7 principles for command and the neural causation behavior.pptx

Presentación sobre los fundamentos de causalidad en la investigación empírica sobre modelos animales y sus implicaciones para el desarrollo de modelos en humanos.

1. 7 principles for command and the neural causation behavior Marc Grifell Guardia

2. Abstract The concept of command is central to motor control theories The used concept refers to the process of triggering behavioral acts by individual command neurons This concept is inadequate and useless. A new concept based on 7 principles is proposed in this article.

3. Introduction Appeals to the intuitive idea that there are higher-order interneurons with the specialized responsibility for initiating behavior patterns.

4. Introduction The best attempt to formulate command has been through the command neuron experiment (CNE) Kupfermann and Weiss, 1978 CNE proposed three tests to demonstrate and define command neurons: (esquema de neurofisio, lesio i estimulacio) Correlation test Necessity test Sufficiency test If failing either 2 or 3, the neuron would be considered a command element but would no be attributed functional responsability

5. Introduction No one has achieved to demonstrate a command system Check the book Decoding Neural Circuit Structure and Function, chapter 11 Thus, we have the situation in which command is widely used but its only explicit conceptualization has been refuted.

6. Principles of command Defined independently of any single causal paradigm Defined independently of any single methodology and enriched by many Defined in functional rather than structural terms Related to observable and quantifiable behavior Understanding behavior in the context of its adaptative and evolutive significance Command can be localized only in a metaphorical sense: this is because comand is a function.

7. 1.- Causal basis of command Rigor of proof of causation is at best a matter of degree and usually comes in stages. Necessity and sufficiency causation is entrenched and unchallanged in neuroscience. N&S are thought to be N&S for neurobiological explanations N&S is not sufficient, as they are only explanations/interpretations, not facts N&S may not necessary, as failed to be applicable in complex systems and we shall still be open to the discovery of new causal theories

8. 1.- Causal basis of command Table 1: Facts versus explanation of facts

9. 2.- Methodological basis of command Demonstrations cannot be restricted to any particular experimental approach Lesions and stimulation techniques are not obsolete as long as we do not try to equate them to necessity and sufficiency

10. 3.- Functional basis of command Many have assumed that command is a function confined to specific structures BUT Function is suggested by structure but not defined by it Similar structures can have very different roles. Liberation of command from anatomical specification (interneurons) Command is best thought as a function, resulting in a behavioral act. It describes what a network does and is not limited or localized to any particular part of the CNS

11. 4&5.- Neuroethological basis of command Command cannot be defined only in neurophysiological terms Defining in functional and quantifiable behaviors resolves previous experimental contradictions The concept of command is the link between the neurophysiological language and the behavioral. Cannot be developed without the behavioral analysis.

12. 4&5.- Neuroethological basis of command The concept of command (Neurobehavioral) must be structured by the behavioral definition, and this definition cannot be arbitrary. The definition of behavior excludes neural structures and its relationships and refers to motor behavior. Behavior: a motor expression that leads to an identifiable activity for which the animal has evolved a response (5th principle: neuroethology). Behavior is delineated by the inputs, the outputs and the conditions in which they occur. There are contradictions between neurophysiological and neurobehavioral experiments.

13. 4&5.- Neuroethological basis of command Before one can arrive at satisfactory interpretations of behavior, neurophysiological mechanisms must be studien under Enviromentally relevant conditions

14. 6.- Command as a dynamic property Command is a dynamic function of the neural tissue A command system is a set of neural elements that are involved in the behavioral action. Relates two exclusive domains. The system changes depending on the environment, the behaviors displayed...

15. 6.- Command as a dynamic property The output of the comand system is a function of its inputs and conditions A function of the system is a representation of the operation of the system. In the same way, command function in only an abstract concept This is different from the idea that command is only what turns the pattern generation on, the command system is also the pattern generator. The command system changes in time as in recruits its appropriate subsystems and then abandons them when a new behavior pattern is executed

16. 7.- Metaphorical localization of command We can localize command in the same way that learning is a behavioral concept (learning is not done by learning cells) Neurons don’t learn, animals do. In the same way, command is a larger scale concept than the neurophysiological events that lead to its expression, it doesn’t exist in space, its location is a menaingless concept. Funcions are not locable, elements are

17. Principles of command Defined independently of any single causal paradigm Defined independently of any single methodology and enriched by many Defined in functional rather than structural terms Related to observable and quantifiable behavior Understanding behavior in the context of its adaptative and evolutive significance Command can be localized only in a metaphorical sense: this is because comand is a function.

18. Conclusions Command neuron experiment is defined as a reactive system in which information is linear. The command concept was structured to avoid the limitations which prevent us from knowing the existence of the neural mechanisms we are trying to discover Replace old images of circuits with new ways of displaying information

19. Conclusions The new concept do not eliminate the search of specific functional roles but realizes that the command neurons may interact in different manners