In the continuous response (CR) task, the subject is given the name of a familiar category and must respond with category examples within a fixed time limit. The response sequence and the interresponse times are the measured variables. A general model is proposed for performance in the CR task. The time taken to generate a response is identified with the shortest search time from among a set of simultaneous search processes. Each response has a generation probability that is a function of the parameters governing the search process durations. Data involving the category “states in the United States” are used to test the model. The model accounts for the performance of nearly all individuals in these data.

This study aimed to identify and compare the EEG activities associated with semantic and episodic memory retrieval during creative processes. Episodic and semantic memory induction studies were conducted and EEG was used to collect data. The results showed that (i) Episodic and semantic memory retrieval are related to the frontal lobe area; (ii) Semantic memory retrieval is evoked more swiftly compared with episodic memory retrieval (ii) Prior to episodic memory retrieval, semantic memory retrieval is evoked first.

The mental lexicon offers a window into the configuration of conceptual domains such as space and time, which has been labeled as concrete the former and abstract the latter in the current embodiment approach to cognition. Space has a phonological and semantic value in sign languages, but not in spoken languages. Additionally, the representation of time by spatial means is robust in oral and sign languages. This research asks if Deaf signers and hearing nonsigners have the same conceptual organization of those domains. In their respective languages, sixty-two participants made a repeated free word association task. These results showed that the studied populations have a little overlap in the associates evocated for each clue. The analysis of the preferences of the semantic relations of the pairs clue-associate showed a greater tendency of the Deaf signers to establish thematic relations. In contrast, the hearing participants indicated a bias toward taxonomic relations. The results suggest that the abstractness or concreteness of concepts may be modulated by factors associated with linguistic modalities. However, in this compared free association norms factors related to the language deprivation of Deaf, the asymmetries in the cross-modal language contact and cross-modal borrowing were not exhaustively controlled.

Early adversities that are caregiving-related (crEAs) are associated with a significantly increased risk for mental health problems. Recent neuroscientific advances have revealed alterations in medial prefrontal cortex (mPFC)-subcortical circuitry following crEAs. While this work has identified alterations in affective operations (e.g., perceiving, reacting, controlling, learning) associated with mPFC–subcortical circuitry, this circuitry has a much broader function extending beyond operations. It plays a primary role in affective meaning making, involving conceptual-level, schematized knowledge to generate predictions about the current environment. This function of mPFC–subcortical circuitry motivates asking whether mPFC–subcortical phenotypes following crEAs support semanticized knowledge content (or the concept-level knowledge) and generate predictive models. I present a hypothesis motivated by research findings across four different lines of work that converge on mPFC–subcortical neuroanatomy, including (a) the neurobiology supporting emotion regulation processes in adulthood, (b) the neurobiology that is activated by caregiving cues during development, (c) the neurobiology that is altered by crEAs, and (d) the neurobiology of semantic-based meaning making. I hypothesize that the affective behaviors following crEAs result in part from affective semantic memory processes supported by mPFC–subcortical circuitry that over the course of development, construct affective schemas that generate meaning making and guide predictions. I use this opportunity to review some of the literature on mPFC–subcortical circuit development following crEAs to illustrate the motivation behind this hypothesis. Long recognized by clinical science and cognitive neuroscience, studying schema-based processes may be particularly helpful for understanding how affective meaning making arises from developmental trajectories of mPFC–subcortical circuitry.

Objectives: A growing body of research suggests that regular participation in long-term exercise is associated with enhanced cognitive function. However, less is known about the beneficial effects of acute exercise on semantic memory. This study investigated brain activation during a semantic memory task after a single session of exercise in healthy older adults using functional magnetic resonance imaging (fMRI). Methods: Using a within-subjects counterbalanced design, 26 participants (ages, 55–85 years) underwent two experimental visits on separate days. During each visit, participants engaged in 30 min of rest or stationary cycling exercise immediately before performing a Famous and Non-Famous name discrimination task during fMRI scanning. Results: Acute exercise was associated with significantly greater semantic memory activation (Famous>Non-Famous) in the middle frontal, inferior temporal, middle temporal, and fusiform gyri. A planned comparison additionally showed significantly greater activation in the bilateral hippocampus after exercise compared to rest. These effects were confined to correct trials, and as expected, there were no differences between conditions in response time or accuracy. Conclusions: Greater brain activation following a single session of exercise suggests that exercise may increase neural processes underlying semantic memory activation in healthy older adults. These effects were localized to the known semantic memory network, and thus do not appear to reflect a general or widespread increase in brain blood flow. Coupled with our prior exercise training effects on semantic memory-related activation, these data suggest the acute increase in neural activation after exercise may provide a stimulus for adaptation over repeated exercise sessions. (JINS, 2019, 25, 557–568)

Objectives: Autobiographical memory dysfunction is a marker of vulnerability to depression. Patients with obstructive sleep apnea (OSA) experience high rates of depression and memory impairment, and autobiographical memory impairments have been observed compared to healthy controls; however, these groups were not age-matched. This study aimed to determine whether individuals with untreated OSA have impaired autobiographical memory when compared to age-matched controls, and to assess the quality of autobiographical memories from three broad time points. Methods: A total of 44 participants with OSA (M age=49.4±13.0) and 44 age-matched controls (M age=50.0±13.1) completed the Autobiographical Memory Interview (AMI) to assess semantic and episodic memories from three different life stages, and 44 OSA participants and 37 controls completed the Autobiographical Memory Test (AMT) to assess overgeneral memory recall (an inability to retrieve specific memories). Results: OSA participants had significantly poorer semantic recall of early adult life on the AMI (p<.001), and more overgeneral autobiographical memories recalled on the AMT (=.001), than controls. Poor semantic recall from early adult life was significantly correlated with more depressive symptoms (p=0.006) and lower education (p<0.02), while higher overgeneral memory recall was significantly associated with older age (p=.001). Conclusions: A specific deficit in semantic autobiographical recall was observed in individuals with OSA. OSA patients recalled more overgeneral memories, suggesting that aspects of the sleep disorder affect their ability to recollect specific details of events from their life. These cognitive features of OSA may contribute to the high incidence of depression in this population. (JINS 2019, 25, 266–274)

Objectives: Although the influence of prior knowledge on associative memory in healthy aging has received great attention, it has never been studied in Alzheimer’s disease (AD). This study aimed at assessing whether AD patients could benefit from prior knowledge in associative memory and whether such benefit would be related to the integrity of their semantic memory. Methods: Twenty-one AD patients and 21 healthy older adults took part in an associative memory task using semantically related and unrelated word pairs and were also submitted to an evaluation of their semantic memory. Results: While participants of both groups benefited from semantic relatedness in associative discrimination, related pairs recognition was significantly predicted by semantic memory integrity in healthy older adults only. Conclusions: We suggest that patients benefitted from semantic knowledge to improve their performance in the associative memory task, but that such performance is not related to semantic knowledge integrity evaluation measures because the two tasks differ in the way semantic information is accessed: in an automatic manner for the associative memory task, with automatic processes thought to be relatively preserved in AD, and in a controlled manner for the semantic knowledge evaluation, with controlled processes thought to be impaired in AD. (JINS, 2019, 25, 443–452)