scholarly journals Revisiting the Role of the Medial Temporal Lobe in Motor Learning

2021 ◽  
pp. 1-18
Author(s):  
Samuel D. McDougle ◽  
Sarah A. Wilterson ◽  
Nicholas B. Turk-Browne ◽  
Jordan A. Taylor
Keyword(s):  
Motor Learning ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Declarative Memory ◽  
Action Selection ◽  
Memory Systems ◽  
Memory Processes ◽  
Multiple Memory Systems ◽  
Selection Strategies ◽  
Arbitrary Action

Abstract Classic taxonomies of memory distinguish explicit and implicit memory systems, placing motor skills squarely in the latter branch. This assertion is in part a consequence of foundational discoveries showing significant motor learning in amnesics. Those findings suggest that declarative memory processes in the medial temporal lobe (MTL) do not contribute to motor learning. Here, we revisit this issue, testing an individual (L. S. J.) with severe MTL damage on four motor learning tasks and comparing her performance to age-matched controls. Consistent with previous findings in amnesics, we observed that L. S. J. could improve motor performance despite having significantly impaired declarative memory. However, she tended to perform poorly relative to age-matched controls, with deficits apparently related to flexible action selection. Further supporting an action selection deficit, L. S. J. fully failed to learn a task that required the acquisition of arbitrary action–outcome associations. We thus propose a modest revision to the classic taxonomic model: Although MTL-dependent memory processes are not necessary for some motor learning to occur, they play a significant role in the acquisition, implementation, and retrieval of action selection strategies. These findings have implications for our understanding of the neural correlates of motor learning, the psychological mechanisms of skill, and the theory of multiple memory systems.

scholarly journals Against memory systems

2002 ◽  
Vol 357 (1424) ◽  
pp. 1111-1121 ◽  
Author(s):  
David Gaffan
Keyword(s):  
Temporal Lobe ◽  
Cortical Neurons ◽  
Medial Temporal Lobe ◽  
Temporal Cortex ◽  
Memory Systems ◽  
Memory System ◽  
Memory Processing ◽  
Multiple Memory Systems ◽  
Cortical Areas ◽  
Severe Impairment

The medial temporal lobe is indispensable for normal memory processing in both human and non–human primates, as is shown by the fact that large lesions in it produce a severe impairment in the acquisition of new memories. The widely accepted inference from this observation is that the medial temporal cortex, including the hippocampal, entorhinal and perirhinal cortex, contains a memory system or multiple memory systems, which are specialized for the acquisition and storage of memories. Nevertheless, there are some strong arguments against this idea: medial temporal lesions produce amnesia by disconnecting the entire temporal cortex from neuromodulatory afferents arising in the brainstem and basal forebrain, not by removing cortex; the temporal cortex is essential for perception as well as for memory; and response properties of temporal cortical neurons make it impossible that some kinds of memory trace could be stored in the temporal lobe. All cortex is plastic, and it is possible that the same rules of plasticity apply to all cortical areas; therefore, memory traces are stored in widespread cortical areas rather than in a specialized memory system restricted to the temporal lobe. Among these areas, the prefrontal cortex has an important role in learning and memory, but is best understood as an area with no specialization of function.

Remembering

Daedalus ◽  
2015 ◽  
Vol 144 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Larry R. Squire ◽  
John T. Wixted
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Human Memory ◽  
Memory Systems ◽  
Consolidation Process ◽  
Multiple Memory Systems ◽  
Memory Work ◽  
Major Development ◽  
The Brain

A major development in understanding the structure and organization of memory was the identification of the medial temporal lobe memory system as one of the brain systems that support memory. Work on this topic began in the 1950s with the study of the noted amnesic patient H.M. and culminated in studies of an animal model of human memory impairment in the nonhuman primate. These discoveries opened new frontiers of research concerned with the functional specialization of structures within the medial temporal lobe, the existence of multiple memory systems, the process of memory consolidation, and the role of neural replay and sleep in the consolidation process. This work also led to new insights about how and where memories are ultimately stored in the brain. All of this research has improved our understanding of how memory is affected by normal aging and why it is so profoundly impaired by the pathological processes associated with dementia.

scholarly journals The Contribution of the Human Medial Temporal Lobe to Perception: Bridging the Gap between Animal and Human Studies

2005 ◽  
Vol 58 (3-4b) ◽  
pp. 300-325 ◽  
Author(s):  
Andy C. H. Lee ◽  
Morgan D. Barense ◽  
Kim S. Graham
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Nonhuman Primates ◽  
Declarative Memory ◽  
Object Perception ◽  
Perirhinal Cortex ◽  
Higher Order ◽  
Human Studies ◽  
Memory Processes ◽  
Current Article

The medial temporal lobe (MTL) has been considered traditionally to subserve declarative memory processes only. Recent studies in nonhuman primates suggest, however, that the MTL may also be critical to higher order perceptual processes, with the hippocampus and perirhinal cortex being involved in scene and object perception, respectively. The current article reviews the human neuropsychological literature to determine whether there is any evidence to suggest that these same views may apply to the human MTL. Although the majority of existing studies report intact perception following MTL damage in human amnesics, there have been recent studies that suggest that when scene and object perception are assessed systematically, signifi-cant impairments in perception become apparent. These findings have important implications for current mnemonic theories of human MTL function and our understanding of human amnesia as a result of MTL lesions.

Multiple Memory Systems and Their Support of Language

2014 ◽  
Vol 24 (2) ◽  
pp. 64-73 ◽  
Author(s):  
Jake Kurczek ◽  
Natalie Vanderveen ◽  
Melissa C. Duff
Keyword(s):  
Memory Impairment ◽  
Language Use ◽  
Declarative Memory ◽  
Memory Systems ◽  
Memory And Learning ◽  
Multiple Memory Systems ◽  
History Of Research ◽  
Language And Communication ◽  
History Of ◽  
The Brain

There is a long history of research linking the various forms of memory to different aspects of language. Clinically, we see this memory-language connection in the prevalence of language and communication deficits in populations that have concomitant impairments in memory and learning. In this article, we provide an overview of how the demands of language use and processing are supported by multiple memory systems in the brain, including working memory, declarative memory and nondeclarative memory, and how disruptions in different forms of memory may affect language. While not an exhaustive review of the literature, special attention is paid to populations who speech-language pathologists (SLPs) routinely serve. The goal of this review is to provide a resource for clinicians working with clients with disorders in memory and learning in helping to understand and anticipate the range of disruptions in language and communication that can arise as a consequence of memory impairment. We also hope this is a catalyst for more research on the contribution of multiple memory systems to language and communication.

Individual Sequence Representations in the Medial Temporal Lobe

2013 ◽  
Vol 25 (7) ◽  
pp. 1111-1121 ◽  
Author(s):  
Kristjan Kalm ◽  
Matthew H. Davis ◽  
Dennis Norris
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Memory Systems ◽  
Long Term Memory ◽  
Specific Sequence ◽  
Level Of Activity ◽  
Serial Recall Task ◽  
Letter Names ◽  
Multivariate Pattern

Much of what we need to remember consists of sequences of stimuli, experiences, or events. Repeated presentation of a specific sequence establishes a more stable long-term memory, as shown by increased recall accuracy over successive trials of an STM task. Here we used fMRI to study the neural mechanisms that underlie sequence learning in the auditory–verbal domain. Specifically, we track the emergence of neural representations of sequences over the course of learning using multivariate pattern analysis. For this purpose, we use a serial recall task, in which participants have to recall overlapping sequences of letter names, with some of those sequences being repeated and hence learned over the course of the experiment. We show that voxels in the hippocampus come to encode the identity of specific repeated sequences although the letter names were common to all sequences in the experiment. These changes could have not been caused by changes in overall level of activity or to fMRI signal-to-noise ratios. Hence, the present results go beyond conventional univariate fMRI methods in showing a critical contribution of medial-temporal lobe memory systems to establishing long-term representations of verbal sequences.

scholarly journals Differences in Mnemonic Processing by Neurons in the Human Hippocampus and Parahippocampal Regions

2006 ◽  
Vol 18 (10) ◽  
pp. 1654-1662 ◽  
Author(s):  
Indre V. Viskontas ◽  
Barbara J. Knowlton ◽  
Peter N. Steinmetz ◽  
Itzhak Fried
Keyword(s):  
Recognition Memory ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Computational Models ◽  
Systems Approach ◽  
Declarative Memory ◽  
Neuronal Firing ◽  
Psychological Review ◽  
Firing Patterns ◽  
Human Hippocampus

Different structures within the medial-temporal lobe likely make distinct contributions to declarative memory. In particular, several current psychological and computational models of memory predict that the hippocampus and parahippocampal regions play different roles in the formation and retrieval of declarative memories [e.g., Norman, K. A., & O'Reilly, R. C. Modeling hippocampal and neocortical contributions to recognition memory: A complementary-learning systems approach. Psychological Review, 110, 611–646, 2003]. Here, we examined the neuronal firing patterns in these two regions during recognition memory. Recording directly from neurons in humans, we find that cells in both regions respond to novel stimuli with an increase in firing (excitation). However, already on the second presentation of a stimulus, neurons in these regions show very different firing patterns. In the parahippocampal region there is dramatic decrease in the number of cells responding to the stimuli, whereas in the hippocampus there is recruitment of a large subset of neurons showing inhibitory (decrease from baseline firing) responses. These results suggest that inhibition is a mechanism used by cells in the human hippocampus to support sparse coding in mnemonic processing. The findings also provide further evidence for the division of labor in the medial-temporal lobe with respect to declarative memory processes.

Multiple Memory Systems: Evidence from Stroke

1987 ◽  
Vol 64 (2) ◽  
pp. 571-577 ◽  
Author(s):  
Laura Cushman ◽  
Bruce Caplan
Keyword(s):  
Declarative Memory ◽  
Verbal Learning ◽  
Memory Systems ◽  
Procedural Learning ◽  
Maze Task ◽  
Learning Abilities ◽  
Multiple Memory Systems ◽  
Mirror Tracing ◽  
Improved Performance ◽  
Selective Preservation

In this report, we describe the “fractionation of memory systems” in a 62-yr.-old woman following a left anterior stroke. Despite the presence of a significant, persistent declarative memory (verbal learning) deficit, this patient exhibited relatively intact procedural learning. The latter was manifested over a 4-day period by improved performance on a maze task executed under “mirror-tracing” conditions. By the final set of trials, the patient's performance approximated that of a normal control subject with respect to speed, although not errors. The selective preservation of particular learning abilities in brain-damaged patients has implications for rehabilitative interventions.

scholarly journals Age-related Alterations in Simple Declarative Memory and the Effect of Negative Stimulus Valence

2009 ◽  
Vol 21 (10) ◽  
pp. 1920-1933 ◽  
Author(s):  
Vishnu P. Murty ◽  
Fabio Sambataro ◽  
Saumitra Das ◽  
Hao-Yang Tan ◽  
Joseph H. Callicott ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Neural Activity ◽  
Medial Temporal Lobe ◽  
Declarative Memory ◽  
Recognition Performance ◽  
Negative Stimulus ◽  
Main Effect ◽  
Stimulus Valence ◽  
Effect Of Age ◽  
Encoding And Retrieval

Healthy aging has been shown to modulate the neural circuitry underlying simple declarative memory; however, the functional impact of negative stimulus valence on these changes has not been fully investigated. Using BOLD fMRI, we explored the effects of aging on behavioral performance, neural activity, and functional coupling during the encoding and retrieval of novel aversive and neutral scenes. Behaviorally, there was a main effect of valence with better recognition performance for aversive greater than neutral stimuli in both age groups. There was also a main effect of age with better recognition performance in younger participants compared to older participants. At the imaging level, there was a main effect of valence with increased activity in the medial-temporal lobe (amygdala and hippocampus) during both encoding and retrieval of aversive relative to neutral stimuli. There was also a main effect of age with older participants showing decreased engagement of medial-temporal lobe structures and increased engagement of prefrontal structures during both encoding and retrieval sessions. Interestingly, older participants presented with relatively decreased amygdalar–hippocampal coupling and increased amygdalar–prefrontal coupling when compared to younger participants. Furthermore, older participants showed increased activation in prefrontal cortices and decreased activation in the amygdala when contrasting the retrieval of aversive and neutral scenes. These results suggest that although normal aging is associated with a decline in declarative memory with alterations in the neural activity and connectivity of brain regions underlying simple declarative memory, memory for aversive stimuli is relatively better preserved than for neutral stimuli, possibly through greater compensatory prefrontal cortical activity.

Sign in / Sign up

Export Citation Format

Share Document