The Search for the Phonological Store: From Loop to Convolution

2008 ◽  
Vol 20 (5) ◽  
pp. 762-778 ◽  
Author(s):  
Bradley R. Buchsbaum ◽  
Mark D'Esposito
Keyword(s):  
Cognitive Psychology ◽  
Short Term Memory ◽  
Functional Neuroimaging ◽  
Temporal Cortex ◽  
Functional Brain Imaging ◽  
Phonological Loop ◽  
Neural Processes ◽  
Phonological Store ◽  
Modern Era ◽  
The Brain

The phonological loop system of Baddeley and colleagues' Working Memory model is a major accomplishment of the modern era of cognitive psychology. It was one of the first information processing models to make an explicit attempt to accommodate both traditional behavioral data and the results of neuropsychological case studies in an integrated theoretical framework. In the early and middle 1990s, the purview of the phonological loop was expanded to include the emerging field of functional brain imaging. The modular and componential structure of the phonological loop seemed to disclose a structure that might well be transcribed, intact, onto the convolutions of the brain. It was the phonological store component, however, with its simple and modular quality, that most appealed to the neuroimaging field as the psychological “box” that might most plausibly be located in the brain. Functional neuroimaging studies initially designated regions in the parietal cortex as constituting the “neural correlate” of the phonological store, whereas later studies pointed to regions in the posterior temporal cortex. In this review, however, we argue the phonological store as a theoretical construct does not precisely correspond to a single, functionally discrete, brain region. Rather, converging evidence from neurology, cognitive psychology, and functional neuroimaging argue for a reconceptualization of phonological short-term memory as emerging from the integrated action of the neural processes that underlie the perception and production of speech.

scholarly journals Short-Term and Procedural Memory for Colours and Inferior Temporal Cortex Activity

1997 ◽  
Vol 10 (2-3) ◽  
pp. 83-92
Author(s):  
E. Castro-Sierra ◽  
E. Paredes-Díaz ◽  
J. A. Lazareff
Keyword(s):  
Short Term Memory ◽  
Temporal Cortex ◽  
Normal Subjects ◽  
Procedural Memory ◽  
Size Perception ◽  
Inferior Temporal Cortex ◽  
Short Term ◽  
Procedural Task ◽  
The Brain ◽  
Normal Controls

Two children (male, 10 years, and female, 13 years one month) with tumours of the inferior temporal (IT) cortex of the brain were studied post-surgically for their abilities to carry out a short-term memory test. This involved: differences in colour, number and shape of small plastic objects; differences in receptacles where these objects should be placed and in ways in which this placement should be done; a procedural task involving differences either in colour or in size of wooden rings employed in the task. Their performances in these tests, and those of patients with tumours of other encephalic areas, were compared with the performances of normal controls. The subjects with IT tumours spent a significantly greater amount of time than normal subjects of their age in carrying out the procedural task involving differences in colour. One of the IT subjects also spent a significantly greater amount of time in the procedural task involving size differences. Other differences in the performances of patients with encephalic tumours and the performances of normal controls were not significant. Results are discussed in relation to findings of colour and size perception and memory localized to the inferior temporal and middle temporal cortices.

scholarly journals Functional neuroimaging as a direct probe of the effects of gonadal steroid hormones on the brain

2002 ◽  
Vol 4 (2) ◽  
pp. 192-195
Keyword(s):  
Steroid Hormones ◽  
Animal Studies ◽  
Functional Neuroimaging ◽  
Functional Brain Imaging ◽  
Neural Function ◽  
Gonadal Steroid Hormones ◽  
Gonadal Steroid ◽  
Neurophysiological Data ◽  
Health And Disease ◽  
The Brain

There is considerable evidence from animal studies dial gonadal steroid hormones modulate neuronal activity and affect behavior. In humans, however, the behavioral and cognitive evidence has not been conclusive, and, until recently, there have been few direct neurophysiological data. Functional brain imaging offers unique opportunities to characterize in humans the effects of gonadal steroid hormones on basic neurobiological parameters, such as neuronal metabolism and neurochemical systems, and to clarify the interactions between these hormones and cognition and mood regulation in health and disease. The most commonly used tools within the considerable armamentarium available for such research and the parameters of neural function that they can access are briefly reviewed here.

History of Functional Brain Imaging

2020 ◽  
Author(s):  
Michael A. Cole ◽  
Christopher N. Sozda ◽  
Mark D'Esposito
Keyword(s):  
Functional Organization ◽  
Functional Neuroimaging ◽  
Empirical Support ◽  
Normal Subjects ◽  
Functional Brain Imaging ◽  
Technological Advances ◽  
The 1960S ◽  
Effective Use ◽  
The 19Th Century ◽  
The Brain

Modern functional neuroimaging techniques can be dated to the 1960s, although humans have been trying to understand the functional organization of the brain for millennia. Precursors of modern techniques were quite crude and date roughly to the 19th century. Rapid technological advances during the end of the 20th century provided researchers with tools capable of measuring hemodynamic activity within the brain, such as changes in blood flow and metabolism, and these techniques quickly became core methodological approaches in the disciplines of cognitive and clinical neuroscience. Notably, clinicians and researchers were significantly aided in their ability to examine diffuse neural networks underlying complex cognitive functions such as working memory, learning, and attention in normal subjects and patient populations. Although the clinical application of functional neuroimaging methodologies have been limited to date, research in this area is rapidly growing and empirical support exists for effective use of techniques such as fMRI and PET, for instance, in presurgical mapping and early detection of Alzheimer’s disease.

scholarly journals Utility of SPECT Functional Neuroimaging of Pain

2021 ◽  
Vol 12 ◽  
Author(s):  
Mohammed Bermo ◽  
Mohammed Saqr ◽  
Hunter Hoffman ◽  
David Patterson ◽  
Sam Sharar ◽  
...  
Keyword(s):  
Brain Imaging ◽  
Functional Neuroimaging ◽  
Brain Activity ◽  
Photon Emission ◽  
Brain Activation ◽  
Brain Perfusion ◽  
Functional Brain Imaging ◽  
Functional Brain ◽  
Clinical Scenarios ◽  
The Brain

Functional neuroimaging modalities vary in spatial and temporal resolution. One major limitation of most functional neuroimaging modalities is that only neural activation taking place inside the scanner can be imaged. This limitation makes functional neuroimaging in many clinical scenarios extremely difficult or impossible. The most commonly used radiopharmaceutical in Single Photon Emission Tomography (SPECT) functional brain imaging is Technetium 99 m-labeled Ethyl Cysteinate Dimer (ECD). ECD is a lipophilic compound with unique pharmacodynamics. It crosses the blood brain barrier and has high first pass extraction by the neurons proportional to regional brain perfusion at the time of injection. It reaches peak activity in the brain 1 min after injection and is then slowly cleared from the brain following a biexponential mode. This allows for a practical imaging window of 1 or 2 h after injection. In other words, it freezes a snapshot of brain perfusion at the time of injection that is kept and can be imaged later. This unique feature allows for designing functional brain imaging studies that do not require the patient to be inside the scanner at the time of brain activation. Functional brain imaging during severe burn wound care is an example that has been extensively studied using this technique. Not only does SPECT allow for imaging of brain activity under extreme pain conditions in clinical settings, but it also allows for imaging of brain activity modulation in response to analgesic maneuvers whether pharmacologic or non-traditional such as using virtual reality analgesia. Together with its utility in extreme situations, SPECTS is also helpful in investigating brain activation under typical pain conditions such as experimental controlled pain and chronic pain syndromes.

What can Functional Neuroimaging Tell the Experimental Psychologist?

2005 ◽  
Vol 58 (2) ◽  
pp. 193-233 ◽  
Author(s):  
Richard Henson
Keyword(s):  
Short Term Memory ◽  
Functional Neuroimaging ◽  
A Priori ◽  
Qualitative Difference ◽  
Imaging Data ◽  
Structure Mapping ◽  
Function Structure ◽  
Experimental Conditions ◽  
Neuroimaging Data ◽  
The Brain

I argue here that functional neuroimaging data—which I restrict to the haemodynamic techniques of fMRI and PET—can inform psychological theorizing, provided one assumes a “systematic” function–structure mapping in the brain. In this case, imaging data simply comprise another dependent variable, along with behavioural data, that can be used to test competing theories. In particular, I distinguish two types of inference: function-to-structure deduction and structure-to-function induction. With the former inference, a qualitatively different pattern of activity over the brain under two experimental conditions implies at least one different function associated with changes in the independent variable. With the second type of inference, activity of the same brain region(s) under two conditions implies a common function, possibly not predicted a priori. I illustrate these inferences with imaging studies of recognition memory, short-term memory, and repetition priming. I then consider in greater detail what is meant by a “systematic” function–structure mapping and argue that, particularly for structure-to-function induction, this entails a one-to-one mapping between functional and structural units, although the structural unit may be a network of interacting regions and care must be taken over the appropriate level of functional/structural abstraction. Nonetheless, the assumption of a systematic function–structure mapping is a “working hypothesis” that, in common with other scientific fields, cannot be proved on independent grounds and is probably best evaluated by the success of the enterprise as a whole. I also consider statistical issues such as the definition of a qualitative difference and methodological issues such as the relationship between imaging and behavioural data. I finish by reviewing various objections to neuroimaging, including neophrenology, functionalism, and equipotentiality, and by observing some criticisms of current practice in the imaging literature.

The Acute Effect of Alcohol on Various Memory Processes

2010 ◽  
Vol 24 (4) ◽  
pp. 249-252 ◽  
Author(s):  
Márk Molnár ◽  
Roland Boha ◽  
Balázs Czigler ◽  
Zsófia Anna Gaál
Keyword(s):  
Low Dose ◽  
Short Term Memory ◽  
Acute Effect ◽  
Long Term Memory ◽  
Term Memory ◽  
Memory Processes ◽  
Different Types ◽  
The Brain ◽  
Legal Consequences

This review surveys relevant and recent data of the pertinent literature regarding the acute effect of alcohol on various kinds of memory processes with special emphasis on working memory. The characteristics of different types of long-term memory (LTM) and short-term memory (STM) processes are summarized with an attempt to relate these to various structures in the brain. LTM is typically impaired by chronic alcohol intake but according to some data a single dose of ethanol may have long lasting effects if administered at a critically important age. The most commonly seen deleterious acute effect of alcohol to STM appears following large doses of ethanol in conditions of “binge drinking” causing the “blackout” phenomenon. However, with the application of various techniques and well-structured behavioral paradigms it is possible to detect, albeit occasionally, subtle changes of cognitive processes even as a result of a low dose of alcohol. These data may be important for the consideration of legal consequences of low-dose ethanol intake in conditions such as driving, etc.

What Has Direct Cortical and Subcortical Electrostimulation Taught Us about Neurolinguistics?

2019 ◽  
pp. 185-211
Author(s):  
Hugues Duffau
Keyword(s):  
White Matter ◽  
Large Scale ◽  
Functional Neuroimaging ◽  
Great Accuracy ◽  
Subcortical White Matter ◽  
Cerebral Lesions ◽  
Physiological Basis ◽  
Postoperative Mri ◽  
The Brain

Investigating the neural and physiological basis of language is one of the most important challenges in neurosciences. Direct electrical stimulation (DES), usually performed in awake patients during surgery for cerebral lesions, is a reliable tool for detecting both cortical and subcortical (white matter and deep grey nuclei) regions crucial for cognitive functions, especially language. DES transiently interacts locally with a small cortical or axonal site, but also nonlocally, as the focal perturbation will disrupt the entire subnetwork sustaining a given function. Thus, in contrast to functional neuroimaging, DES represents a unique opportunity to identify with great accuracy and reproducibility, in vivo in humans, the structures that are actually indispensable to the function, by inducing a transient virtual lesion based on the inhibition of a subcircuit lasting a few seconds. Currently, this is the sole technique that is able to directly investigate the functional role of white matter tracts in humans. Thus, combining transient disturbances elicited by DES with the anatomical data provided by pre- and postoperative MRI enables to achieve reliable anatomo-functional correlations, supporting a network organization of the brain, and leading to the reappraisal of models of language representation. Finally, combining serial peri-operative functional neuroimaging and online intraoperative DES allows the study of mechanisms underlying neuroplasticity. This chapter critically reviews the basic principles of DES, its advantages and limitations, and what DES can reveal about the neural foundations of language, that is, the large-scale distribution of language areas in the brain, their connectivity, and their ability to reorganize.

scholarly journals Perceiving actions before they happen: psychological dimensions scaffold neural action prediction

2020 ◽  
Author(s):  
Mark A Thornton ◽  
Diana I Tamir
Keyword(s):  
Magnetic Resonance Imaging ◽  
Functional Neuroimaging ◽  
Social World ◽  
Action Space ◽  
Action Prediction ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
The Social ◽  
Psychological Dimensions ◽  
The Brain

Abstract The social world buzzes with action. People constantly walk, talk, eat, work, play, snooze and so on. To interact with others successfully, we need to both understand their current actions and predict their future actions. Here we used functional neuroimaging to test the hypothesis that people do both at the same time: when the brain perceives an action, it simultaneously encodes likely future actions. Specifically, we hypothesized that the brain represents perceived actions using a map that encodes which actions will occur next: the six-dimensional Abstraction, Creation, Tradition, Food(-relevance), Animacy and Spiritualism Taxonomy (ACT-FAST) action space. Within this space, the closer two actions are, the more likely they are to precede or follow each other. To test this hypothesis, participants watched a video featuring naturalistic sequences of actions while undergoing functional magnetic resonance imaging (fMRI) scanning. We first use a decoding model to demonstrate that the brain uses ACT-FAST to represent current actions. We then successfully predicted as-yet unseen actions, up to three actions into the future, based on their proximity to the current action’s coordinates in ACT-FAST space. This finding suggests that the brain represents actions using a six-dimensional action space that gives people an automatic glimpse of future actions.

A Theoretical Basis for Emergent Pattern Discrimination in Neural Systems Through Slow Feature Extraction

2010 ◽  
Vol 22 (12) ◽  
pp. 2979-3035 ◽  
Author(s):  
Stefan Klampfl ◽  
Wolfgang Maass
Keyword(s):  
Feature Extraction ◽  
Theoretical Basis ◽  
Learning Algorithm ◽  
Temporal Cortex ◽  
Pattern Discrimination ◽  
Stimulus Onset ◽  
Inferior Temporal Cortex ◽  
Linear Discriminant ◽  
Discrimination Capability ◽  
The Brain

Neurons in the brain are able to detect and discriminate salient spatiotemporal patterns in the firing activity of presynaptic neurons. It is open how they can learn to achieve this, especially without the help of a supervisor. We show that a well-known unsupervised learning algorithm for linear neurons, slow feature analysis (SFA), is able to acquire the discrimination capability of one of the best algorithms for supervised linear discrimination learning, the Fisher linear discriminant (FLD), given suitable input statistics. We demonstrate the power of this principle by showing that it enables readout neurons from simulated cortical microcircuits to learn without any supervision to discriminate between spoken digits and to detect repeated firing patterns that are embedded into a stream of noise spike trains with the same firing statistics. Both these computer simulations and our theoretical analysis show that slow feature extraction enables neurons to extract and collect information that is spread out over a trajectory of firing states that lasts several hundred ms. In addition, it enables neurons to learn without supervision to keep track of time (relative to a stimulus onset, or the initiation of a motor response). Hence, these results elucidate how the brain could compute with trajectories of firing states rather than only with fixed point attractors. It also provides a theoretical basis for understanding recent experimental results on the emergence of view- and position-invariant classification of visual objects in inferior temporal cortex.

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