scholarly journals Neural mechanisms of infant learning: differences in frontal theta activity during object exploration modulate subsequent object recognition

2015 ◽  
Vol 11 (5) ◽  
pp. 20150041 ◽  
Author(s):  
Katarina Begus ◽  
Victoria Southgate ◽  
Teodora Gliga
Keyword(s):  
Visual Attention ◽  
Theta Activity ◽  
Neural Mechanisms ◽  
Motivation To Learn ◽  
Theta Band ◽  
Learning Mechanisms ◽  
Learning Differences ◽  
Object Exploration ◽  
Theta Frequency ◽  
Infant Learning

Investigating learning mechanisms in infancy relies largely on behavioural measures like visual attention, which often fail to predict whether stimuli would be encoded successfully. This study explored EEG activity in the theta frequency band, previously shown to predict successful learning in adults, to directly study infants' cognitive engagement, beyond visual attention. We tested 11-month-old infants ( N = 23) and demonstrated that differences in frontal theta-band oscillations, recorded during infants' object exploration, predicted differential subsequent recognition of these objects in a preferential-looking test. Given that theta activity is modulated by motivation to learn in adults, these findings set the ground for future investigation into the drivers of infant learning.

scholarly journals Extinction recall of fear memories formed before stress is not affected despite amygdalar hyperactivity

2018 ◽  
Author(s):  
Mohammed Mostafizur Rahman ◽  
Ashutosh Shukla ◽  
Sumantra Chattarji
Keyword(s):  
Normal Stress ◽  
Fear Extinction ◽  
Theta Activity ◽  
Prior Exposure ◽  
Stress Exposure ◽  
Theta Frequency ◽  
Directional Coupling ◽  
Effects Of Stress

AbstractStress is known to exert its detrimental effects not only by enhancing fear, but also by impairing its extinction. However, in earlier studies stress exposure invariably preceded both processes. Thus, compared to unstressed animals, stressed animals had to extinguish fear memories from higher levels of freezing caused by prior exposure to stress. Here we decouple the two processes to examine if stress specifically impairs fear extinction. Strikingly, when fear memories were formed before stress exposure, thereby allowing animals to initiate extinction from comparable levels of fear, recall of fear extinction was unaffected. Despite this we observed a persistent increase in theta activity in the BLA. Theta activity in the mPFC, by contrast, was normal. Stress also disrupted mPFC-BLA theta-frequency synchrony and directional coupling. Thus, in the absence of the fear-enhancing effects of stress, the expression of fear reflects normal regulation of mPFC activity, not stress-induced hyperactivity in the amygdala.

Can Infant Cognitive Psychology Be Helpful in Understanding Learning Processes?

2006 ◽  
Vol 11 (4) ◽  
pp. 253-262 ◽  
Author(s):  
Roger Lécuyer
Keyword(s):  
Cognitive Psychology ◽  
Teaching And Learning ◽  
Modern Society ◽  
Social Mechanisms ◽  
Older Children ◽  
Learning Mechanisms ◽  
Developmental Sequences ◽  
Long Time ◽  
Effectiveness And Efficiency ◽  
Infant Learning

Since teaching and learning has become a major economic activity of modern society, different learning models can be considered in order to increase its effectiveness and efficiency. For a long time infant cognitive psychology was influenced by nativist theories and, thus, early learning has been underestimated and insufficiently studied. However, in recent years, infant psychology has described developmental sequences, learning situations, and social mechanisms that influence development. Thus, infant psychology appears again to be developmental. Since infant learning is fast and efficient, this paper proposes that it can be considered as a model for teaching and learning in older children and adults. Some examples of early acquired knowledge and some acquisition situations are presented. Conversely, some examples of later failures are exposed. The relevant theoretical contexts are discussed. The consequences of learning mechanisms observed in infants for pedagogy are considered.

Insights into the neural mechanisms of becoming bilingual: A brief synthesis of second language research with artificial linguistic systems

2019 ◽  
Vol 23 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Kara Morgan-Short
Keyword(s):  
Second Language ◽  
Test Tube ◽  
Neural Mechanisms ◽  
System Research ◽  
L2 Acquisition ◽  
Learning Mechanisms ◽  
Grammar Learning ◽  
Linguistic System ◽  
Language Research ◽  
Neural Processes

AbstractArtificial linguistic systems can offer researchers test tube-like models of second language (L2) acquisition through which specific questions can be examined under tightly controlled conditions. This paper examines what research with artificial linguistic systems has revealed about the neural mechanisms involved in L2 grammar learning. It first considers the validity of meaningful and non-meaningful artificial linguistic systems. Then it contextualizes and synthesizes neural artificial linguistic system research related to questions about age of exposure to the L2, type of exposure, and online L2 learning mechanisms. Overall, using artificial linguistic systems seems to be an effective and productive way of developing knowledge about L2 neural processes and correlates. With further validation, artificial linguistic system paradigms may prove an important tool more generally in understanding how individuals learn new linguistic systems as they become bilingual.

Sustained BOLD and theta activity in auditory cortex are related to slow stimulus fluctuations rather than to pitch

2012 ◽  
Vol 107 (12) ◽  
pp. 3458-3467 ◽  
Author(s):  
Iris Steinmann ◽  
Alexander Gutschalk
Keyword(s):  
Auditory Cortex ◽  
Primary Auditory Cortex ◽  
Specific Area ◽  
Theta Activity ◽  
Theta Band ◽  
Related Activity ◽  
Specific Stimulus ◽  
Time Frequency ◽  
Constant Pitch ◽  
Band Activity

Human functional MRI (fMRI) and magnetoencephalography (MEG) studies indicate a pitch-specific area in lateral Heschl's gyrus. Single-cell recordings in monkey suggest that sustained-firing, pitch-specific neurons are located lateral to primary auditory cortex. We reevaluated whether pitch strength contrasts reveal sustained pitch-specific responses in human auditory cortex. Sustained BOLD activity in auditory cortex was found for iterated rippled noise (vs. noise or silence) but not for regular click trains (vs. jittered click trains or silence). In contrast, iterated rippled noise and click trains produced similar pitch responses in MEG. Subsequently performed time-frequency analysis of the MEG data suggested that the dissociation of cortical BOLD activity between iterated rippled noise and click trains is related to theta band activity. It appears that both sustained BOLD and theta activity are associated with slow non-pitch-specific stimulus fluctuations. BOLD activity in the inferior colliculus was sustained for both stimulus types and varied neither with pitch strength nor with the presence of slow stimulus fluctuations. These results suggest that BOLD activity in auditory cortex is much more sensitive to slow stimulus fluctuations than to constant pitch, compromising the accessibility of the latter. In contrast, pitch-related activity in MEG can easily be separated from theta band activity related to slow stimulus fluctuations.

scholarly journals A conceptual frame with two neural mechanisms to model selective visual attention processes

2008 ◽  
Vol 71 (4-6) ◽  
pp. 704-720 ◽  
Author(s):  
José Mira ◽  
Ana E. Delgado ◽  
María T. López ◽  
Antonio Fernández-Caballero ◽  
Miguel A. Fernández
Keyword(s):  
Visual Attention ◽  
Neural Mechanisms ◽  
Selective Visual Attention ◽  
Conceptual Frame

Neural Mechanisms of Visual Attention: How Top-Down Feedback Highlights Relevant Locations

Science ◽  
2007 ◽  
Vol 316 (5831) ◽  
pp. 1612-1615 ◽  
Author(s):  
Y. B. Saalmann ◽  
I. N. Pigarev ◽  
T. R. Vidyasagar
Keyword(s):  
Visual Attention ◽  
Neural Mechanisms ◽  
Top Down

scholarly journals Distinct neural mechanisms meet challenges in dynamic visual attention due to either load or object spacing

2018 ◽  
Author(s):  
V. Mäki-Marttunen ◽  
T. Hagen ◽  
B. Laeng ◽  
T. Espeseth
Keyword(s):  
Visual Attention ◽  
Cognitive Processing ◽  
Brain Activity ◽  
Neural Mechanisms ◽  
Spatial Proximity ◽  
Physiological Mechanisms ◽  
Spatial Tasks ◽  
Spatial Interference ◽  
The Brain ◽  
Separate Cohort

AbstractWhen solving dynamic visuo-spatial tasks, the brain copes with perceptual and cognitive processing challenges. In the multiple-object tracking (MOT) task, the number of objects to be tracked (i.e. load) imposes attentional demands, but so does spatial interference from irrelevant objects (i.e. crowding). Presently, it is not clear whether load and crowding activate separate cognitive and physiological mechanisms. Such knowledge would be important to understand the neurophysiology of visual attention. Furthermore, it would help resolve conflicting views between theories of visual cognition, particularly concerning sources of capacity limitations. To address this problem, we varied the degree of processing challenge in the MOT task in two ways: First, the number of objects to track, and second, the spatial proximity between targets and distractors. We first measured task-induced pupil dilations and saccades during MOT. In a separate cohort we measured fMRI brain activity during MOT. The behavioral results in both cohorts revealed that increased load and crowding led to reduced accuracy in an additive manner. Load was associated with pupil dilations, whereas crowding was not. Activity in dorsal attentional areas and frequency of saccades were proportionally larger both with higher levels of load and crowding. Higher crowding recruited additionally ventral attentional areas that may reflect orienting mechanisms. The activity in the brainstem nuclei ventral tegmental area/substantia nigra and locus coeruleus showed clearly dissociated patterns. Our results constitute convergent evidence from independent samples that processing challenges due to load and object spacing may rely on different mechanisms.

scholarly journals Understanding visual attention with RAGNAROC: A Reflexive Attention Gradient through Neural AttRactOr Competition

2018 ◽  
Author(s):  
Brad Wyble ◽  
Chloe Callahan-Flintoft ◽  
Hui Chen ◽  
Toma Marinov ◽  
Aakash Sarkar ◽  
...  
Keyword(s):  
Visual Attention ◽  
Relevant Information ◽  
Neural Correlates ◽  
Neural Mechanisms ◽  
Covert Attention ◽  
Lower Priority ◽  
Reflexive Attention ◽  
Visual Hierarchy ◽  
New Information ◽  
Suppression Effects

AbstractA quintessential challenge for any perceptual system is the need to focus on task-relevant information without being blindsided by unexpected, yet important information. The human visual system incorporates several solutions to this challenge, one of which is a reflexive covert attention system that is rapidly responsive to both the physical salience and the task-relevance of new information. This paper presents a model that simulates behavioral and neural correlates of reflexive attention as the product of brief neural attractor states that are formed across the visual hierarchy when attention is engaged. Such attractors emerge from an attentional gradient distributed over a population of topographically organized neurons and serve to focus processing at one or more locations in the visual field, while inhibiting the processing of lower priority information. The model moves towards a resolution of key debates about the nature of reflexive attention, such as whether it is parallel or serial, and whether suppression effects are distributed in a spatial surround, or selectively at the location of distractors. Most importantly, the model develops a framework for understanding the neural mechanisms of visual attention as a spatiotopic decision process within a hierarchy and links them to observable correlates such as accuracy, reaction time, and the N2pc and PD components of the EEG. This last contribution is the most crucial for repairing the disconnect that exists between our understanding of behavioral and neural correlates of attention.

scholarly journals Different theta frameworks coexist in the rat hippocampus and are coordinated during memory-guided and novelty tasks

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Víctor J López-Madrona ◽  
Elena Pérez-Montoyo ◽  
Efrén Álvarez-Salvado ◽  
David Moratal ◽  
Oscar Herreras ◽  
...  
Keyword(s):  
Sensory Information ◽  
Gamma Oscillations ◽  
Theta Activity ◽  
Coherent Oscillation ◽  
Phase Coupling ◽  
Internal Memory ◽  
Complex Interactions ◽  
Theta Frequency ◽  
Memory Representations ◽  
Hippocampal Theta

Hippocampal firing is organized in theta sequences controlled by internal memory processes and by external sensory cues, but how these computations are coordinated is not fully understood. Although theta activity is commonly studied as a unique coherent oscillation, it is the result of complex interactions between different rhythm generators. Here, by separating hippocampal theta activity in three different current generators, we found epochs with variable theta frequency and phase coupling, suggesting flexible interactions between theta generators. We found that epochs of highly synchronized theta rhythmicity preferentially occurred during behavioral tasks requiring coordination between internal memory representations and incoming sensory information. In addition, we found that gamma oscillations were associated with specific theta generators and the strength of theta-gamma coupling predicted the synchronization between theta generators. We propose a mechanism for segregating or integrating hippocampal computations based on the flexible coordination of different theta frameworks to accommodate the cognitive needs.

Sign in / Sign up

Export Citation Format

Share Document