Semantic-to-autobiographical memory priming occurs across multiple sources: Implications for autobiographical remembering.

Mace, McQueen, Hayslett, Stalely, and Welch (Memory & Cognition, 47, 299-312, 2019) demonstrated that the activation of semantic memories leads to the activation of autobiographical memories. In that study, the semantic processing of concept words (e.g., garden) was shown to prime related autobiographical memories (e.g., personal memories involving garden) on voluntary and involuntary autobiographical memory tasks. Our goal in the current study was to replicate such semantic-to-autobiographical priming effects, and show that they can be extended to a wider set of stimuli than reported in Mace et al. In Experiment 1, semantic-to-autobiographical priming was obtained on a measure of involuntary autobiographical memory (the vigilance task) following the processing of concept words in insolation and within the context of a sentence. In Experiment 2, semantic-to-autobiographical priming was again observed to occur with the vigilance task, but in this instance it occurred following the processing of both linguistic (words) and nonlinguistic (pictures) stimuli. The results of each of these experiments supports the idea that semantic-to-autobiographical activations occur within a wide variety of contexts (e.g., in language, perception, etc.). The implications of the results for autobiographical remembering are discussed.

The role of lifetime periods in the organisation of episodic memories.

Research on the nature of episodic memory associations has suggested that episodic memories are associated by conceptual knowledge, where memories cluster around the same content (e.g. memories about the same people) or general-event knowledge, where memories cluster around extended events (e.g. a holiday in London), repeated events (e.g. Sunday walks in the park), or causally related events (i.e. where one event leads to another). Research has also suggested that episodic memories are associated by lifetime periods (e.g. when I was in high school), where memories cluster within lifetime periods. However, it is unclear whether episodic memories can be associated solely by lifetime periods, or if such associations are subordinate to conceptual or general-event associations. To answer this question, we reanalysed a large sample of involuntary memory chains (Mace, J. H., Clevinger, A. M., & Bernas, R. S. (2013). Involuntary memory chains: What do they tell us about autobiographical memory organisation? Memory, 21, 324-335). The results of this analysis suggested that lifetime periods associations are subordinate to conceptual and general-event associations, as lifetime periods were found to cluster within the latter two associations. The potential functions of this organisation are discussed.

Oral administration of hesperidin, a citrus flavonone, in rats counteracts the oxidative stress, the inflammatory cytokine production, and the hepatotoxicity induced by the ingestion of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

The objective of the current study was to investigate the protective effects of hesperidin against oxidative stress, altered cytokines levels and histological changes in rats induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were divided randomly into four equal groups (Control, TCDD, hesperidin and TCDD+hesperidin). TCDD and hesperidin were given by gavage, dissolved in corn oil at doses of 2 µ/kg/week and 50 mg/kg/day respectively. The blood and tissue samples were taken from all rats on the 60(th) day, to be analyzed for the determination of oxidative stress, histological changes and cytokine levels. The results indicated that hesperidin prevented oxidative damage caused by TCDD via decrease lipid peroxidation and increased antioxidant defense systems. It also reversed the histological damage induced by TCDD. Although, TCDD led to a significant increase in TNF-α and IL-1ß levels, hesperidin treatment was able to normalize these values in rats. In conclusion, it was shown that TCDD caused adverse effects as regards cytokine levels, histological alterations and oxidative stress in rats. However, hesperidin treatment mitigated these toxic effects. These results suggest that hesperidin could play a protective role against TCDD toxicity.