Scientific Understanding of Consciousness |
Fixed Action Patterns (FAPs)Rudolfo Llinás adopted the Fixed Action Pattern (FAP) concept from ethology. (Llinás; I of the Vortex, 133) Historical note: Von Frisch/Lorenz/Tinbergen/ - Nobel Prize in Physiology or Medicine in 1973. Lorenz - founder and namer of ethology, famous for his work on imprinting in geese, discovered and developed, along with Tinbergen, classic concepts of ethology. Fixed Action Pattern (FAP): Behavior that once initiated, goes to completion. Central Pattern Generators (CPGs) generate neuronal patterns of activity that drive FAPs such as the walking FAP. (Llinás; I of the Vortex, 134) Simple motor responses can be assembled into more complex behaviors under voluntary control by the forebrain. The precise patterns of motor response are organized locally in the brain stem reticular formation. (Kandel; Principles of Neural Science, 887) Motor cortex, supplementary motor cortex, and neostriatum and may be the structures that store the skill-based information and long-term memory that allow the smooth execution of skill movements. (Squire & Kandel; Memory, 178) A structure of action is a temporal gestalt, like a melody. (Fuster; Prefrontal Cortex, 345) FAPS are subject to modification; they can be learned, remembered, and perfected. (Llinás; I of the Vortex, 153)
Research Study — Motor Cortex Neurons Directly Influence Motor Output Research Study — Motor Learning Spatiotemporal Neural Activity Patterns Research Study — Locomotor Control by Networks of Spinal Neurons Research Study — Gestures in Bird Song
Language is a FAPLanguage itself is a FAP. Broca's area is responsible for the generation of motor aspects of language. (Llinás; I of the Vortex, 151) The motor command sequences that underlie the production of human speech are arguably the most complex that ordinary people attain. (Philip Lieberman; Human Language, 44) With respect to motor action, we should not fail to heed that the utterances of language, which are directed by purely representational processes and not by external stimuli, are guided by an on-line processor in one or more areas of the prefrontal cortex. (Goldman-Rakic; Circuit Model of Working Memory, 132)
Research Study — Speech Organization in Cortex — Production of fluent speech requires the precise, coordinated movement of multiple articulators (for example, the lips, jaw, tongue and larynx) over rapid time scales. We found speech-articulator representations that are arranged somatotopically on ventral pre- and post-central gyri, which were coordinated temporally as sequences during syllable production.
Every Motor and Cognitive Act Is a Synthesis of Self-Generated Circuit ActivityCortical activity is in perpetual motion, and every motor and cognitive act is a synthesis of self-generated, circuit maintained activity and environmental perturbation. (Buzsáki; Rhythms of the Brain, 335) Movement is facilitated by multitudes of fixed action patterns (FAPs) that respond to relatively high-level signals in the brain. FAPs generally operate at a subconscious level but nonetheless result in visual and other sensory signals that can rise to the level of Consciousness. Humans, as well as all animals, have innate FAPs as well as learned FAPs. Learned FAPs include those to produce leg motions for walking and for riding a bicycle and finger motions for playing a violin. Innate FAPs include those of a newborn infant for the motions such as sucking, crying and yawning. Anyone who skis mountain trails, plays a piano, or drives an automobile home on 'automatic pilot,' knows that stereotyped sensory-motor skills -- dubbed zombie behaviors -- require rapid and sophisticated sensory processing. (Tsuchiya & Koch; Consciousness and Attention, 74) Reactions that constitute crying and sobbing are ready and active at birth. These reactions are automatic and largely stereotyped. (Damasio; Looking for Spinoza, 35) Learning can modulate the execution of a stereotyped pattern. Our laughter or crying plays differently in different circumstances, just as the musical notes that constitute a movement of a sonata can be played in very different ways. (Damasio; Looking for Spinoza, 35) All of the automatic and stereotyped reactions are aimed at regulating the life process and promoting survival. (Damasio; Looking for Spinoza, 35) Basic reflexes include the startle reflex, which organisms deploy in reaction to a noise or touch, or as the tropisms that guide organisms from extreme heat or extreme cold, or the way from dark into light. (Damasio; Looking for Spinoza, 31) Primary acoustic startle reflex is controlled by brainstem nuclei. (Robbins; Pharmacology, Arousal, Attention, 208) Bulk of all voluntary and deliberate behavior consists of simple and automatic acts, old habits, and familiar percepts, most of it integrated at hierarchically lower cortices and basal ganglia. (Fuster; Prefrontal Cortex, 346) It is not known where the memory trace of a motor skill is ultimately stored. (Squire & Kandel; Memory, 178) Organization of interneurons in the spinal cord for vertebrates is quite complex. (Kandel; Principles of Neural Science, 1248) Planning motor actions can be implemented in terms of a sequence of movement trajectories based on a stored repertoire of elementary movements. [FAPs] These basic movements can then be transformed and concatenated together to generate more complex movements. [Stereotyped motor programs] [FAPs] (Ullman; Sequence Seeking Counterstreams, 264) The well-connected motor cortex guides complex actions that require the coordination of several muscles. (Ratey; User's Guide to Brain, 164) Motor system is capable of selecting among a large repertoire of stereotyped motor routines. [Stereotyped motor programs] [FAPs] (Van Essen; Dynamic Routing Strategies, 274) Specific Motor Action Organized by Inferior Parietal LobulesThe parietal lobe of primates consists of three main sectors: the postcentral gyrus, the superior parietal lobules, and the inferior parietal lobules (IPL). (Rizzolatti; Grasping Movements, 438) The IPL can be conceived as a set of largely independent modules, each of which is responsible for the organization of a specific motor action. (Rizzolatti; Grasping Movements, 438) Motor information, as well as visual information for action, is centrally coded in abstract terms. (Rizzolatti; Grasping Movements, 440) Information for complex acts is compressed in populations of specific units. (Rizzolatti; Grasping Movements, 440)
Researchers use various terms for the concept of FAPsCentral Pattern Generating networks (CPGs). -- (diagram) (Squire; Fundamental Neuroscience, 757) Dispositions produce a variety of results. They can generate actions of many kinds in many levels of complexity -- the release of hormones into the bloodstream; the contraction of muscles in the viscera or of muscles in a limb or in the vocal apparatus. (Damasio; Self Comes to Mind, 143) Instincts, automatically programmed behaviors, "fixed acts", (Hobson; Dreaming as Delirium, 143) The resulting outcomes of our choices can depend on entirely automatic behavior. (Hobson; Consciousness, 82) Stereotypical patterns of movement. (Purves, Neuroscience, 399) Expressions of emotion such as crying and laughing are controlled by the amygdala and brainstem. (Ratey; User's Guide to Brain, 174) Many, if not most, motor actions in response to external events are rapid transient, stereotyped, and nonconscious. (Koch; Quest for Consciousness, 305) Commands from prefrontal cortex, motor cortex, basal ganglia, cerebellum, spinal cord. FAPs can come from any of these areas. Many human behaviors are reflexes programmed into our brains when we are rewarded or punished for taking a particular action. (Frank; Learning and the Basal Ganglia, 151) Basal ganglia are important in learning from feedback in the formation of good and bad habits. (Frank; Learning and the Basal Ganglia, 151) Set is the Preparation of Neural ResourcesSet is the preparation of neural resources for expected sensory input or motor response in the course of executive performance. (Fuster; Prefrontal Cortex, 180) Actions may involve the executive representation (cognits) of high order, in the form of schemas, temporal gestalts, scripts, or rules of action. (Fuster; Prefrontal Cortex, 347) In the organization of complex, goal directed behavior, a cascade of activation from higher frontal networks to lower ones, with monitoring and correction action at every step. (Fuster; Prefrontal Cortex, 348) Set begins at high, prefrontal, levels of the hierarchy that encode rules, plans, and long-term goals. (Fuster; Prefrontal Cortex, 348) To understand the structure and synthetic functions of the frontal cortex in behavior, and its role in the perception-action cycle, it is helpful to conceptualize all behavior as a hierarchical order of structured units of sensation and action. (Fuster; Prefrontal Cortex, 360)
Stereotyped Movements involve Basal Ganglia and CerebellumImplicit memory provides stereotyped but extremely reliable movements, and involves the basal ganglia and cerebellum. (Ratey; User's Guide to Brain, 200) Basal ganglia are responsible for the automatic execution of a learned motor plan. (Afifi; Functional Neuroanatomy, 290) As a motor skill is learned, the basal ganglia take over the role of automatically executing the learned strategy. (Afifi; Functional Neuroanatomy, 290) In the basal ganglia and the cerebellum, we have representations of learned and automatic actions, which at one time may have depended on the cerebral cortex, but are now relegated to lower levels of sensory-motor integration. (Fuster; Prefrontal Cortex, 361) Stroke victims with cerebellar damage struggle for the rest of their lives with simple physical maneuvers like walking up and down stairs. Instead of being able automatically to put their feet down in the right place on a stairstep, stroke victims with cerebellar damage have to consciously think about where to put their feet. (Ratey; User's Guide to Brain, 305) At the level of the cerebral cortex, the representations of sensation (now perception) and of action associated with it become more complex and more dependent on new plans or recent experience. (Fuster; Prefrontal Cortex, 361) The basal ganglia receive inputs from all parts of the cerebral cortex, including the motor cortex, and have outputs directed strongly toward the premotor and prefrontal cortex by which they could influence movement initiation. (Rolls & Treves; Neural Networks, 206)
Research study — central pattern generators (CPGs) in zebrafish Research Study — Basal Ganglia and Corticostriatal Pasticity in Learning
Cerebellum heavily involved with FAPsCerebellum is believed to directly contribute to the execution of movement details, and to the acquisition of conditioned reflexes and body adjustments to changing environmental inputs. (Eichenbaum; Neuroscience of Memory, 240) Attention is Coordinated by CerebellumAutistic patients and cerebellum stroke victims find it harder to shift their attention quickly from one thing to another. People with autism and those with cerebellum damage are slower to pick up on and react to new stimuli in the environment, making it harder for them to manage social interactions, which are characterized by constantly changing stimuli. Like putting our feet where we want them without having to think about it, our ability to put our attention where we want it without having to think about it is coordinated by the cerebellum. (Ratey; User's Guide to Brain, 305ff) Complex Pattern Generator (CPG) networksLocation of different complex pattern generator (CPG) networks that coordinate different motor patterns in vertebrates. -- (diagram) Spinal cord contains CPGs for locomotion and protective reflexes. Brain stem contains CPG for breathing, chewing, swallowing, and saccadic eye movements. Hypothalamus in the forebrain contains centers that regulate eating and drinking. Cerebral cortex is important, particularly for fine motor coordination involving hands and fingers and for speech. (Squire; Fundamental Neuroscience, 759) Cerebellum, basal ganglia, and hippocampus create a system of interconnections for whole categories of information, as well as patterns of motor activity. (Ratey; User's Guide to Brain, 143) Writing Your Signature -- A Recursive Flow of FAPsWriting your signature activates a recursive flow of FAPs to produce the muscular movements. These FAPs involve the premotor cortex, motor cortex, basal ganglia, cerebellum, brainstem reticular formation, and stereotyped motor responses in the spinal cord. The recursive flow of FAPs is initiated by decision circuitry of working memory in the frontal cortex along with association circuitry in the parietal cortex. FAPs are mediated by procedural memory circuits that function unconsciously. The recursive flow of FAPs in neural circuitry proceeds along a timeline of tens of milliseconds in neural circuitry along local pathways. Each recursion of positive feedback along the stream of synaptic connections triggers the activation of closely adjacent synapses to produce the hierarchy of FAPs for the following segment of the signature. The hierarchy of FAPs and the timeline of generating a recursive sequence of associated FAPs has been produced as procedural memory during a person's lifetime experience of learning to write. In this way the recursive flow of closely adjacent hierarchies of procedural-memory synaptic connections forming the FAPs produces the unique muscular movements that characterize a persons written signature. Nested Subroutines MetaphorFAPs, invoking lower-level FAPs, invoking even lower-level FAPs, and so on, in a nested hierarchy harkens to an analogous situation of nested computer subroutines. FAPs involve the brainCompare FAPs, which include the brain, with spinal reflexes in which the brain is not involved. FAPS group simple reflexes and lower FAPs into functional modules capable of more complex goal-oriented behavior. FAPs are thought to originate in the basal ganglia, while Central Pattern Generators (CPGs) generate neuronal patterns of activity that drive FAPs such as the walking FAP. Identify the brain systems supporting a task when it is novel and effortful compared with systems engaged when the task is routine and reflexive. (Raichle; NCC Cognitive Skill Learning, 655) The supervisory attention system provides a mechanism whereby elements or schemas within the lower-level contention-scheduling system for routine, reflexive behaviors and thoughts can be temporarily modified by activating or inhibiting particular elements within it. (Raichle; NCC Cognitive Skill Learning, 664)
FAPs (fixed action patterns) are sets of ready-made motor patterns which produce well-defined and coordinated movements, e.g. walking, swallowing, speaking; some can be learned (e.g. playing guitar), most can be modified by experience. They are not reflexes, although some are highly automatized, others are activated by volition. FAPs reduce the immense degrees of freedom of the motor system in movements. They are based on the basal ganglia, which are connected extensively to the thalamus and the cortex. FAPs liberate the self to spend time and attention on other things. Llinás interprets emotions as another kind of FAPs with premotor (not motor) actions, providing the trigger and internal context for action, then to be shown via other FAPs, e.g. as facial expressions. Llinás also interprets language as a premotor FAP. Basal forebrain and hypothalamic nuclei, some nuclei in the brainstem tegmentum, and brainstem nuclei that control the movement of the face, tongue, pharynx, and larynx are the ultimate executors of many behaviors that define the emotions, from courting or fleeing to laughing and crying. (Damasio; Looking for Spinoza, 63) Reticular formation neurons organize mastication, facial expressions, reflexive orofacial behaviors such as sneezing, hiccuping, yawning, swallowing. (Purves; Neuroscience, 398) Facial expressions, vocalizations, body postures, and specific patterns of behavior are enacted via emotion. (Damasio; Looking for Spinoza, 63) The dorsal visual system helps with executing actions, for example in shaping the hand appropriately to pick up a selected object. Often the sensori-motor operation is performed implicitly, i.e. without conscious awareness. (Rolls; Emotion Explained, 427)
Embryos generate continuous bouts of muscle tremor, not unlike small epileptic fits. Epileptic activity may be among the most primitive of all functional states -- a bit like sneezing. (Llinás; I of the Vortex, 63) Llinás mentions the strange case of a patient who has been in coma for the last twenty years as a result of a stroke, which destroyed most of the cortex, leaving part of Broca’s area, the thalamus and the basal ganglia intact. Now, the patient in a vegetative state, occasionally still utters words. (Llinás; I of the Vortex, 151) Laughing and CryingStimulation of a small region of the supplementary motor area (SMA) in the left frontal lobe can consistently and exclusively evoke laughter. The laughter-producing brain patch is small, measuring about 2 cm x 2 cm. (Damasio; Looking for Spinoza, 75) There may be nuclei in the brainstem capable of producing the motor patterns of laughter. (Damasio; Looking for Spinoza, 76) In the case of laughter, it appears that the initial triggering sites are in the medial and dorsal prefrontal region in regions such as the supplementary motor area (SMA) and the anterior cingulate cortex. (Damasio; Looking for Spinoza, 76) In the case of crying, the critical triggering sites are likely to be in the medial and ventral prefrontal region. (Damasio; Looking for Spinoza, 76)
FAPs and SchemataWhen we face a problem, we draw upon mental schemata, organized bundles of stored knowledge. (LeDoux; Synaptic Self, 177)
FAPs are implemented at the level of the basal gangliaFAPs are most probably implemented at the level of the basal ganglia and put into context by the reentry of the basal ganglia output into the ever-cycling thalamocortical system. (Llinás; I of the Vortex, 144) Striatum is a key element in the pathway for sequence learning and other aspects of habit learning involving the acquisition of stereotyped and unconscious behavioral repertoires. (Eichenbaum; Neuroscience of Memory, 250) Cognition and consciousness probably evolved from the emotional states that trigger FAPs. (Llinás; I of the Vortex, 168) The brain uses many fixed action patterns, which are not normally within the realm of consciousness. Fixed Action Patterns are automatic brain modules that make complex movements; well defined motor patterns, (walking, swallowing). Nervous systems are an exclusive property of actively moving creatures. (Llinás; I of the Vortex, 17) Overall organization of neural structures in the control of movement - (diagram) (Purves, Neuroscience, 372) Compare signals from external world with internal signals and memory of prior episodes to produce control signals for movement and behavior. Edelman gestures, -- synergy – a class of related gestures (Edelman, Remembered Present, 121) The spinal cord is capable of sustaining a rhythmic movement -- like a decapitated chicken -- but it cannot organize and generate a directed movement. (Llinás; I of the Vortex, 44) Movement control example – ConversationConsider the brain activity during a conversation between friends. Both cognition and emotion are active, driving motivation for speech activation. Speech control in Broca’s area causes speech FAPs to be released from the basal ganglia, which in turn causes the speech musculature to be activated. Now consider what happens when a sudden loud noise occurs. The body responds with a startle. The loud sound has entered the ears, cervical nerve VIII, reticular formation, filtered and assessed, signal transmitted to the amygdala, startle response of the body, perhaps with a explicative vocalization, “What was that?!!” The startle response and explicative vocalization were processed outside of consciousness. These startle responses are FAPs.
Research Study — Automatic Processes in Behavior — Much human behavior is not driven by deliberation upon the consequences of actions, but is automatic, cued by stimuli in the environment, resulting in actions unaccompanied by conscious reflection.
Excerpts from science experts
Stereotyped motor behavior bypasses Consciousness. (Koch, Quest for Consciousness, 235) Walking Sneeze Play Violin All modalities (Koch, Quest for Consciousness, 214) Some researchers refer to these fixed action patterns by the philosopher’s term “Zombie agents.” (Koch, Quest for Consciousness, 205, 226) A zombie is a non-thinking automaton. Note about Christof Koch’s Use of the term ‘Zombie Agents’Koch uses the philosopher’s term ‘Zombie Agent’. I don’t like the term. It suggests a mystical, unscientific connotation, whereas there is nothing mystical or unscientific about the phenomenon Koch calls Zombie Agents. I much prefer the term “Fixed Action Pattern” (FAP), which is derived from ethology, the study of animal behavior. This term is more descriptive and carries no mystical connotations. Rodolfo Llinás uses the term FAP to apply to a host of complex human unconscious movements such as riding a bicycle or playing a violin. Although the acquisition and training of zombie behavior (FAPs) requires Consciousness, the brain can eventually take over and command the unconscious FAPs that formerly required Consciousness. (Koch, Quest for Consciousness, 235, 247) Hybrid zombie agent plus flexible Consciousness module (Koch, Quest for Consciousness, 237) Emotional FAPsFacial expressions generated by emotional states are produced by unconscious FAPs for a smile, a grimace, surprise, intense pain, etc. (Llinás; I of the Vortex, 157) Musicians play instruments using FAPs developed through practiceA pianist playing a concerto may execute passages without conscious attention, note by note, but simultaneously may plan consciously or think ahead about an upcoming musical phrase or tempo. (Edelman; Wider than the Sky, 94) Practicing musical passages will eventually result in the ability to "rattle them off" without detailed attention. (Edelman; Wider than the Sky, 93) Finger movements of a violin or piano soloist that have been learned during years of practice are released without thought during a performance. The soloist’s thoughts are at a higher level of creating a sound that expresses the desired emotional state. When a soloist plays a concerto with a symphony orchestra, the concerto is played purely from memory. This highly specific motor pattern FAP is stored somewhere in the brain during practice sessions and is released during the performance. (Llinás; I of the Vortex, 169) In commanding the FAPs, certain portions of the cortex may be engaged in interactions with the basal ganglia without being directly involved in the operation of the dynamic core. (Edelman; Wider than the Sky, 94) When you sing a tune, either aloud or silently within your head, the FAP for the tune probably resides and arises in the basal ganglia and its connections with the thalamocortical system. Comment about learned FAPsI want to comment about the FAPs used to drive a car. All of the FAPs learned for driving on the right-hand-side of the road in the USA could lead to disastrous results when driving on the left-hand-side in England. I can envision myself making disastrous impulsive movements in quick-response situations. All the learned FAPs for USA driving could be disastrous when impulsively applied in England.
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