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Ramirez Butavand, D.

Publications and source records attributed to Ramirez Butavand, D..

4 recordsLinked to original sources

A novel event improves memory retrieval and divergent thinking in a naturalistic school environment

Stored memories are useless unless they are available for retrieval. Thus, investigating different ways to modulate retrieval is crucial. Novelty has been extensively studied as a modulator of memory. In this study, we investigated whether exposure to a novel event, an innovative neuroscience lesson, can enhance memory retrieval and divergent thinking in high school students. Across three experiments, we assessed the timing and mechanisms underlying these effects. In experiment 1, we found that memory retrieval was enhanced when the novel lesson occurred immediately before a memory test, but not when it was presented one hour earlier. In experiment 2, we found that the same immediate novelty exposure improved divergent thinking performance. Finally, in experiment 3, we explored potential shared mechanisms using a competition protocol and revealed that novelty improved divergent thinking regardless of its timing relative to memory retrieval. However, memory retrieval benefited only when tested immediately before the divergent thinking task. These results suggest that novelty boosts both memory retrieval and divergent thinking, but through partially distinct mechanisms. Our findings demonstrate that a simple, real-world classroom intervention can effectively enhance key cognitive functions in students. Significance StatementStored memories are only valuable if they can be retrieved, and memory retrieval plays a key role in creative thinking. Here, we tested whether a simple, novel event, a neuroscience lesson, could enhance memory retrieval and creative thinking in a real-world classroom setting. We found that novelty improved both memory retrieval and divergent thinking, an aspect of creative thinking, when presented immediately before the task. Finally, we revealed a non-reciprocal competition effect between memory retrieval and divergent thinking. These findings highlight a practical, low-cost intervention to boost key cognitive functions in students, demonstrating that brief, well-timed novel experiences can support both learning and creative thinking in educational environments.

neuroscience↗

High intensity exercise before sleep boosts memory encoding the next morning

The importance of sleep for memory consolidation has been extensively studied, but its role for memory encoding remains less well characterized. At the molecular and cellular level, the renormalization of synaptic weights during sleep has received substantial support, which is thought to free capacity to encode new information at the behavioral level. However, at the systems level and behaviorally, support for this process playing a major role for memory function remains scarce. In the current study, we investigated the utility of moderate- and high-intensity evening exercise as a low-cost low-tech intervention to modulate sleep and its influence on subsequent encoding in the morning. Our findings indicate that high-intensity interval training (HIIT) improved post-sleep memory performance with effects lasting up to 24 hours after initial encoding. In addition, we show that especially the early parts of the encoding task were affected by the HIIT intervention, which is in line with increases in synaptic homeostasis being targeted by the exercise. Intriguingly, low-performing participants seemed to benefit more from the HIIT intervention suggesting it not only as a tool for basic research but also as a candidate for applications to boost memory performance in mental disorders or in the elderly. These results provide first evidence that acute exercise can affect learning processes even hours after it occurs.

neuroscience↗

Acute and chronic physical activity improve spatial pattern separation in humans

Physical activity benefits both fitness and cognition. However, its effect on long-term memory is unclear. Successful memory involves not only remembering information over time but also keeping memories distinct and less confusing. The ability to separate similar experiences into distinct memories is one of the main features of episodic memory. In this work, we evaluated the effect of acute and chronic physical activity on a new task to assess spatial pattern separation in a 3D virtual reality environment. We manipulated the load of memory similarity and found that 25 minutes of cycling after encoding - but not before retrieval - was sufficient to improve similar, but not dissimilar memories, 24 hours after encoding. Furthermore, we found that participants who engaged in regular physical activity, but not sedentary subjects, showed memory for the similar condition the next day. Thus, physical activity could be a simple way to improve discrimination of spatial memories in humans.

animal behavior and cognition↗

Discrete anatomical coordinates for speech production and synthesis

The sounds of all languages are described by a finite set of symbols, which are extracted from the continuum of sounds produced by the vocal organ. How the discrete phonemic identity is encoded in the continuous movements producing speech remains an open question for the experimental phonology. In this work, this question is assessed by using Hall-effect transducers and magnets -mounted on the tongue, lips and jaw- to track the kinematics of the oral tract during the vocalization of vowel-consonant-vowel structures. Using a threshold strategy, the time traces of the transducers were converted into discrete motor coordinates unambiguously associated with the vocalized phonemes. Furthermore, the signals of the transducers combined with the discretization strategy were used to drive a low-dimensional vocal model capable of synthesizing intelligible speech. The current work not only addressed a relevant inquiry of the biology of language, but also shows the performance of the experimental technique to monitor the displacement of the main articulators of the vocal tract while speaking. This novel electronic device represents an economic and portable option to the standard system used to study the vocal tract movements.

neuroscience↗