Topic: coordinated movement

topics > science > Group: relationship between brain and behavior

coordinated motor programs
coordinated processes
coordinated robot movement
reflex circle
sensory prediction in coordinated motion


Coordinated movement is one of the mysteries of life. It has a rich structure that defies attempts at formalization. First, there's a regular, rhythmic structure that occurs across wide environmental variations. These structures form simple Fourier series. This indicates that the movement was planned ahead of time as a coordinated motor program.

Coordinated movement involves many degrees of freedom. Although the motor goal may be learned quickly, the coordinated detail can take years to master.

An alternative view of coordinated movement is that it occurs automatically as a result of environmental conditions. (cbb 5/94)

Subtopic: movement studies up

Quote: Fitts studied reciprocal tapping between strips of metal, disc transfers between pins, and pin transfers between strips of holes [»fittPM6_1954]
Quote: the Disney studios pioneered filming actors to study comic action [»thomF_1984]
Quote: use rapid, overlearned, uniform responses to study the capacity of the motor system independently from the sensory system [»fittPM6_1954]

Subtopic: duration vs. extent vs. error up

Quote: duration of independent repetitive motion is essentially independent of its extent; e.g., consistent tapping rate from 1 to 40 mm or handwriting at various sizes [»fittPM6_1954]
Quote: for each amplitude, slightly more errors occurred as tolerances decreased; subjects did not slow down enough [»fittPM6_1954]
Quote: for targeting tasks, the rate of performance increases uniformly as movement amplitude decreases and tolerance increases [»fittPM6_1954]
Quote: the amount of information needed to perform a targeting task is proportional to log(tolerance/amplitude)
Quote: if amplitude and tolerance are fixed, response time is proportional to the information per response
Quote: when measured in information units, the performance capacity of the human motor system is relatively constant over a considerable range of task conditions; 10-12 bits/sec over much of the range from 1 to 10 bits/response
Quote: children made large and fast gestures with curlybot; less accurate reproduction and fell off platform [»freiP4_2000]

Subtopic: coordination vs. command vs. specification up

Quote: neither commands nor rules can determine action; both can be ignored or cause conflict; both must be understood; not basis for coordination [»turvMT_1984]
Quote: specificational information is like a law; determinate, non-negotiable, harmonious, automatic; suitable foundation for coordination [»turvMT_1984]
Quote: is the brain or the muscle the ruling Tzar when you jump, walk, and run? [»bernNA_1947]

Subtopic: gracefulness vs stiffness up

Quote: gracefulness from low internal loading, few internal antagonisms, e.g., UtahHand [»jacoSC4_1986]
Quote: the stiffness of people learning new tasks help overcome the inadequacies of a poor internal model [»hintG_1984]
Quote: the human form in movement displayed far more overall activity than anyone had supposed
Quote: human movement demonstrated the animation techniques of squash and stretch, follow through, overlapping action, timing, and exaggeration
Quote: even though a program may appear graceful, it looks like a Rube Goldberg machine when executed by hand [»dennDC_1978a]
Quote: unlike AI, perhaps nature is graceful all the way down

Subtopic: spatial movement up

Quote: spatial movements (e.g., locomotion) invariably come with flexibility and maneuverability; animals are best [»bernNA_1947]
Quote: movement is a quick and perfect translation from the language of spatial representation to the language of muscle formula [»bernNA_1947]

Subtopic: movement sequence up

Quote: movement sequences (actions) have a chain structure and adaptive variability; allows complex motor tasks with existing motor facilities [»bernNA_1947]
Quote: coordinated, movement sequences (actions) are rare amoung animals; only apes and the highest mammals such as horses, dogs, and elephants [»bernNA_1947]
Quote: movement sequences (actions) typically involve an object; the object ties the movements into meaningful chains; e.g., cooking an egg [»bernNA_1947]
Quote: a movement sequence (action) may contain illogical steps; e.g., tightening a belt in order to loosen it; difficult for animals or small children [»bernNA_1947]
Quote: actions are coordinated sequences of movements that solve a motor problem; e.g., lighting a cigarette; lots of variation [»bernNA_1947]
Quote: speech is a movement sequence (action); linked by a common meaning; with frequent deviations and modifications [»bernNA_1947]
Quote: the grasshopper jumps without seeing where; most jumps are failures [»bernNA_1947]

Subtopic: learning to walk and run up

Quote: precise control of walking and running takes about as long as learning language [»trevC_1984]

Subtopic: two-handed coordination up

Quote: users effortlessly move their hands relative to one another, but they require conscious effort to move relative a fixed 3D space
Quote: with a two-handed interface, users can easily express complex spatial relations; e.g., cut relative to view [»hincK9_1998]
Quote: for distance, bimanual condition twice as accurate as unimanual condition; angle about the same; bimanual, unimanual better than reverse order [»hincK9_1998]
Quote: for precision tasks, the preferred hand acts within the dynamic reference frame formed by the nonpreferred hand; e.g., threading a needle is more difficult if the needle is fixed [»hincK9_1998]
Quote: for human bimanual gestures, the left hand defines the spatial reference, specializes in slow, large-scale movements, and precedes motion of the right hand [»hincK9_1998]
Quote: for difficult, two-handed tasks with tool and target, preferred grip is clearly better than reversed grip; insignificant for easy task [»hincK9_1998]

Subtopic: muscle force up

Quote: muscle force depends on rate of contraction so excess force is converted into acceleration [»hintG_1984]

Subtopic: accurate endpoints up

Quote: in repeated movements, the endpoints are accurate but the path varies widely; e.g., moving a matchbox [»bernNA_1947]
Quote: how can accurate endpoints arise from careless, indifferent paths?
Quote: all possible ways of reaching a point are completely interchangeable

Subtopic: rhythmic structure up

Quote: coordinated movement has a regular, rhythmic structure which interrelates all moving segments [»trevC_1984]
Quote: coordinated movement has homogeneity and an integrated, structural unity [»bernN_1935]
Quote: rhythmical live movements can be determined within a few millimetres by a three or four term Fourier series [»bernN_1935]
Quote: if one cycle of a movement takes 1 sec and can be accurately represented by three sinusoids, then it was organized a second beforehand [»bernN_1935]
Quote: a movement responds as a whole to changes in each small part; response may be spatially and temporally distant from the cause [»bernN_1935]
Quote: voluntary movement is marked by the absence of surprise [»wittL_1958a]

Subtopic: degrees of freedom up

Quote: co-ordination of movement must master redundant degrees of freedom to make it a controllable system [»bernN_1957]
Quote: motor apparatus in man can have hundreds of degrees of freedom in multiple linkages and elasticity of muscles [»bernN_1957]
Quote: difficult to control a weighted stick attached to belt and elastic bands; but like muscles [»bernN_1957]
Quote: co-ordinate movement inhibits the redundant degrees of freedom only at the beginning; it organizes the process as a whole (flexible, expedient) [»bernN_1957]
Quote: two degrees of freedom are much more complicated to automatize than a single degree of freedom [»bernN_1957]

Subtopic: peripheral context up

Quote: conventional flight instruments ignore peripheral vision; requires an instrument scan using focal vision [»stilDL12_2002]
Quote: ambient visual channel optimized for locomotion information; like peripheral vision
Quote: OZ displays a stylized triplane showing power requirements, power available, and the complex interrelationship between power, drag, airspeed, configuration, and performance
Quote: with OZ, pilots can control two planes under turbulence, or simultaneously read one word a second [»stilDL12_2002]

Subtopic: pre-shaping up

Quote: in grasping a ball, fast ballistic movement with pre-shape followed by slow approach with grab [»arbiMA_1987]
Quote: before a hand grabs a ball, it is already preshaped [»arbiMA_1987]
Quote: added touch-sensitive strips for scrolling a graphical interface; easily used; dramatic improvement for experts and novices [»buxtB_1987]
Quote: machines work best if run at the same speed, the same rhythm, with a minimum of moving parts; people excel at coordination and work best if the entire human being is engaged [»drucPF_1974]

Related Topics up

Topic: biology (26 items)
Topic: coordinated motor programs (29 items)
Topic: coordinated processes (8 items)
Topic: coordinated robot movement (10 items)
Topic: reflex circle (20 items)
Topic: sensory prediction in coordinated motion (9 items)
Topic: walking
(20 items)

Updated barberCB 7/05
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