This week, I found myself reading articles from the newest issue of the Trends in Cognitive Science journal, which was published for March 2018. The main theme of the issue focuses on the modeling of the predictive social mind and creating a multilayered framework for social prediction, as many cognitive scientists believe that “to successfully interact with other people, we must anticipate their thoughts, feelings, and actions” (Drayton, 2018). The same can be said about the interactions that Artificial Intelligence systems have with people. In order for an AI system to successfully interact with people, then it must anticipate their… Read More
Elongator complex is required for long-term olfactory memory formation in Drosophila
Published in: Learning & Memory, Volume 25, Issue 4, 183-196 Abstract “The evolutionarily conserved Elongator Complex associates with RNA polymerase II for transcriptional elongation. Elp3 is the catalytic subunit, contains histone acetyltransferase activity, and is associated with neurodegeneration in humans. Elp1 is a scaffolding subunit and when mutated causes familial dysautonomia. Here, we show that elp3 and elp1 are required for aversive long-term olfactory memory in Drosophila. RNAi knockdown of elp3 in adult mushroom bodies impairs long-term memory (LTM) without affecting earlier forms of memory. RNAi knockdown with coexpression of elp3 cDNA reverses the impairment. Similarly, RNAi knockdown of elp1 impairs LTM and coexpression of elp1 cDNA reverses this phenotype. The LTM deficit in elp3 and elp1 knockdown… Read More
Mechanisms of critical period in the hippocampus underlie object location learning and memory in infant rats
Published in: Learning & Memory, Volume 25, Issue 4, 176-182 Abstract “Episodic memories in early childhood are rapidly forgotten, a phenomenon that is associated with “infantile amnesia,” the inability of adults to remember early-life experiences. We recently showed that early aversive contextual memory in infant rats, which is in fact rapidly forgotten, is actually not lost, as reminders presented later in life reinstate a long-lasting and context-specific memory. We also showed that the formation of this infantile memory recruits in the hippocampus mechanisms typical of developmental critical periods. Here, we tested whether similar mechanisms apply to a nonaversive, hippocampal type of… Read More
The effects of extinction-aroused attention on context conditioning
Published in: Learning & Memory, Volume 25, Issue 4, 165-175 Abstract “Two experiments assessed the effects of extinguishing a conditioned cue on subsequent context conditioning. Each experiment used a different video-game method where sensors predicted attacking spaceships and participants responded to the sensor in a way that prepared them for the upcoming attack. In Experiment 1 extinction of a cue which signaled a spaceship-attack outcome facilitated subsequent learning when the attack occurred unsignaled. In Experiment 2 extinction of a cue facilitated subsequent learning, regardless of whether the spaceship outcome was the same or different as used in the earlier training. In… Read More
Elucidating the mechanisms of fear extinction in developing animals: a special case of NMDA receptor-independent extinction in adolescent rats
Published in: Learning & Memory, Volume 25, Issue 4, 158-164 Abstract “NMDA receptors (NMDARs) are considered critical for the consolidation of extinction but recent work challenges this assumption. Namely, NMDARs are not required for extinction retention in infant rats as well as when extinction training occurs for a second time (i.e., reextinction) in adult rats. In this study, a possible third instance of NMDAR-independent extinction was tested. Although adolescents typically exhibit impaired extinction retention, rats that are conditioned as juveniles and then given extinction training as adolescents (JuvCond-AdolesExt) have good extinction retention. Unexpectedly, this good extinction retention is not associated with… Read More
α2-Adrenergic receptor activation promotes long-term potentiation at excitatory synapses in the mouse accessory olfactory bulb
Published in: Learning & Memory, Volume 25, Issue 4, 147-157 Abstract “The formation of mate recognition memory in mice is associated with neural changes at the reciprocal dendrodendritic synapses between glutamatergic mitral cell (MC) projection neurons and GABAergic granule cell (GC) interneurons in the accessory olfactory bulb (AOB). Although noradrenaline (NA) plays a critical role in the formation of the memory, the mechanism by which it exerts this effect remains unclear. Here we used extracellular field potential and whole-cell patch-clamp recordings to assess the actions of bath-applied NA (10 µM) on the glutamatergic transmission and its plasticity at the MC-to-GC synapse… Read More
Hearing sounds as words: Neural responses to environmental sounds in the context of fluent speech
Published in: Brain and Language, Volume 179, April 2018, 51-61 Abstract “Environmental sounds (ES) can be understood easily when substituted for words in sentences, suggesting that linguistic context benefits may be mediated by processes more general than some language-specific theories assert. However, the underlying neural processing is not understood. EEG was recorded for spoken sentences ending in either a spoken word or a corresponding ES. Endings were either congruent or incongruent with the sentence frame, and thus were expected to produce N400 activity. However, if ES and word meanings are combined with language context by different mechanisms, different N400 responses would… Read More
Does syntax bias serial order reconstruction of verbal short-term memory?
Published in: Journal of Memory and Language, Volume 100, June 2018, 98-122 Abstract “Existing models of short-term sequence memory can account for effects of long-term knowledge on the recall of individual items, but have rarely addressed the effects of long-term sequential constraints on recall. We examine syntactic constraints on the ordering of words in verbal short-term memory in four experiments. People were found to have better memory for sequences that more strongly conform to English syntax, and that errors in recall tended to make output sequences more syntactic (i.e., a syntactic bias). Model simulations suggest that the syntactic biasing in verbal short-term recall… Read More
Mapping lexical-semantic networks and determining hemispheric language dominance: Do task design, sex, age, and language performance make a difference?
Published in: Brain and Language, Volume 179, April 2018, 42-50 Abstract “Blocked and event-related fMRI designs are both commonly used to localize language networks and determine hemispheric dominance in research and clinical settings. We compared activation profiles on a semantic monitoring task using one of the two designs in a total of 43 healthy individual to determine whether task design or subject-specific factors (i.e., age, sex, or language performance) influence activation patterns. We found high concordance between the two designs within core language regions, including the inferior frontal, posterior temporal, and basal temporal region. However, differences emerged within inferior parietal cortex.… Read More
Representation of action semantics in the motor cortex and Broca’s area
Published in: Brain and Language, Volume 179, April 2018, 33-41 Abstract “Previous studies have shown that both reading action words and observing actions engage the motor cortex and Broca’s area, but it is still controversial whether a somatotopic representation exists for action verbs within the motor cortex and whether Broca’s area encodes action-specific semantics for verbs. Here we examined these two issues using a set of functional MRI experiments, including word reading, action observation and a movement localiser task. Results from multi-voxel pattern analysis (MVPA) showed a somatotopic organisation within the motor areas and action-specific activation in Broca’s area for observed… Read More