Semantic memory

The goal of this study is to determine how negative information affects purchasing decisions and what neurological processes are included in these purchasing decisions. Specifically, this study aims to explore the effect of consumers receiving the same negative attribute twice versus two different negative attributes for a product. The introduction of this study will discuss background concepts like the Controlled Semantic Cognition Framework from Lambon Ralph et al., (2017) and the neural processes behind selection as discussed in Thompson-Schill et al., (1997). The results indicated that there were differences in hemodynamic response between conditions where the same negative attribute was presented with a product twice versus conditions where two different negative attributes were presented with a product. Both behaviorally and hemodynamically, the results provide evidence supporting an inner conflict when dealing with two negative alternative choices. Future research could include realistic advertisements to better mimic everyday scenarios.

This experiment evaluated the effect of positively evaluative attributes on purchasing decisions by manipulating the Type of Repetition from a study phase to a test phase. Behavioral data and hemodynamic responses were measured using functional near-infrared spectroscopy (fNIRS) in 38 participants during a study task, where brand-name products and product specific attributes were processed, and during a test phase, where participants chose to purchase either new or previously processed products that were presented with either the same attribute, a different attribute, or no attribute. Results at test showed that repeating the association produced the highest accuracy in selecting the previously processed product and the highest hemodynamic activation. In contrast, presenting a different attribute at test produced the lowest accuracy and least hemodynamic activation, much like baseline. This hemodynamic difference between the same and different conditions was especially prevalent in the left hemisphere during the later time windows. These findings suggest that repeating the association biases purchase intention and produces hemodynamic repetition enhancement. In contrast, changing the association leads to interference and reduced selection of the processed product.

The types of intrusion errors (Prior List, Semantically Related, and Unrelated)
made on the LASSI-L verbal memory task were compared across three diagnostic groups
(N = 160, 61 % female), Cognitively Normal (CN), amnestic Mild Cognitive Impairment
(aMCI), and Alzheimer’s disease (AD). Errors related to Proactive, Recovery from
Proactive, and Retroactive Interference were also analyzed, as well as the relationship of
errors to Amyloid load, a biomarker of AD. Results suggest that the types of error made
indicated the level of cognitive decline. It appears that as deficits increase, impaired
semantic networks result in the simultaneous activation of items that are semantically
related to LASSI-L words. In the aMCI group, providing a semantic cue resulted in an
increased production of Semantically Related intrusions. Unrelated intrusions occurred
rarely, although, a small number occurred even in the CN group, warranting further
investigation. Amyloid load correlated with all intrusion errors.