Physiology
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Physiology - Marcador
Physiology - Detalles
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| According to the "National Statement on Ethical Conduct in Human Research", the general principles of research conduct include: | Research Merit and Integrity Justice Beneficence Respect |
| What is the research merit and integrity aspect of the values and principles of ethical conduct? | The level of merit which can be achieved through the conduction of the research, the integrity of the researchers conducting the research, and the justification of ethical human involvement in the research. |
| What is the Justice aspect of the values and principles of ethical conduct? | A fair distribution of the benefits of participation in research |
| What is the Beneficence aspect of the values and principles of ethical conduct? | Considering a participant's welfare and doing or producing good. |
| What is the Respect aspect of the values and principles of ethical conduct? | Values human autonomy and requires researchers to respect welfare, beliefs, perceptions, customs, cultural heritage of participants as well as their privacy, confidentiality and cultural sensitivities. |
| Define Null Hypothesis | The hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error. |
| Define Alternative Hypothesis | The alternative hypothesis is what the researcher might believe to be true or hope to prove true. |
| What is standard deviation? | Measures the amount of variation or dispersion of a set of sample data around the mean. |
| What is a P-value? | A P-value indicates the strength of the data and determines the significance of the results by testing the validity of the null hypothesis. |
| What does a small P-value (P<0.05) indicate? | A small P-value indicates that there is a statistically significant difference between groups, which provides strong evidence to reject the null hypothesis. |
| What does a large P-value (P>0.05) indicate? | A large P-value indicates the null hypothesis cannot be rejected because there is no significant difference between groups. |
| Define a Two-way ANOVA | A Two-way ANOVA is used to determine how a response is influenced by two factors. |
| Define Pearsons Correlation? | Pearsons Correlation is used when you want to determine the relationship between two continuous variables, (e.g. if HR and BP are related). |
| What is the difference between T-test (Unpaired) and T-test (Paired)? | An unpaired t-test compares the means of two independent or unrelated groups (e.g. diabetic vs healthy patients). A paired t-test is designed to compare the means of the same group or item under two separate scenarios (e.g. same subjects before and after drug treatment). |
| What is the difference between an One-Way ANOVA and a One-Way ANOVA (repeated measures)? | The one-way analysis of variance (ANOVA) is used to determine whether there are any statistically significant differences between the means of three or more independent (unrelated) groups. (e.g. Blood glucose in patients that are healthy, diabetic and diabetic +drug) A One-Way ANOVA (repeated measures) utilizes the same subjects over multiple tests to determine whether three or more group means are different. (e.g. blood glucose in patients before and after treatment of drug A and drug B) |
| What is power in statistics? | Power represents the number or fraction of experiments in which you will find a statistically significant difference. An experiment with high power will have a high chance of finding a statistical difference where there is one. |
| What are the different types of statistical error? | Type 1 Errors - occurs when a null hypothesis that is actually true is rejected, due to differences occurring by chance (i.e. false-positive) Type 2 Errors - occurs when a false null hypothesis is accepted, caused by random sampling of data (i.e. false-negative). |
| Define voluntary movement | Voluntary movements are consciously coordinated thoughts that are generated into action: Reflexive – can be carried out automatically without conscious control, and even with descending command signals disconnected. Rhythmic – can be performed without conscious voluntary control of all aspects of the movement, but subject to modification by feedback or voluntary commands, e.g., walking, breathing. Voluntary – Voluntary movements are goal-directed and improve with practice as a result of feedback and feedforward mechanisms. |
| How is voluntary movement controlled by the Central Nervous System? | Neurons in the motor cortex, the region of the brain that controls voluntary movement through: Cerebral cortex and descending pathways - receive input |
| Define Somatotopy | Somatotopy is the mapping of the body's surface sensations onto a structure of the brain |
| Explain somatotopic organisation of the Nervous System | Sensory pathways use the information carried by a number of anatomically distinct pathways, where each part of the pathway projects in an orderly fashion, creating topographic maps. |
| What is the difference between Somatosensory Cortex and Posteriori Parietal Cortex? | Somatosensory Cortex – provides sensory information required for specific planning, initiation and ongoing movement. Posterior parietal cortex – encodes complex sensory information (visual, auditory or somatosensory) to ensure planned movement is matched to the external environment. |
| Define Phantom Limb Sensation | Phantom limb sensation is a condition where sensory neurons can adapt due to amputation. |
| Describe the role of sensory and motor cortical areas in movement control | Primary motor cortex (M1, area 4) – controls simple features of movement Premotor cortex (area 6 lateral) – involved with planning and coordination of movement in response to sensory outputs and important for multi-joint coordination Supplementary motor area (area 6 medial) – active during the planning of coordinating of internally guided movements and involved in bimanual coordination. Voluntary movements are organised in the cortex, where the primary motor cortex controls simple features of movement The premotor and supplementary motor areas are involved in planning complex movements |
| Define the process of plasticity | The connections in the brain can be modified by experience or injury |
| Describe how the nervous system is organized | The nervous system is structurally composed of: The Central Nervous System and Peripheral Nervous system CNS - consists of the brain and spinal cord PNS - composed of the ganglia (group of neurons) and efferent/afferent nerve fibers that relay signals between the CNS and other parts of the body. |
| Define the major functions of the CNS | Subconsiouly regulates our internal environment through neural means Allows the exeprience of emotions controls voluntary movement Controls perception, allowing you to conciously be aware of the body and it's surroundings Engages in cognititve process such as thought and memory |
| Define major functions of the PNS | Afferent division: detetcs, encodes and transmits peripheral signals to the CNS Afferent input: used to plan for voluntary actions and infrom centres of the CNS controlling homeostasis Efferent division: trasnsmits signals from CNS that control the activities of effector organs (e.g. msucles and glands) |
| State the major steps of the process of scientific theory | Observation: observe natural phenomenon and come up with question Hypothesis: propose an explanation of the phenomenon with the limited evidence provided as a starting point for further investigation Experiment: test the hypithesis and collect data Analysis: analyse the data collected Conclusion: draw a conclusion supported by the data, which can adjust the hypothesis or be used to design a new hypothesis Application: the result of the expiment e.g. new drug, treatment etc. |
| Describe the characteristics of Myotonia Congenita | Muscle stiffness and delayed relaxation (generally painless) upon intitial activity Unusual exertion asscoiated with muscle hypertrophy (increased muscle mass) Myotonia Congenita can be hereditary in an autosomal dominant (e.g. Thomsen Disease) OR recessive (e.g. Becker Disease). Myotonia Congenita can be caused by poisoning from certain weedkillers. |
| Describe the symptoms of Myotonia Congenita | Myotonia Congenita is a symptom of cerain neuromuscular disorders with symtoms characterised by: The slow relaxation of muscles after voluntary contraction or electrical stimulation Note: Repeated effort is needed to relax muscles and the condition impoves once muscles have warmed up |
| Explain the molecular bases for dominant and recessive forms of Myotonia Congenita | A313T mutation that causes dominant myotonia congenita shifts open probability of the channels to positive potentials by ~120 mV All mutations causing dominant form of disease shift Po to positive potentials Chemicals that induce myotonia in skeletal muscle (2,4-D; CPP) also shift Po to positive potentials All nonsense mutations and some missense mutations can cause recessive myotonia |
| Briefly describe the role of Cl channels in skeletal muscle action potential | Depolarisation phase (excitation) - Na+ and Ca2+ channels open, letting Na +and Ca2+ ions into the cell Repolarisation phase (recovery from excitation) – K+ and Cl-open, letting K+ ions out and Cl-ions into the cell Skeletal muscle cells have high Cl conductance due to a large number f Cl channels on the plasma membrane ( 80% of total membrane conductance at rest) Increased excitability of the muscle can be caused by an increase in Na+ and/or Ca2+ conductance, or by a decrease in K+ and/or Cl-conductance Myotonia can be induced by blocking Cl-conductance by at least 60-70% |
| Explain the role of the membrane as a barrier with selective permeability | The phospholipids are tightly packed together, and the membrane has a hydrophobic interior which causes the membrane to be selectively permeable. A membrane that has selective permeability allows certain molecules (lipid soluble) and block other molecules (large polar molecules) from moving freely though the cell membrane. |
| Describe the role of facilitated diffusion (uniporter) in regulating cell function | Transported molecule binds to a specific binding site on a carrier exposed to one side of the membrane. Binding results in in a conformational change of the carrier protein which exposes transported molecule to the other side of the membrane. The rate of the carrier-mediated transport is much slower, compared to the passage of ions through an ion channel pore. |
| Describe the role of primary active transport (pumps) in regulating cell function | In primary active transport, the carrier splits ATP to move a substance against its concentration gradient. Energy in the form of ATP is required to vary the affinity of the binding site when it is exposed on opposite sides of the plasma membrane. |
| Describe the role of secondary active transport (cotransporters) in regulating cell function | In secondary active transport, the carrier does not directly split ATP. Instead, it utilises the potential energy in the Na+ gradient. Movement of Na+ into the cell down its concentration gradient drives the uphill transport of another solute by a secondary active-transport carrier. |
| Describe the role of secondary active transport (counter transporters) in regulating cell function | Counter-transporters utilise the same mechanism of transport as cotransporters but the solute and Na+ move through the membrane in opposite directions. |
| Describe the role of Potassium (K+) ion channels in regulating cell function | K+ channels function to restore and maintain a resting membrane potential K+ “leak” channels are active at rest and maintain negative resting membrane potential |
| Describe the role of Sodium (Na+) ion channels in regulating cell function | Na+ channels cause excitatory responses Voltage gated Nav channels open rapidly in response to membrane depolarisation. Na+ entering the cell through Nav channels cause further membrane depolarization (positive feedback loop in action potential) |
| Describe the role of Calcium (Ca2+) ion channels in regulating cell function | Ca2+is an important second messenger, coupling stimuli to responses Voltage-gated Ca2+channels open in response to membrane depolarization, contributing to action potentials in neurons and cardiac muscle |
| Explain the ionic basis of the resting membrane potential | Ions are electrically charged chemical forces which move down the concentration gradient. The direction of ion movement across the plasma membrane depends on: concentration gradient and voltage gradient (membrane potential) In order for memebrane potential to be establidhed there must be: Symmetric distribution of ions across the plasmamembrane (i.e., ion concentration gradients) Selective ion channels in the plasma membrane. |
| Define osmosis and osmotic pressure | Osmosis: the flow of warer molecules through a semipermiable memerbane from a region of high solute concetration, until equilibrium is esablished Osomotic Pressure: pressure required to counter osmosis. |
| Define equilibrium potential | Equilibrium potential occurs when: The chemical and electrical gradients for an ion are equal in magnitude, the ion is in electrochemical Equilibrium, and the net movement of this ion species across the membrane is zero. |
| State the equilibrium potential of Na+ and K+ | At resting membrane potential K+, Na+ and Ca2+ ions are not at equilibrium |
| Explain the significance of the Nernst Equation | The Nernst Equation states that at equilibrium the chemical gradient and the electrical gradient of an ion species are equal in magnitude and opposite in direction |
| Explain the action potential as a sequence of changes in driving force and permeability | Permeability is a measure of how easily an ion can cross the membrane. It depends on the number of open channels and the number of ions passing through each channel. |
| Explain the significance of the Goldman Hodgkin Katz (GHK) equation | When more than one ion channel is present in the membrane, the membrane potential can be calculated using the Goldman-Hodgkin-Katz equation (GHK equation): |
| Describe negative and positive feedback loops in action potential | Positive feedback loop: membrane depolarisation opens more Na+ channels and accelerates further depolarisation (Ensures fast excitation) Negative feedback loop: membrane depolarisation opens more K+ channels which slows down depolarisation and promotes membrane repolarisation (Ensures recovery from excitation) |
| Describe the all-or-nothing law of action potentials | V threshold – membrane potential that opens voltage gated Na+ channels Hyperpolarising and subthreshold depolarising stimuli cause graded changes in membrane potential Depolarising stimuli of any amplitude above the threshold cause identical action potentials |
| State the effects of Tetrodotoxin (TTX) blockers on the amplitude and duration of the action potential | TTX is a poison produced by symbiotic bacteria that blocks the pore of the voltage-gated Na+ channels It is found in species such as blue ringed octopus and puffer fish. |
| State the effects of Tetraethylammonium (TEA) blockers on the amplitude and duration of the action potential | TEA is a blocker of voltage gated KV channels |
| State the effects of Tetraethylammonium blockers on the amplitude and duration of the action potential | KV channels blockers increase the duration of action potentials With all KV channels blocked, only Na V channels inactivation allows the downstroke of AP. No hyperpolarization (undershoot) occurs. |
| State the effects of local anesthetics (LA) on the amplitude and duration of the action potential | Local anaesthetics cross the lipid bilayer in an uncharged form and bind to the intracellular part of the Na V channels in the inactivated state LA creates an absence of pain sensation in a specific location of the body |
| Describe the structure of a neuron | Dendrites: receive incoming chemical signals and convert them into graded potentials Cell body (soma): integrates graded potentials coming from dendrites Axon terminals: release chemical messengers that simultaneously influence numerous other cells through synapses. Axon hillock: area of high expression of NaV channels and action potential initiation Axon: carry electrical signals such as action potentials from the cell body to the end of the axon. |
| Explain the concept of threshold depolarization and self-regenerative action potentials | Threshold depolorisation: the state at which a neuron will fire an action potential (approximately -55mV) Self-regenerative action potentials: action potentials are regenerate at the unmyelinated nodes of Ranvier due to the triggering of graded depolorisation which opens Na+ voltage dependent channels, resulting in more Na+ entering the cell. |
| Explain the roles of glial cells, myelin sheath and nodes of Ranvier | Glial cells maintain homeostasis and form myelin in the CNS and also protect neurons, however they DO NOT carry nerve impulses (action potentials) Myelin sheath are fatty tissue sleeves that protect nerve cells and increases the speed of signals transmitted between neurons (action potentials). Nodes of Ranvier facilitate the rapid conduction of nerve impulses |
| Define Saltatory conduction | Depolarisation propagates passively from one node of Ranvier to the next, where the action potential is regenerated The action potential amplitude is maintained over long distances by repeating boosting the signal to full height using the energy in the Na+ gradient, at regularly spaced nodes. |
| Define types of refractory periods | Absolute refractory period: a second stimulus (no matter how strong) will not excite the neuron Relative refractory period: a stronger than normal stimulus is needed to elicit neuronal excitation |
| Explain the significance of Na+ channel inactivation in an axon | Because Voltage-gated sodium channels play an important role in action potentials, it's crucial for these channels to assume a closed-inactivated state as it results in the refractory period and is critical for propagation of action potentials down the axon. |
| Describe the structural domains of neurons that allow signal integration and conduction of action potentials | Excitatory synapse – binding of a neurotransmitter to the receptor-channel results in the opening of nonselective cation channels in the postsynaptic membrane that permit simultaneous passage of Na+ and K +ions Excitatory Postsynpatic Potential (EPSP) – small depolarization of the postsynaptic neuron. Inhibitory synapse – binding of a neurotransmitter with its receptor-channels opens either K+ or Cl- channels in the postsynaptic membrane Inhibitory Postsynpatic Potential (IPSP) – small hyperpolarization of the postsynaptic neuron |
| Define Neuromuscular Junction | Neuromuscular junctions are specialized chemical synapse between motor neuron and skeletal muscle fibre. |
| Describe pre-synaptic sequence of events | When the action potential arrives at the synaptic terminal it results in presynaptic depolorisation which causes: Activation of voltage-gates Ca2+ Channels (located near active zones) Ca2+ enters terminal (the amount of Ca2+ that enters the terminal is dependent upon the amplitude and shape of the action potential) |
| Describe post-synaptic sequence of events | Transmitter binds at postsynaptic receptors. Bound receptors regulate ion conductance. Transmitter is cleared by diffusion, enzymatic breakdown, or transport (re-uptake) back into the presynaptic terminal or glia. |
| What is the quantal hypothesis? | The quantal hypothesis is a statistical procedure that isolates the mechanistic components of synaptic transmition and their modification by utilising the quantal release of neurotransmitters into the synapse via vesicles called 'quanta'. |
| What are the mechanisms for the removal of neurotransmitters? | Diffusion – suitable for lipid-soluble neurotransmitters (diffusive process basically wait for the neurotransmitter to wander away) Degradation – breaks down neurotransmitters Reuptake – directly recycles neurotransmitters in the synapse |
| Explain the neurotransmission at the skeletal muscle endplate is fast, direct and always excitatory | Presynaptic response to skeletal muscle: Skeletal muscle cells express a single type of receptor in the endplate, nAChR channels, in high density (high safety factor) Endplate potential dysfunction is related to: Myasthenia gravis–an autoimmune disease Muscle EPPs in myasthenia gravis lack the safety factor, leading to weakness of voluntary muscles Neostigmine and other inhibitors of ACh esterase are used to treat patients with myasthenia gravis. |
| Describe the role of postsynaptic responses in neurons which allow integration of excitatory and inhibitory information | Most neurons receive thousands of synaptic inputs Single synaptic inputs in neurons are small (0.5 –5 mV) Multiple inputs are required to reach threshold Threshold is reached through temporal and spatial summation of single postsynaptic potentials |
| Describe the role of neuronal postsynaptic receptors which allow integration of excitatory and inhibitory information | Ligand-gated channels produce responses that are fast and localized. The same channel that detects the transmitter creates the ion current. G-protein-coupled receptor responses are relatively slower, smaller, longer in duration, and rely on separate ion channels in the membrane. |
| Describe the role of activated or inhibited ion channels which allow integration of excitatory and inhibitory information | Ligand gated channels create responses that last for 10 –100 milliseconds GPCR responses can last for seconds, minutes or hours Activation of the same GPCRs in different cell types may have opposite effects |
| Describe the role of temporal summation in neurons which allow integration of excitatory and inhibitory information | Temporal summation can occur because postsynaptic potentials last longer than action potentials. |
| Describe the role of spatial summation in neurons which allow integration of excitatory and inhibitory information | In spatial summation multiple postsynaptic potentials from different synapses occur about the same time |
| Define sensory perception | Sensory perception is our conscious interpretation of the external world as created by the brain from the pattern of nerve impulses delivered to it by sensory receptors. |
| Describe the attributes of a sensory stimulus | Modality: The form of energy transformed into sensation (the type of stimulus). Intensity: The strength of the stimulus, at or above a threshold level. Duration: The length of time that the stimulus persists. Location: The position of stimulus input. |
| Describe the different sensory receptors and sensory modalities | Mechanoreceptors – touch, pressure, vibration, stretch, hearing Thermoreceptors – temperature change Photoreceptors – light Chemoreceptors – taste, smell, oxygen and carbon dioxide Osmoreceptors – osmotic pressure of body fluids Nociceptors – pain (fast pricking pain, slow burning pain and heat/cold) |
| Explain modality in regards to sensory information and coding of sensory stimuli | Receptors respond to specific types of stimuli "Labelled line” - receptors of a certain modality transmit their information to specific subsets of neurons on the way to the cortex Some pathways are non-specific (polymodal) due to convergence of inputs from receptors of different modalities. |
| Explain intensity in regards to sensory information and coding of sensory stimuli | Frequency-coding of action potentials Recruitment of additional sensory units by larger stimuli Higher concentrations of neurotransmitter in the synaptic cleft produce larger receptor potentials in the second order neuron |
| Explain location in regards to sensory information and coding of sensory stimuli | Receptive fields Discrimination of stimuli by size, number and overlap of receptive fields “Map strategy” organization of sensory pathways |
| What is the role of the nerves in processing of visuals, auditory OR tactile information? | Nerves are bundled tracts of axons, which carry signals from receptive fields throughout the body to spinal cord or brainstem. |
| What is the role of the dermatomes in processing of visuals, auditory OR tactile information? | Dermatomes are areas of the skin that are supplied by a single spinal nerve, they help relay sensory, motor and autonomic information between the rest of the body and the CNS. |
| What is the role of the retina in processing of visuals, auditory OR tactile information? | The retina is a layer of nervous tissue that covers the back two-third of the eyeball stimulating light so that the sensation of vision can be initiated. |
| What is the role of the cochlea in processing of visuals, auditory OR tactile information? | The external and middle portions of the ear transmit sound waves to the fluid-filled inner ear, amplifying sound energy in the process. Mechanoreceptors in cochlea convert sound waves into action potentials, making hearing possible. |
| Define 'sensory homunculus" | The sensory homunculus is the sensory fields of the body that are mapped in the parietal cortex in a pattern. Body parts of sensory homunculus are proportional to the amount of cerebral cortex devoted to a given body region and to how richly that region is innervated. |
| Define 'retinotopic map' | The retinotopic map is the visual field of the retina is mapped in the occipital cortex. |
| Define 'tonotopic map' | The tonotopic map is the way the auditory cortex is organized, which includes properties such as: Frequency of tones Frequency ratios between harmonics and the pitch of complex sounds Speed and direction of frequency sweeps Sound intensity and location of sound in space |
| Explain the excitation-contraction coupling process | Excitation-contraction coupling refers to a series of events linking muscle excitation (the presence of an action potential in a muscle fibre) to muscle contraction (cross-bridge activity that causes the thin filaments to slide close together to produce muscle shortening). |
| Describe the cell contraction sequence | Impulse reaches axon’s synaptic knob Synaptic vesicles fuse with neurons from the membrane and release ACH via exocytosis. ACh binds to receptors on sarcolemma. Sodium channels open, allowing sodium to flow in. If enough sodium moves into the muscle cell, an impulse (action potential) develops. |
| Describe the function of skeletal muscle with an emphasis on muscle contraction | Contractile force is produced by the interaction of the thick and thin filaments. The interaction of actin and myosin produces muscle contraction. Calcium (tropomyosin) - Covers actin sites blocking interaction that leads to muscle contraction. Calcium (troponin) – with the absence of tropomyosin, actin and myosin bind, interact at cross bridges, resulting in muscle contraction. The thin filaments slide over the thick filaments during muscle contraction, but the filaments themselves don’t change length. This results in a shorter I and H band, but the A band does not change. |
| Describe the structure of skeletal muscle | Muscle consists of several muscle fibres lying parallel to one another and held together by connective tissue Single skeletal muscle cell is known as a muscle fibre (10-100 microns) Myofibrils -contractile elements of muscle fibre – About 1 micron in diameter (one-millionth of a meter) The appearance of striations – Displays alternating dark (the A bands) and light bands (the I bands) Sarcomere – functional unit of skeletal muscle (2 μm wide) and found between two Z lines (connects thin filaments of two adjoining sarcomeres) |
| Describe the neural factors that contribute to changes in muscle force | Neural factors involve the ability of the nervous system to modulate muscle force by varying the number of activate motor units (recruitment) and the rate at which they discharge action potential (rate coding). Recruitment - number of muscle fibres contracting within a muscle Rate of modulation - twitch summation of each contracting fibre by increasing rate of action potentials (rate modulation) |
| Differentiate between the different types of rates of modulation | Single twitch – muscle fibre is restimulated after it has completely relaxed (the second twitch is the same magnitude as the first) Twitch summation – muscle fibre is restimulated before it has completely relaxed (the second twitch is added on to the first twitch, resulting in summation) Tetanus – muscle fibre is stimulated so rapidly that it does not have an opportunity to relax at all between stimuli (maximal sustained contraction) |
| Describe the muscular factors that contribute to changes in muscle force | Muscular factors involve differences in muscle size, muscle fibre type, muscle fibre length and the velocity of shortening. The maximum force that a muscle can exert depends on the Physiological cross-sectional area (PCSA). (PCSA) – measure of the number of cross-bridge that are in parallel. Muscles with large PCSA produce large forces but have short muscle fibres and lower contractile velocity. |
| Describe the mechanical factors that contribute to changes in muscle force | Mechanical factors are determined by the origin and insertion of muscle on bones to generate torque (Formula: Torque = Force x Length of power arm) |
| How does muscle size/muscle fibre type (mechanical factor) contribute to changes in muscle force | Fast-twitch – high force and fast fatigue Fast-twitch – moderate force and fatigue resistant Slow-twitch – low force and fatigue |
| How does muscle fibre length (mechanical factor) contribute to changes in muscle force | The length-tension relationship shows that the force that a muscle fibre can exert varies with the degree of overlap between the thick and thin filaments. |
| How does the velocity of shortening (mechanical factor) contribute to changes in muscle force | The force that a muscle fibre can exert varies with the velocity of the contraction. The variation in force is mainly due to the time it takes for cross-bridges to produce force (concentric) and detachment of cross-bridges (lengthening). |
| How does muscle torque (mechanical factor) contribute to changes in muscle force | The action of a muscle about a joint depends on the torque that it exerts Formula: Torque (Nm) = Force (N) x power or load arm (m) |
| Explain 'feed-forward control' and describe its mechanism | Feed-forward control – used during rapid movements and anticipatory postural adjustments e.g. volleyball. Utilises anticipatory postural adjustments - performing a rapid movement like raising one arm which requires CNS activity to compensate for the off-balance activity that movement would produce. |
| Explain 'feed backward control' and describe it's mechanism | Feedback control – involves the sensory receptors providing information on the changes that occur, which modifies the command signals to accommodate the change in the Controlled System, e.g. when a ball strikes the hand. |
| What role do visual receptors (eyes) play in improving motor performance? | Visual receptors provide information that enables execution of motor performance through knowledge of environmental cues, aiding in direction. Kinesthetic sense - when movements can be performed without relying on vision |