scholarly journals The Bayesian-Laplacian Brain

2016 ◽  
Author(s):  
Semir Zeki ◽  
Oliver Y. Chén
Keyword(s):  
The Other ◽  
Limited Capacity ◽  
The Brain ◽  
Do So

AbstractWe outline what we believe could be an improvement in future discussions of the brain acting as a Bayesian-Laplacian system. We do so by distinguishing between two broad classes of priors on which the brain’s inferential systems operate: in one category are biological priors (β priors) and in the other artifactual ones (α priors). We argue thatβ priors, of which colour categories and faces are good examples, are inherited or acquired very rapidly after birth, are highly or relatively resistant to change through experience, and are common to all humans. The consequence is that the probability of posteriors generated fromβ priorshaving universal assent and agreement is high. By contrast, αpriors, of which man-made objects are examples, are acquired post-natally and modified at various stages throughout post-natal life; they are much more accommodating of, and hospitable to, new experiences. Consequently, posteriors generated from them are less likely to find universal assent. Taken together, in addition to the more limited capacity of experiment and experience to alter theβ priorscompared toα priors, another cardinal distinction between the two is that the probability of posteriors generated fromβ priorshaving universal agreement is greater than that forα priors. The two categories are not, however, always totally distinct and can merge into one another to varying extents, resulting in posteriors that draw upon both categories.

MICROCHEMICAL ASSAYS OF GLUCOSE AND GLUCOSE-6-PHOSPHATE IN MAMMALIAN PANCREATIC β-CELLS

1968 ◽  
Vol 59 (3) ◽  
pp. 479-486 ◽  
Author(s):  
Lars-Ake Idahl ◽  
Bo Hellman
Keyword(s):  
Glucose Level ◽  
Exocrine Pancreas ◽  
The Other ◽  
Wide Concentration Range ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Enzymatic Cycling ◽  
Glucose Diffusion ◽  
Significant Barrier ◽  
The Brain

ABSTRACT The combination of enzymatic cycling and fluorometry was used for measuring glucose and glucose-6-phosphate in pancreatic β-cells from obese-hyperglycaemic mice. The glucose level of the β-cells corresponded to that of serum over a wide concentration range. In the exocrine pancreas, on the other hand, a significant barrier to glucose diffusion across the cell membranes was demonstrated. During 5 min of ischaemia, the glucose level remained practically unchanged in the β-cells while it increased in the liver and decreased in the brain. The observation that the pancreatic β-cells are characterized by a relatively low ratio of glucose-6-phosphate to glucose may be attributed to the presence of a specific glucose-6-phosphatase.

Challenging Gender Hierarchies in Narratives of the Nation: Representations of Women in Zintgraff and the Battle of Mankon and Hard Choice

Imbizo ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Naomi Epongse Nkealah ◽  
Olutoba Gboyega Oluwasuji
Keyword(s):  
The Other ◽  
Literary Texts ◽  
Gender Differentiation ◽  
Hard Choice ◽  
Other Hand ◽  
Gender Hierarchies ◽  
The Face ◽  
The One ◽  
Representations Of Women ◽  
Do So

Ideas of nationalisms as masculine projects dominate literary texts by African male writers. The texts mirror the ways in which gender differentiation sanctions nationalist discourses and in turn how nationalist discourses reinforce gender hierarchies. This article draws on theoretical insights from the work of Anne McClintock and Elleke Boehmer to analyse two plays: Zintgraff and the Battle of Mankon by Bole Butake and Gilbert Doho and Hard Choice by Sunnie Ododo. The article argues that women are represented in these two plays as having an ambiguous relationship to nationalism. On the one hand, women are seen actively changing the face of politics in their societies, but on the other hand, the means by which they do so reduces them to stereotypes of their gender.

Neural and Environmental Modulation of Motivation

2018 ◽  
Author(s):  
Thomas Douglas
Keyword(s):  
Environmental Influence ◽  
Environmental Intervention ◽  
Argument Proceeds ◽  
The Brain ◽  
Moral Difference ◽  
Do So

Interventions that modify a person’s motivations through chemically or physically influencing the brain seem morally objectionable, at least when they are performed nonconsensually. This chapter raises a puzzle for attempts to explain their objectionability. It first seeks to show that the objectionability of such interventions must be explained at least in part by reference to the sort of mental interference that they involve. It then argues that it is difficult to furnish an explanation of this sort. The difficulty is that these interventions seem no more objectionable, in terms of the kind of mental interference that they involve, than certain forms of environmental influence that many would regard as morally innocuous. The argument proceeds by comparing a particular neurointervention with a comparable environmental intervention. The author argues, first, that the two dominant explanations for the objectionability of the neurointervention apply equally to the environmental intervention, and second, that the descriptive difference between the environmental intervention and the neurointervention that most plausibly grounds the putative moral difference in fact fails to do so. The author concludes by presenting a trilemma that falls out of the argument.

The Dioptrique

2017 ◽  
Author(s):  
Walter Ott
Keyword(s):  
Sensory Experience ◽  
The Other ◽  
Brain Image ◽  
Brain Motion ◽  
Natural Geometry ◽  
The Common ◽  
The Brain

Descartes’s treatment of perception in the Optics, though published before the Meditations, contains a distinct account of sensory experience. The end of the chapter suggests some reasons for this oddity, but that the two accounts are distinct is difficult to deny. Descartes in the present work topples the brain image from its throne. In its place, we have two mechanisms, one purely causal, the other inferential. Where the proper sensibles are concerned, the ordination of nature suffices to explain why a given sensation is triggered on the occasion of a given brain motion. The same is true with regard to the common sensibles. But on top of this purely causal story, Descartes re-introduces his doctrine of natural geometry.

Euthyphro, Apology, and Crito

2019 ◽  
pp. 117-140
Author(s):  
Hugh H. Benson
Keyword(s):  
The Other ◽  
Other Hand ◽  
Virtuous Life ◽  
The One ◽  
Do So

This chapter presents a reading of Plato’s Euthyphro, Apology, and Crito. These dialogues, in which Plato depicts the weeks leading up to Socrates’s last day, are replete with various philosophical explorations. Among those explorations is the question of how to live our lives. On the one hand, Socrates is clear and straightforward. We should live the examined life—making logoi and examining ourselves and others in order to determine whether we are as wise as we think we are, and we should live the virtuous life. This is how Socrates lives his life. On the other hand, the examined life undercuts, or at least should undercut, the confidence with which he seeks to live the virtuous life. It may help bring some stability to the general principles by which he lives his life, but it can do so only defeasibly and without certainty.

Relief of facial pain after combined removal of precentral and postcentral cortex

1971 ◽  
Vol 34 (4) ◽  
pp. 537-543 ◽  
Author(s):  
Richard A. Lende ◽  
Wolff M. Kirsch ◽  
Ralph Druckman
Keyword(s):  
Facial Pain ◽  
The Other ◽  
Precentral Gyrus ◽  
Nerve Section ◽  
Content Type ◽  
Burning Pain ◽  
Cortical Localization ◽  
The Brain ◽  
Fine Print ◽  
Frontal Lobotomy

✓ Cortical removals which included precentral and postcentral facial representations resulted in relief of facial pain in two patients. Because of known failures following only postcentral (SmI) ablations, these operations were designed to eliminate also the cutaneous afferent projection to the precentral gyrus (MsI) and the second somatic sensory area (SmII). In one case burning pain developed after a stroke involving the brain stem and was not improved by total fifth nerve section; prompt relief followed corticectomy and lasted until death from heart disease 20 months later. In the other case persistent steady pain that developed after fifth rhizotomy for trigeminal neuralgia proved refractory to frontal lobotomy; relief after corticectomy was immediate and has lasted 14 months. Cortical localization was established by stimulation under local anesthesia. Each removal extended up to the border of the arm representation and down to the upper border of the insula. Such a resection necessarily included SmII, and in one case responses presumably from SmII were obtained before removal. The suggestions of Biemond (1956) and Poggio and Mountcastle (1960) that SmII might be concerned with pain sensibility may be pertinent in these cases.

Detection of Intracranial Signatures of Interictal Epileptiform Discharges from Concurrent Scalp EEG

2016 ◽  
Vol 26 (04) ◽  
pp. 1650016 ◽  
Author(s):  
Loukianos Spyrou ◽  
David Martín-Lopez ◽  
Antonio Valentín ◽  
Gonzalo Alarcón ◽  
Saeid Sanei
Keyword(s):  
Detection Algorithm ◽  
The Other ◽  
Intracranial Eeg ◽  
Scalp Eeg ◽  
Epileptiform Discharges ◽  
Interictal Epileptiform Discharges ◽  
Scalp Electroencephalogram ◽  
Patients With Epilepsy ◽  
Electrical Activities ◽  
The Brain

Interictal epileptiform discharges (IEDs) are transient neural electrical activities that occur in the brain of patients with epilepsy. A problem with the inspection of IEDs from the scalp electroencephalogram (sEEG) is that for a subset of epileptic patients, there are no visually discernible IEDs on the scalp, rendering the above procedures ineffective, both for detection purposes and algorithm evaluation. On the other hand, intracranially placed electrodes yield a much higher incidence of visible IEDs as compared to concurrent scalp electrodes. In this work, we utilize concurrent scalp and intracranial EEG (iEEG) from a group of temporal lobe epilepsy (TLE) patients with low number of scalp-visible IEDs. The aim is to determine whether by considering the timing information of the IEDs from iEEG, the resulting concurrent sEEG contains enough information for the IEDs to be reliably distinguished from non-IED segments. We develop an automatic detection algorithm which is tested in a leave-subject-out fashion, where each test subject’s detection algorithm is based on the other patients’ data. The algorithm obtained a [Formula: see text] accuracy in recognizing scalp IED from non-IED segments with [Formula: see text] accuracy when trained and tested on the same subject. Also, it was able to identify nonscalp-visible IED events for most patients with a low number of false positive detections. Our results represent a proof of concept that IED information for TLE patients is contained in scalp EEG even if they are not visually identifiable and also that between subject differences in the IED topology and shape are small enough such that a generic algorithm can be used.

scholarly journals THE PATHOLOGIC EFFECTS OF STREPTOCOCCI FROM CASES OF POLIOMYELITIS AND OTHER SOURCES

1917 ◽  
Vol 25 (4) ◽  
pp. 557-580 ◽  
Author(s):  
Carroll G. Bull
Keyword(s):  
Spinal Cord ◽  
Guinea Pigs ◽  
The Other ◽  
Laboratory Animals ◽  
Histological Changes ◽  
Other Hand ◽  
Brain And Spinal Cord ◽  
The Brain

Streptococci cultivated from the tonsils of thirty-two cases of poliomyelitis were used to inoculate various laboratory animals. In no case was a condition induced resembling poliomyelitis clinically or pathologically in guinea pigs, dogs, cats, rabbits, or monkeys. On the other hand, a considerable percentage of the rabbits and a smaller percentage of some of the other animals developed lesions due to streptococci. These lesions consisted of meningitis, meningo-encephalitis, abscess of the brain, arthritis, tenosynovitis, myositis, abscess of the kidney, endocarditis, pericarditis, and neuritis. No distinction in the character or frequency of the lesions could be determined between the streptococci derived from poliomyelitic patients and from other sources. Streptococci isolated from the poliomyelitic brain and spinal cord of monkeys which succumbed to inoculation with the filtered virus failed to induce in monkeys any paralysis or the characteristic histological changes of poliomyelitis. These streptococci are regarded as secondary bacterial invaders of the nervous organs. Monkeys which have recovered from infection with streptococci derived from cases of poliomyelitis are not protected from infection with the filtered virus, and their blood does not neutralize the filtered virus in vitro. We have failed to detect any etiologic or pathologic relationship between streptococci and epidemic poliomyelitis in man or true experimental poliomyelitis in the monkey.

Musical training improves memory for instrumental music, but not vocal music or words

2018 ◽  
Vol 48 (1) ◽  
pp. 150-159
Author(s):  
Jonathan M. P. Wilbiks ◽  
Sean Hutchins
Keyword(s):  
Instrumental Music ◽  
Musical Training ◽  
Vocal Music ◽  
Verbal Material ◽  
The Other ◽  
Musical Experience ◽  
Facilitative Effect ◽  
Musical Excerpts ◽  
And Performance ◽  
The Brain

In previous research, there exists some debate about the effects of musical training on memory for verbal material. The current research examines this relationship, while also considering musical training effects on memory for musical excerpts. Twenty individuals with musical training were tested and their results were compared to 20 age-matched individuals with no musical experience. Musically trained individuals demonstrated a higher level of memory for classical musical excerpts, with no significant differences for popular musical excerpts or for words. These findings are in support of previous research showing that while music and words overlap in terms of their processing in the brain, there is not necessarily a facilitative effect between training in one domain and performance in the other.

Beyond the Reward Pathway: Coding Reward Magnitude and Error in the Rat Subthalamic Nucleus

2009 ◽  
Vol 102 (4) ◽  
pp. 2526-2537 ◽  
Author(s):  
Sylvie Lardeux ◽  
Remy Pernaud ◽  
Dany Paleressompoulle ◽  
Christelle Baunez
Keyword(s):  
Subthalamic Nucleus ◽  
Firing Pattern ◽  
Sucrose Solution ◽  
Critical Role ◽  
The Other ◽  
Reward Circuitry ◽  
Reward Delivery ◽  
Reward Pathway ◽  
Subthalamic Neurons ◽  
The Brain

It was recently shown that subthalamic nucleus (STN) lesions affect motivation for food, cocaine, and alcohol, differentially, according to either the nature of the reward or the preference for it. The STN may thus code a reward according to its value. Here, we investigated how the firing of subthalamic neurons is modulated during expectation of a predicted reward between two possibilities (4 or 32% sucrose solution). The firing pattern of neurons responding to predictive cues and to reward delivery indicates that STN neurons can be divided into subpopulations responding specifically to one reward and less or giving no response to the other. In addition, some neurons (“oops” neurons) specifically encode errors as they respond only during error trials. These results reveal that the STN plays a critical role in ascertaining the value of the reward and seems to encode that value differently depending on the magnitude of the reward. These data highlight the importance of the STN in the reward circuitry of the brain.

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