Laptop computers are widely prevalent in university classrooms. Although laptops are a valuable tool, they offer access to a distracting temptation: the Internet. In the study reported here, we assessed the relationship between classroom performance and actual Internet usage for academic and nonacademic purposes. Students who were enrolled in an introductory psychology course logged into a proxy server that monitored their online activity during class. Past research relied on self-report, but the current methodology objectively measured time, frequency, and browsing history of participants' Internet usage. In addition, we assessed whether intelligence, motivation, and interest in course material could account for the relationship between Internet use and performance. Our results showed that nonacademic Internet use was common among students who brought laptops to class and was inversely related to class performance. This relationship was upheld after we accounted for motivation, interest, and intelligence. Class-related Internet use was not associated with a benefit to classroom performance.

Some memories are linked such that recalling one can trigger the retrieval of another. What determines which memories are linked? Some models predict that simply occurring close together in time is sufficient for links to form between memories. A competing theory suggests that temporal proximity is generally not sufficient, and existing evidence for such links is an artifact of using chainlike lists of items in artificial laboratory tasks. To test these competing accounts, we asked subjects to recall news stories that they had encountered over the past 2 years (Experiment 1) or 4 months (Experiment 2). In both experiments, subjects showed a strong bias to successively recall stories that appeared in the news within days of each other—even after accounting for the fact that stories that occur close in time tend to be semantically related. By moving beyond laboratory tasks, this research solidifies the foundation of contemporary memory theory.

Social media sites such as Facebook and Twitter have increased drastically in popularity. However, information on these sites is not verified and may contain inaccuracies. It is well-established that false information encountered after an event can lead to memory distortion. Therefore, social media may be particularly harmful for autobiographical memory. Here, we tested the effect of Twitter on false memory. We presented participants with a series of images that depicted a story and then presented false information about the images in a scrolling feed that bore either a low or high resemblance to a Twitter feed. Confidence for correct information was similar across the groups, but confidence for suggested information was significantly lower when false information was presented in a Twitter format. We propose that individuals take into account the medium of the message when integrating information into memory.

Atkinson and Shiffrin (1968) argued that performance on any memory task reflects the combined influence of both the fixed structure of the memory system and control processes tailored to the specific task. We investigated the role of control processes in governing the temporal contiguity and semantic contiguity effects in free recall-tendencies to organize recall based on proximity in the study list and pre-existing semantic associations. Subjects studied lists that contained four "clusters", each composed of four semantically associated words but presented in random order such that associates were not in adjacent serial positions. Subjects were given either standard free-recall instructions, instructions to focus on order-based associations (i.e., the original order of presentation), or meaning-based associations (i.e., preexisting semantic relationships). Replicating previous work, lists with strong semantic relationships resulted in a reduced overall temporal contiguity effect when recalled under standard free-recall instructions. However, under meaning-based recall instructions, the temporal contiguity effect was nearly eliminated. Detailed analyses of within-cluster transitions and an order reconstruction task revealed that temporal information was encoded, but control processes prevented it from dominating memory search. These results point to a need for more empirical work exploring how control processes change recall dynamics and for more theoretical work modeling the computational basis of these processes.

The temporal contiguity effect (TCE) is the tendency for the recall of one event to cue recall of other events originally experienced nearby in time. Retrieved context theory proposes that the TCE results from fundamental properties of episodic memory: binding of events to a drifting context representation during encoding and the reinstatement of those associations during recall. If these processes are automatic, the TCE should not be dependent on any encoding strategy and should, in fact, be present regardless of encoding intentionality. Here, we ask whether this theory is compatible with recent findings that the TCE is dramatically reduced under incidental encoding, even though memory accuracy is only modestly reduced. We begin by attempting to replicate this finding in a new large-scale study with over 5,000 participants in which we manipulated encoding intentionality between participants in both delayed free recall and continual distractor free recall. A small, but reliable, TCE was observed in all conditions, although the effect was dramatically reduced in incidental encoding. In a simulation study, we demonstrated that retrieved context theory can simultaneously account for both overall recall and the strength of the TCE in incidental encoding conditions. Additional analyses revealed that the incidental TCE is not an artifact of theoretically uninteresting factors, such as recency, and is consistent with being generated by the core contextual dynamics of retrieved context theory.

Distractions are ubiquitous; our brains are inundated with task-irrelevant information. Thus, to remember successfully, one must actively maintain relevant information and prevent distraction from entering working memory. Researchers suggest the basal ganglia-prefrontal pathways are vital to this process by acting as a working memory gate. Using Parkinson's disease as a model of frontostriatal functioning and with signal detection analyses, the present study aims to better characterize the contribution of frontostriatal pathways of this gating process and to determine how it operates across multiple domains. To achieve this, Parkinson's disease patients and healthy controls completed verbal and spatial working memory tasks consisting of three conditions: low-load without distraction; low-load with distraction; and high-load without distraction. Patients were tested both ON and OFF dopaminergic medication, allowing for assessment of the contribution of dorsal and ventral frontostriatal pathways. The results demonstrate that when medication is withheld, Parkinson's patients have a response bias to answer "NO" across all conditions and domains, supporting our hypothesis that the basal ganglia-prefrontal pathways allow or prevent updates of working memory. Contrastingly, medication status affects d' in the distraction condition but not in the high- or low-load conditions. We attribute this to stimulus valuation processes that were impaired by dopaminergic medication overdosing the ventral pathway. These findings are both consistent with the hypothesis that the working memory gate filters spatial and verbal information before it enters into the working memory system, adding support for the gate being a domain-general mechanism of the central executive.

The present study aimed to characterize the mechanism by which working memory is enhanced for items that capture attention because of their novelty or saliency-that is, via bottom-up attention. The first experiment replicated previous research by corroborating that bottom-up attention directed to an item is sufficient for enhancing working memory and, moreover, generalized the effect to the domain of verbal working memory. The subsequent 3 experiments sought to determine how bottom-up attention affects working memory. We considered 2 hypotheses: (1) Bottom-up attention enhances the encoded representation of the stimulus, similar to how voluntary attention functions, or (2) It affects the order of encoding by shifting priority onto the attended stimulus. By manipulating how stimuli were presented (simultaneous/sequential display) and whether the cue predicted the tested items, we found evidence that bottom-up attention improves working memory performance via the order of encoding hypothesis. This finding was observed across change detection and free recall paradigms. In contrast, voluntary attention improved working memory regardless of encoding order and showed greater effects on working memory. We conclude that when multiple information sources compete, bottom-up attention prioritizes the location at which encoding should begin. When encoding order is set, bottom-up attention has little or no benefit to working memory. (PsycINFO Database Record

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