C18- Postural Control
43 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Maintaining posture during periods of inactivity, such as sleep, requires the same level of muscle activation as during active tasks.

False (B)

The primary function of postural control is to facilitate rapid, uncoordinated movement.

False (B)

Postural control solely depends on visual input; proprioception and vestibular signals have minimal effect.

False (B)

The evolution to bipedalism has decreased dependence on muscle activation for maintaining posture.

<p>False (B)</p> Signup and view all the answers

Posture can be simply defined as a static state that involves no muscular activity.

<p>False (B)</p> Signup and view all the answers

Exocentric coordinates for postural control relate to the individual's body parts relative to each other.

<p>False (B)</p> Signup and view all the answers

The number of degrees of freedom that postural control manages is relatively limited for efficient movement.

<p>False (B)</p> Signup and view all the answers

Postural control's function primarily involves maintaining a diverse range of positions and not a fixed, singular stance.

<p>True (A)</p> Signup and view all the answers

The biceps muscle typically activates before the gastrocnemius muscle when a person is pulling a handle, as the primary mover.

<p>False (B)</p> Signup and view all the answers

Feedforward control relies on information processed by the vestibular, visual, and somatosensory systems.

<p>False (B)</p> Signup and view all the answers

With repeated trials of pulling a handle, the gastrocnemius muscle's rapid postural response will occur progressively later.

<p>False (B)</p> Signup and view all the answers

The somatosensory system provides information regarding geocentric coordinates and linear acceleration.

<p>False (B)</p> Signup and view all the answers

The vestibular system adapts to rapidly changing conditions and stable surroundings with equal ease.

<p>False (B)</p> Signup and view all the answers

Postural actions are employed to maintain posture, not to recover from its loss.

<p>False (B)</p> Signup and view all the answers

One of the functions of postural control is to provide a reference frame and stability for eye, head, and limb movements.

<p>True (A)</p> Signup and view all the answers

The ability to perform dual tasks improves with age due to increased attentional capacity.

<p>False (B)</p> Signup and view all the answers

Stability limits are static and do not change based on the individual, task or environment.

<p>False (B)</p> Signup and view all the answers

If the body's center of mass (COM) moves beyond the stability limits, the body still maintains stability.

<p>False (B)</p> Signup and view all the answers

Motor skills that emerge from the interaction between the individual, the environment, and the task are known as 'postural controls'.

<p>False (B)</p> Signup and view all the answers

In a quadrupedal stance, the center of mass is located directly at one of the four corners defining the stability area.

<p>False (B)</p> Signup and view all the answers

The bipedal posture has broader stability limits than the quadrupedal posture because of the wider stance.

<p>False (B)</p> Signup and view all the answers

The skeletal structure is fully sufficient to maintain an upright position without any muscular action to counter-balance gravity.

<p>False (B)</p> Signup and view all the answers

Postural stability in the frontal and sagittal planes is maintained by one integrated system.

<p>False (B)</p> Signup and view all the answers

The vestibular system directly connects to the spinal cord for postural control.

<p>False (B)</p> Signup and view all the answers

Cutaneous afferents always function strictly as touch receptors.

<p>False (B)</p> Signup and view all the answers

The primary proprioceptive information for postural control comes from the pressure receptors on the top surface of the foot.

<p>False (B)</p> Signup and view all the answers

Straightening reactions are independent of the motor programs related to an ongoing movement.

<p>False (B)</p> Signup and view all the answers

The spinal component of postural control is primarily influenced by the visual system.

<p>False (B)</p> Signup and view all the answers

Meissner corpuscles and Merkel disks are examples of proprioceptors in the skin.

<p>False (B)</p> Signup and view all the answers

The Golgi tendon organ is a form of muscle spindle receptor that reports muscle contraction.

<p>False (B)</p> Signup and view all the answers

The visual system directly influences the spinal cord's role in controlling posture.

<p>False (B)</p> Signup and view all the answers

Anticipatory postural adjustments occur completely independent of cortical influence.

<p>False (B)</p> Signup and view all the answers

Ruffini and Pacini receptors are responsible for providing egocentric information to the spinal component of the nervous system.

<p>True (A)</p> Signup and view all the answers

Somatic stimuli, including proprioception, do not contribute to the spinal component of posture control.

<p>False (B)</p> Signup and view all the answers

Maculae are activated by constant velocity, not perturbations.

<p>False (B)</p> Signup and view all the answers

Force acting on the same direction as gravity increases the action of macular receptors, causing a homogenous distribution of muscular tone on antigravity muscles.

<p>True (A)</p> Signup and view all the answers

Semicircular canals primarily help with organization of posture control.

<p>False (B)</p> Signup and view all the answers

Vestibular reflexes cause a flexion of the limb in the direction of head rotation, plus an extension of the other limb.

<p>True (A)</p> Signup and view all the answers

To isolate the effects of the maculae, it is necessary to activate the proprioceptors of the neck.

<p>False (B)</p> Signup and view all the answers

Rotating the head clockwise (blocking the neck) induces a vestibular reflex resulting in the extension of the right limb and flexion of the left limb.

<p>False (B)</p> Signup and view all the answers

The vestibule is more sensitive to constant stimuli rather than to changes.

<p>False (B)</p> Signup and view all the answers

Rotating the neck clockwise (blocking the head) induces a neck proprioceptive reflex resulting in the flexion of the right limb and the extension of the left one.

<p>False (B)</p> Signup and view all the answers

Forces acting in different directions relative to the force of gravity modulate macular discharges resulting in an action on muscle tone that helps counteract the perturbation force.

<p>True (A)</p> Signup and view all the answers

Flashcards

Posture

An actively stabilized orientation of the body maintained over time.

Postural Control

The ability to maintain proper body alignment and orientation.

Egocentric Coordinates

Positioning of body parts relative to one another.

Exocentric Coordinates

Positioning of body parts in relation to the environment.

Signup and view all the flashcards

Geocentric Coordinates

Positioning of body parts in relation to gravity.

Signup and view all the flashcards

Muscle Synergy

Coordinated muscle activities that maintain stable posture.

Signup and view all the flashcards

Postural Functions

Services by postural control for maintaining body positions.

Signup and view all the flashcards

Evolution of Posture

The transition from quadrupedal to bipedal locomotion.

Signup and view all the flashcards

Spinal component of posture control

Part of posture control influenced by somatic stimuli (proprioception and cutaneous reception).

Signup and view all the flashcards

Somatic stimuli

Sensory inputs from the body, primarily proprioceptive and cutaneous, that inform posture control.

Signup and view all the flashcards

Proprioception

The body's ability to sense its position in space and movements.

Signup and view all the flashcards

Vestibular component of posture control

Part of posture control that relies on the balance system within the inner ear.

Signup and view all the flashcards

Maculae

Sensory structures in the vestibular system that detect linear acceleration and head position changes.

Signup and view all the flashcards

Otholites

Calcium carbonate crystals in the maculae that help sense gravity and movement.

Signup and view all the flashcards

Semicircular canals

Structures in the inner ear that provide information about rotational movements of the head.

Signup and view all the flashcards

Vestibular reflexes

Reflexes triggered by the vestibular system to maintain balance and posture.

Signup and view all the flashcards

Flexion and extension reflexes

Movements where flexion occurs in one limb while extension occurs in the opposite limb due to head movement.

Signup and view all the flashcards

Neck proprioceptive reflex

Reflexes triggered by neck movements that involve limb extensions and flexions.

Signup and view all the flashcards

Anticipatory Activation

Activation of muscles prior to a movement to ensure stability.

Signup and view all the flashcards

Feedforward Control

Muscular response based on expected movements, initiating posture adjustments before the action.

Signup and view all the flashcards

Feedback Control

Correction of movement based on sensory input during and after actions.

Signup and view all the flashcards

Gastrocnemius Response

Muscle reaction in the calf activated during postural adjustments.

Signup and view all the flashcards

Vestibular System

System providing spatial orientation and balance through gravity and acceleration information.

Signup and view all the flashcards

Visual System

Sensory system that provides information for posture through sight.

Signup and view all the flashcards

Muscle Spindles

Proprioceptors that provide information about muscle stretch.

Signup and view all the flashcards

Golgi Tendon Organ

Proprioceptor located in tendons that senses tension.

Signup and view all the flashcards

Joint Receptors

Proprioceptors located in joints signaling joint position and movement.

Signup and view all the flashcards

Spinal Component

Part of postural control that receives proprioceptive inputs through the spinal cord.

Signup and view all the flashcards

Anticipatory Postural Adjustments

Motor adjustments made in anticipation of movement.

Signup and view all the flashcards

Straightening Reactions

Postural adjustments that react to maintain balance during movement.

Signup and view all the flashcards

Midline Displacements

Movements that occur when maintaining posture amidst perturbations.

Signup and view all the flashcards

Stability Limits

The boundaries within which the body maintains stability without changing support.

Signup and view all the flashcards

Postural Stability

The ability to maintain body center of mass within stability limits.

Signup and view all the flashcards

Dual Task Performance

Executing cognitive tasks while moving, often challenging in older adults.

Signup and view all the flashcards

Center of Mass (CM)

The point in the body where mass is equally distributed, crucial for balance.

Signup and view all the flashcards

Quadrupedal Stability

Balance maintained using four limbs based on the center of mass.

Signup and view all the flashcards

Bipedal Stability

Balance maintained on two limbs, narrower stability limits than quadrupedal.

Signup and view all the flashcards

Antigravitary Muscles

Muscles that counteract gravity to maintain an upright posture.

Signup and view all the flashcards

Postural Control System

The network that keeps the center of mass within supporting limits.

Signup and view all the flashcards

Changing Environments

The ability to function well while adapting to surroundings.

Signup and view all the flashcards

Study Notes

Postural Control

  • Posture is a complex process involving both voluntary movement and automatic activities, such as locomotion, to maintain balance in both static and dynamic situations
  • Posture is defined as an actively maintained, stable body orientation in space and relative to its segments over an extended period
  • Posture depends on anatomy (evolution of the skeleton), muscle activation, and the independence of upper limbs
  • Posture maintains a stable position in relation to gravity using egocentric, exocentric, and geocentric coordinates
  • The brain uses these coordinates to ensure limb balance

Postural Control Aims

  • Maintain correct body segment alignment
  • Maintain correct body-environment relationships
  • Establish upright posture (adjusts for gravity), essential for activities like walking
  • Create a reference framework for perception and action in relation to the external environment

Stability

  • Stability limits define the area of space where the body can maintain its position without altering the base of support
  • Stability limits are not fixed; they depend on the task, individual, and the environment's characteristics (horizontal or oblique planes)
  • The center of mass (CM) location within the stability area dictates the stability in quadrupedal and bipedal postures
  • Humans maintain posture by keeping CM in a limited, smaller, upright area between their feet

Neural Components in Postural Control

  • Sensory inputs (visual, vestibular, proprioception)
    • Proprioception: senses the position and movement from muscle spindles, tendons, and joints
    • Vestibular system: helps maintain balance based on head position and movement
    • Visual system: provides visual feedback for postural control
  • Spinal component: receives sensory inputs and coordinates muscle actions for posture control
    • Reflexes (e.g., stretch reflex)
    • Muscle synergies for maintaining posture
  • Role of different sensory inputs
    • The nervous system processes sensory inputs to maintain upright posture
  • Brain/brainstem structures involved in postural control
    • Cortex, cerebellum, reticular formation, and extrapyramidal system

Postural Control and Reflexes

  • Spinal reflexes (e.g., stretch reflex, tonic neck reflexes, crossed extensor reflex, straightening reactions, placing reactions) are essential for postural control
    • Stretch reflex: responds to muscle stretch to maintain posture
    • Tonic neck reflexes: respond to head position to adjust posture, these are essential for development
  • Asymmetric tonic reflexes: asymmetrical adjustments, as head rotation leads to opposing postural adjustments in the opposite limb
  • Symmetric tonic reflexes: symmetric adjustments (respond to head position affecting two limbs), these are essential for development
  • Role of visual and vestibular systems: compensatory mechanisms or feedback adjustments to maintain balance by processing information from sensory systems

Components of Postural Control

  • Vestibular: maintaining balance. The vestibular system maintains posture through linear and angular acceleration. Its role is crucial for posture when dealing with changing environments and faster, more complex, movements
  • Visual: information from retinal pathways. The visual system helps with postural adjustments and compensating for postural disturbances
  • Sensory inputs, feedback and forward control. Sensory inputs affect postural control by providing data on the body position in space and relative to other parts.

Additional Points

  • Posture is essential for various daily activities, including mobility, and dexterity, and it is influenced by factors such as age, disease, and the environment
  • Age-related changes can cause a decline in postural control
  • Impaired postural control can lead to falls and other mobility problems
  • Posture is a crucial factor that affects the ability of someone to perform daily tasks, and it can be assessed through different tasks to study the integrity of the postural control responses

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Physio 18 - Postural Control PDF

Description

This quiz explores the intricacies of postural control and stability. It covers the definitions, mechanisms, and aims of maintaining posture in various environments. Test your understanding of how the brain coordinates body alignment and balance.

More Like This

Postural Control Quiz
5 questions

Postural Control Quiz

rawa° avatar
rawa°
Postural Control and Muscle Function Quiz
48 questions

Postural Control and Muscle Function Quiz

FeatureRichJasper2188 avatar
FeatureRichJasper2188
Postural Control Overview
5 questions

Postural Control Overview

NavigableJadeite1784 avatar
NavigableJadeite1784
Use Quizgecko on...
Browser
Open
Browser
Browser