus fearful associations. Thus, emotional information itself seems to capture attention, weakening memory for related information.