Templates for Neural Dynamics in the Striatum: Striosomes and Matrisomes

Handbook of Brain Microcircuits ◽

10.1093/med/9780190636111.003.0012 ◽

2017 ◽

pp. 133-142

Author(s):

Ann M. Graybiel

Keyword(s):

Neural Dynamics ◽

Major Influence ◽

Human Language ◽

Motor Functions ◽

Subcortical Region ◽

System P ◽

Human Disorders ◽

Lower Structure ◽

Horizontal Layers

The striatum appears to be a relatively simple forebrain region compared to the overlying neocortex, with its horizontal layers and vertical columns. In fact, the striatum in mammals has a sophisticated architecture of its own. This large subcortical region is now suspected of having a major influence on how the neocortex carries out its own functions—even functions related to human language. Furthermore, abnormalities in the striatum are increasingly being discovered in human disorders affecting both cognitive and motor functions. It is, as a consequence, increasingly difficult to see the neocortex as a higher structure and the striatum as a lower structure in terms of their influence on behavior. The chapter is not a full review of this topic, but it points out some findings from the author’s laboratory that hint at such functions for the striosomal system.

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In and Out of the Central Nervous System

10.1093/med/9780190614966.003.0007 ◽

2016 ◽

Author(s):

Michael J. Aminoff

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Experimental Approach ◽

Cranial Nerves ◽

Motor Functions ◽

System P ◽

The Central Nervous System ◽

Experimental Findings ◽

The Brain

In 1811, Bell had printed privately a monograph titled Idea of a New Anatomy of the Brain. In it, Bell correctly showed that the anterior but not the posterior roots had motor functions. François Magendie subsequently showed that the anterior roots were motor, and the posterior roots were sensory. This led to a dispute about priority during which Bell republished some of his early work with textual alterations to support his claims. Bell was involved in a similar dispute with Herbert Mayo concerning the separate functions of the fifth (sensory) and seventh (motor) cranial nerves, and Mayo today is a forgotten man. In both instances, Bell deserves credit for the concepts and initial experimental approach, and Magendie and Mayo deserve credit for obtaining and correctly interpreting the definitive experimental findings.

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The neural correlates of consciousness under the free energy principle: From computational correlates to computational explanation

10.31234/osf.io/7gefk ◽

2020 ◽

Author(s):

Wanja Wiese ◽

Karl Friston

Keyword(s):

Free Energy ◽

Sensory Stimulation ◽

Neural Correlates ◽

Neural Dynamics ◽

Energy Principle ◽

Free Energy Principle ◽

Neural Correlates Of Consciousness ◽

System P ◽

Computational Explanation ◽

Computational Systems

How can the free energy principle contribute to research on neural correlates of consciousness, and to the scientific study of consciousness more generally? Under the free energy principle, neural correlates should be defined in terms of neural *dynamics*, not neural states, and should be complemented by the research on *computational* correlates of consciousness -- defined in terms of probabilities encoded by neural states.We argue that these restrictions brighten the prospects of a computational explanation of consciousness, by addressing two central problems. The first is to account for consciousness in the absence of sensory stimulation and behaviour. The second is to allow for the possibility of systems that implement computations associated with consciousness, without being conscious, which requires differentiating between computational systems that merely simulate conscious beings and computational systems that are conscious in and of themselves.Given the notion of computation entailed by the free energy principle, we will derive constraints on the ascription of consciousness in controversial cases (e.g., in the absence of sensory stimulation and behaviour). We show that this also has implications for what it means to *be*, as opposed to merely *simulate* a conscious system.

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Language Design and Communicative Competence: The Minimalist Perspective

10.31234/osf.io/85xes ◽

2019 ◽

Author(s):

Elliot Murphy

Keyword(s):

Natural Selection ◽

Crucial Role ◽

Communicative Competence ◽

Language Evolution ◽

Minimalist Program ◽

Language Design ◽

Human Language ◽

Computational System ◽

Linguistic Communication ◽

System P

In the Minimalist Program, the place of linguistic communication in language evolution and design is clear: It is assumed to be secondary to internalisation. I will defend this position against its critics, and maintain that natural selection played a more crucial role in selecting features of externalization and communication than in developing the computational system of language, following some core insights of minimalism. Alongside this computational system, human language exhibits ostensive-inferential communication via open-ended combinatorial productivity, and I will explore how this system is compatible with – and does not preclude – a minimalist model of the language system.

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Comparison of TEM and STM observations of small silver clusters on different carbon supports

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017445x ◽

1990 ◽

Vol 48 (4) ◽

pp. 264-265

Author(s):

Bernd Tesche ◽

Tobias Schilling

Keyword(s):

Vibration Isolation ◽

Pyrolytic Graphite ◽

Carbon Film ◽

Silver Clusters ◽

Carbon Supports ◽

Stacking Order ◽

System P ◽

High Resolution Tem ◽

High Degree ◽

Degree Of Order

The objective of our work is to determine:a) whether both of the imaging methods (TEM, STM) yield comparable data andb) which method is better suited for a reliable structure analysis of microclusters smaller than 1.5 nm, where a deviation of the bulk structure is expected.The silver was evaporated in a bell-jar system (p 10−5 pa) and deposited onto a 6 nm thick amorphous carbon film and a freshly cleaved highly oriented pyrolytic graphite (HOPG).The average deposited Ag thickness is 0.1 nm, controlled by a quartz crystal microbalance at a deposition rate of 0.02 nm/sec. The high resolution TEM investigations (100 kV) were executed by a hollow-cone illumination (HCI). For the STM investigations a commercial STM was used. With special vibration isolation we achieved a resolution of 0.06 nm (inserted diffraction image in Fig. 1c). The carbon film shows the remarkable reduction in noise by using HCI (Fig. 1a). The HOPG substrate (Fig. 1b), cleaved in sheets thinner than 30 nm for the TEM investigations, shows the typical arrangement of a nearly perfect stacking order and varying degrees of rotational disorder (i.e. artificial single crystals). The STM image (Fig. 1c) demonstrates the high degree of order in HOPG with atomic resolution.

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