Different Phases Of Learning Research Articles

Learning an operant conditioning task differentially induces gliogenesis in the medial prefrontal cortex and neurogenesis in the hippocampus.

Circuit modification associated with learning and memory involves multiple events, including the addition and remotion of newborn cells trough adulthood. Adult neurogenesis and gliogenesis were mainly described in models of voluntary exercise, enriched environments, spatial learning and memory task; nevertheless, it is unknown whether it is a common mechanism among different learning paradigms, like reward dependent tasks. Therefore, we evaluated cell proliferation, neurogenesis, astrogliogenesis, survival and neuronal maturation in the medial prefrontal cortex (mPFC) and the hippocampus (HIPP) during learning an operant conditioning task. This was performed by using endogenous markers of cell proliferation, and a bromodeoxiuridine (BrdU) injection schedule in two different phases of learning. Learning an operant conditioning is divided in two phases: a first phase when animals were considered incompletely trained (IT, animals that were learning the task) when they performed between 50% and 65% of the responses, and a second phase when animals were considered trained (Tr, animals that completely learned the task) when they reached 100% of the responses with a latency time lower than 5 seconds. We found that learning an operant conditioning task promoted cell proliferation in both phases of learning in the mPFC and HIPP. Additionally, the results presented showed that astrogliogenesis was induced in the medial prefrontal cortex (mPFC) in both phases, however, the first phase promoted survival of these new born astrocytes. On the other hand, an increased number of new born immature neurons was observed in the HIPP only in the first phase of learning, whereas, decreased values were observed in the second phase. Finally, we found that neuronal maturation was induced only during the first phase. This study shows for the first time that learning a reward-dependent task, like the operant conditioning, promotes neurogenesis, astrogliogenesis, survival and neuronal maturation depending on the learning phase in the mPFC-HIPP circuit.

Brain areas contributing to different phases of visual spatial learning in mice and humans

Event Abstract Back to Event Brain areas contributing to different phases of visual spatial learning in mice and humans Ilse Gantois1*, Annelies Laeremans2, Daniel Woolley3, Lut Arckens2, Nici Wenderoth3 and Rudi D Hooge1 1 K.U, Laboratory of Biological Psychology, Belgium 2 KU, Laboratory of Neuroplasticity and Neuroproteomics, Belgium 3 KU, Laboratory of Movement Control and Neuroplasticity, Belgium It is well established that the striatum and hippocampus are critically involved in visuo-spatial learning processes. There is evidence that these structures contribute at different phases of learning. Comparing brain activation in a similar spatial learning task between mice and humans will provide more insight into the specific differential and time dependent contributions of striatum and hippocampus. Additionally, we will further assess if there is also overlap in the function of these brain areas. Mice were trained in the Morris water maze task for either 3 days (early learning phase group) or 4 weeks (late learning phase group). Neuronal activity at different phases of spatial learning was determined by a comparison of expression levels of the immediate early genes Arc, Homer1a and Zif268 in hippocampus and striatum between different mouse groups. Data show higher activity of the hippocampus during the early learning phase compared to the late phase, as expected. Upregulation of the ventrolateral striatum was observed during the early learning phase, while activity was higher in dorsal striatum during the late learning phase. We developed a virtual Morris water maze to measure human brain activation during different phases of learning. The task was designed to ensure that specific learning processes observed in both species are comparable. First fMRI data show increased activation of striatum in the late learning phase when compared to the early learning phase of the task (specifically during the initial orientation period of the trial). Using the human virtual Morris water maze allows us to cross-validate learning related plasticity between mouse and human research. Conference: 41st European Brain and Behaviour Society Meeting, Rhodes Island, Greece, 13 Sep - 18 Sep, 2009. Presentation Type: Poster Presentation Topic: Poster presentations Citation: Gantois I, Laeremans A, Woolley D, Arckens L, Wenderoth N and D Hooge R (2009). Brain areas contributing to different phases of visual spatial learning in mice and humans. Conference Abstract: 41st European Brain and Behaviour Society Meeting. doi: 10.3389/conf.neuro.08.2009.09.153 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 09 Jun 2009; Published Online: 09 Jun 2009. * Correspondence: Ilse Gantois, K.U, Laboratory of Biological Psychology, Leuven, Belgium, ilse.gantois@psy.kuleuven.be Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Ilse Gantois Annelies Laeremans Daniel Woolley Lut Arckens Nici Wenderoth Rudi D Hooge Google Ilse Gantois Annelies Laeremans Daniel Woolley Lut Arckens Nici Wenderoth Rudi D Hooge Google Scholar Ilse Gantois Annelies Laeremans Daniel Woolley Lut Arckens Nici Wenderoth Rudi D Hooge PubMed Ilse Gantois Annelies Laeremans Daniel Woolley Lut Arckens Nici Wenderoth Rudi D Hooge Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Creating and Sustaining Online Learning Communities: Designing for Transformative Learning

Learning can be profoundly and personally transformative when it occurs within a community. Creating knowledge in learning communities can facilitate innovative solutions to increasingly complex problems in today's knowledge society. Designing the right environment to create online communities is a complex task that has implications for designers, facilitators and participants. The aim is to create a community that welcomes and engages in constructive controversy, prompting learners to view their practice in an entirely new way. Three significant environmental factors that will enable the creation of a supportive community in which transformative learning can occur include social presence, authentic learning and interdependency. These are intricately linked and take on different levels of importance in different phases of learning and community development. Getting the balance right and being aware of when to emphasise a particular environmental factor is necessary to establish a community that can effectively engage in constructive controversy leading to personal transformation.

Creating and Sustaining Online Learning Communities: Designing Environments for Transformative Learning

Learning can be profoundly and personally transformative when it occurs within a community. Creating knowledge in learning communities can facilitate innovative solutions to increasingly complex problems in today's knowledge society. Designing the right environment to sustain online communities is a complex task that has implications for designers, facilitators and participants. When the community is able to function effectively, learning for the individual learner can result in a deeply transformative experience where they are able to view their practice in an entirely new way. Two significant environmental factors that will sustain the learning community through constructive controversy and thereby nurture individuals through the transformative learning process are critical discourse and parallel leadership. These factors are intricately linked and take on different levels of importance in different phases of learning and community development. Establishing a community that can sustain itself through the constructive controversy of learning is essential if the community is to effectively engage in knowledge creation and personal transformation through learning.

The Cultural Transmission of Great Basin Projectile-Point Technology I: An Experimental Simulation

A Darwinian evolutionary approach to archaeology naturally leads to a focus on cultural transmission. Theoretical models of cultural evolution indicate that individual-level details of cultural transmission can have specific and significant population-level effects, implying that differences in transmission may be detectable in the archaeological record. Here we present an experimental simulation of the cultural transmission of prehistoric projectile-point technology, simulating the two transmission modes-indirect bias and guided variation-that Bettinger and Eerkens (1999) suggested were responsible for differences in Nevada and California point-attribute correlations. Groups of participants designed “virtual projectile points” and tested them in “virtual hunting environments,” with different phases of learning simulating, alternately, indirectly biased cultural transmission and independent individual learning. As predicted, periods of cultural transmission were associated with significantly stronger attribute correlations than were periods of individual learning. We also found that participants who could engage in indirectly biased horizontal cultural transmission outperformed individual-learning controls, especially when individual learning was costly and the selective environment was multimodal. The study demonstrates that experimental simulations of cultural transmission, used alongside archaeological data, mathematical models and computer simulations, constitute a useful tool for studying cultural change.

Polysialylated Neural Cell Adhesion Molecule Is Involved in Induction of Long-Term Potentiation and Memory Acquisition and Consolidation in a Fear-Conditioning Paradigm

Polysialic acid (PSA) regulates functions of the neural cell adhesion molecule (NCAM) during development and in neuroplasticity in the adult; the underlying mechanisms at different phases of learning and memory consolidation are, however, unknown. To investigate the contributions of PSA versus the extracellular domain of the NCAM glycoprotein backbone to synaptic plasticity, we applied NCAM, PSA-NCAM, and PSA to acute slices of the hippocampal CA1 region of NCAM-deficient mice and measured their effects on long-term potentiation (LTP). Remarkably, only PSA and PSA-NCAM, but not NCAM restored normal LTP. Application of these molecules to the dorsal hippocampus of wild-type mice showed that PSA-NCAM and PSA, but not NCAM, injected before fear conditioning, impaired formation of hippocampus-dependent contextual memory. Consolidation of contextual memory was affected by PSA-NCAM only when injected during its late, but not early phases. None of the tested compounds disturbed extrahippocampal-cued memory. Mice lacking the polysialyltransferase (ST8SialV/PST) responsible for attachment of PSA to NCAM in adulthood showed a mild deficit only in hippocampal contextual learning, when compared with NCAM-deficient mice that were disturbed in both contextual and cued memories. Contextual and tone memory in NCAM-deficient mice could be partially restored by injection of PSA-NCAM, but not of NCAM, into the hippocampus, suggesting that the impact of PSA-NCAM in synaptic plasticity and learning is not mediated by modulation of NCAM-NCAM homophilic interactions. In conclusion, our data support the view that polysialylated NCAM is involved in both formation and late consolidation of contextual memory.

Hemodynamic responses of the amygdala, the orbitofrontal cortex and the visual cortex during a fear conditioning paradigm

Functional magnetic resonance imaging (fMRI) studies consistently demonstrate an enhanced activation of the visual cortex in reaction to emotionally salient visual stimuli. This increase of activation is probably modulated by top-down processes, that are initiated in emotion processing structures, specifically the amygdala and the orbitofrontal cortex. In the present fMRI study, a differential fear conditioning paradigm was applied to investigate this assumed modulation. Hemodynamic responses towards a neutral visual stimulus (CS+) predicting an electrical stimulation (UCS) were compared with responses towards a neutral and unpaired stimulus (CS−). Thereby, particularly the time courses of neural responses were considered. Skin conductance measures were concurrently recorded. Our results show that the differentiation between CS+ and CS− within the amygdala and the extended visual cortex was accomplished during a late acquisition phase. In the orbitofrontal cortex the differentiation occurred at an earlier stage and was then sustained throughout acquisition. It is suggested that these altering activation patterns are reflecting different phases of learning, integrating the analyzed regions to varying degrees. Additionally, the results indicate that statistical analyses comprising a temporal variation of hemodynamic responses are more likely to detect amygdala activation.

Hippocampal CA3-region is crucial for acquisition and memory consolidation in Morris water maze task in mice

This experiment investigated the involvement of the dorsal hippocampal CA3-region in the different phases of learning and memory in spatial and non-spatial tasks. To do so, we temporarily inactivated the CA3-subfield by a focal injection of diethyldithiocarbamate (DDC) which chelates most of the heavy metals present in this region. The effects of temporary inactivation of the CA3-region were examined in an associative task, the Morris water maze (MWM). To study the different phase of memory we used a new behavioural massed-procedure founded on four massed training sessions in the spatial and the non-spatial (cue) version of this task. In the spatial version, we showed that a bilateral injection of DDC into the CA3-region impairs the acquisition but not the recall of spatial information. The main result of this study is that the same injection performed immediately after the training session also perturbed memory consolidation. In the cue version of the MWM, we found no difference between the DDC-injected mice and their controls in acquisition or memory consolidation of non-spatial information. These results suggest that the hippocampal CA3-region is essential for spatial memory processes and specifically in memory consolidation of spatial information.

Involvement of the hippocampal CA3-region in acquisition and in memory consolidation of spatial but not in object information in mice

This study investigates the implication of the hippocampal CA3-region in the different phases of learning and memory in spatial and non-spatial tasks. For that purpose, we performed focal injections of diethyldithiocarbamate (DDC) into the CA3-region of the dorsal hippocampus. The DDC chelates most of the heavy metals in the brain which blocks selectively and reversibly the synapses containing heavy metals, i.e., the mossy fibres synaptic buttons and synapses of the dendrites of pyramidal cells. The effects of temporal inactivation of the CA3-region was examined in a non-associative task, the spatial open-field, designed to estimate the ability of mice to react to spatial changes, and in the object recognition task, designed to estimate the ability of mice to identify a familiar object. The results show that DDC induced a specific impairment on learning and memory consolidation in the spatial open-field but had no effect on recall in this task. In the object recognition task, DDC did not induce any impairment in the different phases of learning and memory. These data demonstrate that the hippocampal CA3-region is specifically implicated in spatial information processing and seems to be involved not only in acquisition but also in consolidation of spatial information.

Imaging Brain Plasticity during Motor Skill Learning

The search for the neural substrates mediating the incremental acquisition of skilled motor behaviors has been the focus of a large body of animal and human studies in the past decade. Much less is known, however, with regard to the dynamic neural changes that occur in the motor system during the different phases of learning. In this paper, we review recent findings, mainly from our own work using fMRI, which suggest that: (i) the learning of sequential finger movements produces a slowly evolving reorganization within primary motor cortex (M1) over the course of weeks and (ii) this change in M1 follows more dynamic, rapid changes in the cerebellum, striatum, and other motor-related cortical areas over the course of days. We also briefly review neurophysiological and psychophysical evidence for the consolidation of motor skills, and we propose a working hypothesis of its underlying neural substrate in motor sequence learning.

Dynamic Cortical and Subcortical Networks in Learning and Delayed Recall of Timed Motor Sequences

We used positron emission tomography to examine learning and retention of timed motor sequences. Subjects were scanned during learning (LRN) and baseline (ISO) on 3 d: day 1, after 5 d of practice (day 5) and after a 4 week delay (recall). Blood flow was compared across days of learning and between the LRN and ISO conditions. Overall, significant changes in activity were seen across days for the LRN condition, but not the ISO baseline. Day 1 results revealed extensive activation in the cerebellar cortex, particularly lobules III/IV and VI. Day 5 results showed increased activity in the basal ganglia (BG) and frontal lobe, with no significant cerebellar activity. At recall, significantly greater activity was seen in M1, premotor, and parietal cortex. Blood flow in the cerebellum decreased significantly between day 1 and recall. These results reveal a dynamic network of motor structures that are differentially active during different phases of learning and delayed recall. For the first time our findings show that recall of motor sequences in humans is mediated by a predominantly cortical network. Based on these results, we suggest that during early learning cerebellar mechanisms are involved in adjusting movement kinematics according to sensory input to produce accurate motor output. Thereafter, the cerebellar mechanisms required for early learning are no longer called into play. During late learning, the BG may be involved in automatization. At delayed recall, movement parameters appear to be encoded in a distributed representation mediated by M1, premotor, and parietal cortex.

SR 141716A prevents Δ 9-tetrahydrocannabinol-induced spatial learning deficit in a Morris-type water maze in mice

This study reports a series of spatial discrimination procedures in a Morris-type maze to investigate the effects of Δ 9-tetrahydrocannabinol (Δ 9-THC) on different phases of learning and memory in mice. Adult male mice were given training trails to find the submerged platform at a fixed location in the water maze adapted for mice. In additional experiments, mice were trained with the repeated acquisition procedure to test the working memory. Results indicate that Δ 9-THC (8 mg/kg ip) 30 min pretest impaired specifically the acquisition of spatial learning and the performance of mice in the working memory task, while consolidation and retrieval of a previously learned task were not affected. There was no evidence of motoric difficulty, as the number of quadrant line crossings was not decreased and no visible sign of sensorimotor disturbance was observed during swimming. Pretreatment with SR 141716A (1 mg/kg ip), a CB1 cannabinoid receptor antagonist, significantly prevented the learning deficits in the water maze. These findings show that Δ 9-THC impairs spatial discrimination learning in a selective way in the water maze in mice and that these deficits may be mediated by cannabinoid receptors.

NMDA receptor antagonist AP5 and nitric oxide synthase inhibitor 7-NI affect different phases of learning and memory in goldfish

The present study investigated the amnestic effects of N-methyl- d-aspartate (NMDA) receptor antagonist AP5 and nitric oxide (NO) synthase inhibitor 7-NI in avoidance conditioning in goldfish. The results showed that both AP5 and 7-NI, without impairing performance processes, produced anterograde amnesia when given before training. Furthermore, 7-NI produced retrograde amnesia when given immediately following training while AP5 did not. Thus, AP5 and 7-NI affected different phases of learning and memory.