2 Flashcards
Classifying skills
Domain: Cognitive, perceptual and motor
Characteristics: This is used to analyze a skill, and its important to note that characteristics are on a continuum
Environmental predictability- open and closed skills
Type of muscle used- fine and gross muscles
Initiation of movement- forced paced and self paced
Task organization- continuous, discrete or serial
Importance of physical or cognitive performance
Information processing model
Stimulus- Perception mechanism- decision mechanism- effector mechanism- action
Limited capacity
The human brain has a limited capacity for information. if too much information is presented, it results in overwhelming the person.
Information either gets filtered out or lots.
Speed accuracy trade off
Is an example of limited capacity.
A skilled performer has a higher accuracy in the same speed compared to an unskilled performer.
A skilled performer has a higher accuracy and speed compared to an unskilled performer and that is due to their increased information processing capacity. They have now moved that into their long term memory, and it has freed up some space which is automation.
That freed up space can be used for other things including thinking ahead and strategizing, also anticipating their opponents moves.
Now this automation is result of increase time dedicated to practice and it is also only specific to that certain task and it is not transferable.
Response time
Is the sum of all the time that it takes for each stage in the information processing model.
It is important to note that each stage of this model has to be trained separately in order to increase their processing time.
Limiting principle
Is this principle that by only looking at the end result of an action, you are not able to figure out the reason for successful or unsuccessful performance.
Attention residue
Is when the thoughts of a previous task residue the new task at work. It takes around 15 min for an individual to be focused on their task.
Performance and learning
Learning is a relatively permeant change in performance as a result of practice and training.
Performance is an observable behaviour.
Measuring performance
You can measure performance in two ways:
1. Either by looking at the outcome- which is the final goal
2. Or by looking at the production- which is the performance to achieve the goal
Now sometimes, the outcome is measured by the production. And so in this case, the outcome and production are synonymous. Including gymnastics, diving and etc.
Assessing production
It is hard to measure production but it is important to measure it because it affects our outcome.
- Human Judgment: This is a good method until a certain point. When the performance is fast and more complex, then it becomes a problem.
- Video recording: With this, you are able to go back, and slow down the video. Also, it reduces the memory capacity
- Fast analytical video recording: With this, you are able to analyze the video and computerize the performance.
- EMG: Record the electrical activity within our muscles
- Brain activity: We can measure EEG (electrical activity within different parts of the brain) and fMRI (which is the blood flow to different parts of the brain).
Assessing outcome
- Response magnitude- which refers to the absolute size of response
- Error/accuracy
Measuring error
- Constant error (CE):
You measure the mean
Response bias and direction error - Variability error (VE), standard deviation:
Measures the variability of performance
where 68% of our scores fall - Total variability (E):
The best type of performance outcome measure
It takes into account both constant error and variability error - Absolute error (AE):
It ignores the negative sign
Gives a general indication of the magnitude of error across all trials.
Reaction time Movement time Premotor time Motor time Response Time
Reaction time: the time from the appearance of stimulus until initiation of movement (PRMOT + MOT)
Movement time: The time from the initiation of movement till completion
Premotor time: The time before the EMG singling.
Motor time: The time from the initiation of EMG singling until the initiation of movement.
Response Time: movement time and reaction time
Information processing stages
Stimulus, perceptual mechanism, decision mechanism, effector mechanism and lastly action
Selective attention
Our information processing capacity is very limited. Therefore, we need to be very selective in what we pay attention to and that is selective attention.
Selective attention is a process that helps us tune out non important stimuli while helps us pay more attention to important stimuli. this helps us cope in a world full of stimuli.
Types of selective attention
Endogenous- We have control over this, we choose to not pay attention to certain things and it is controlled by our pre frontal cortex.
Exogenous- We do not have control over this and it is controlled by our environment and it takes place in the parietal cortex.
Visual selective attention
We are visual creatures and that means 80-90% of our information about the world gets to us through our eyes. The way we can measure this visual attention is by recording our eye movements.
In order for us to process a visual sense, we need to look at the object.
Concepts about vision
- Fixation
- Foveal- this is a narrow 2-5 mm that the image needs to be placed here for the information to be processed.
- Saccade- is the rapid eye movement which does not allow for the processing to occur
- The way we see is a mixture of fixation and saccade
- Pursuit eye movement- is when your eyes are fixated on a moving object, the eye matches the objects velocity
What do the arrows in the information processing model tell us?
They tell us about the flow of information which could mean refer to the processing that occurs in the CNS or the stimuli that is perceived by us and acted upon for a response.
What do the boxes in the information processing model tell us?
The boxes represent the stages of information processing. In each of those stages (boxes), information is further processed and passed down.
What do the feedback in the information processing model tell us?
The feedbacks represent errors- so that is the difference between what was supposed to happen and what actually happened.
RAS (reticular activating system)
RAS is located in our brainstem and more specifically the hindbrain
It determines what information will make its way to the brain and what does not
Inattention blindness
Is a type of selective attention
This happens when you are highly paying attention to one thing but then you miss something else
Peripheral vision
Peripheral vision is when an object is not within the foveal of the eye and so you are able to know that an object is there but you cannot determine the colour, details and the shape.
Auditory selective attention
Auditory selective attention has a limited capacity for processing information and also, it cannot process things simultaneously.
Divided attention: When you switch between ears
Selective attention: When you pick an ear and stick to that
Dichotic paradigm
Dichotic paradigm is when you have different sounds coming to different ears.
Inattentional deafness
When you cannot hear a sound because you are too focused on something else.
That is why, collision signals in cars use tactile signals where there is vibration of the wheel because that is the most effective way for capturing attention.
Inattentional deafness
When you cannot hear a sound because you are too focused on something else.
That is why, collision signals in cars use tactile signals where there is vibration of the wheel because that is the most effective way for capturing attention.
Perception
Is a sensory stage in which determines if a stimulus is present or not and if it is what is it?
Neuroanatomy of vision (retina, fovea and optic nerve)
Retina- is at the back of the eye and it receives information/stimulus about the environment. It is made up of cons and bipolar neurons
Fovea- is a narrow dense part in the back of the eye full of rods and cons in which image is seen with the most clarity
Optic nerve- after the retina has received the information, with the help of the optic nerve, the information is sent towards the brain.
Oculomotor system
Oculomotor system are the eye muscles that control the movement of the eye. They place the image on the fovea so that it can be clearly seen and processed
Visual information pathway
- Information hits the retina (cons and bipolar neurons)
- Information travels with the help of optic nerve (axons)
- Optic nerve takes the information to optic chiasma where decussation occurs.
- After optic chiasma, is where optic tract starts and takes the information with the help of radiations to the LGN (thalamus)
- The information is then sent to occipital lobe
Vestibule-ocular reflex
Vestibule-ocular reflex is how we fixate on an image while our head is moving. Now this is possible because our eyes move in the opposite direction of the head movement with the help of information from semicircular canals in our ears and the superior colliculus.
Visual streams
When information is sent to the occipital lobe, it splits it into a motor control and object recognition. Dorsal stream - back - posterior parietal lobe - Guides movements relative to objects
Vental stream
- Front
- Temporal lobe
- Object recognition
Optic chiasma
Is where splitting of visual information happens. This splitting only occurs on the nasal side and not the temporal side.
During optic chiasma, 90% of the information is sent to the LGN via optic tract. 10% of the information is sent to the superior colliculus via optic tract.
Lateral geniculate nucleus (LGN)
LGN is located within thalamus and it is the relay station. The visual information need to pass this in order to get to the brain for processing.
Optic nerve vs optic tract
Optic nerve is in the periphery just before the optic chiasma. But optic tract is in the central nervous system, right after optic chiasma.
This indicates that the dividing line between the periphery and central would be optic chiasma.
Superior colliculus
After decussation, 10% of information vis optic tract is sent to Superior colliculus. from here, the information is sent to the brainstem where it controls eye movement.
Damage to dorsal stream- posterior parietal lobe
action
Dorsal stream guides movement relative to objects. concerned with immediate actin upon an object.
concerned with selecting action to particular spatial location. unconscious
Optic ataxia
Problems pointing to or grasping objects but no problem with recognition
Damage to ventral stream- temporal lobe
recognition
Concerned with conscious perception and recognition of objects.
The ventral stream, commonly referred as the “what”
stream, is involved in the recognition, identification and categorization of visual stimuli.
Visual agnosia
Problems recognizing or naming objects but no problem reaching out and grasping objects
Proprioception and kinesthesis
Proprioception: Is the sense of the relative position of our body part within space.
Kinesthesis: Awarness of our limbs and body motion through space.
Proprioception and Kinesthesis enables us to be aware of our body and motion even though we cannot see it.
Muscle definition
Extrafusal and intrafusal fibres
Muscles are made up of variety of fibres different in size and function
Extrafusal fibres- They are the big in size and are responsible for contraction of muscle. They are located on the outside of the muscle and innervated by alpha motor neurons
Intrafusal fibres: They are the muscle spindles responsible for proprioception. They sense the change in length and the rate of this change in length. They are innervated by gamma motor neurons.
Sensory neuron fibres are wound tightly around these intrafusal/muscle spindles.
They send feedback to the CNS whether muscle is static or dynamic via sensory neuron fibres. They protect us from overstitching or stretching too fast.
Also, intrafusal fibres are in parallel with extrafusal fibres
Types of intrafusal fibres
Nuclear bag (dynamic and static)- Their cell bodies are budged in the middle of the fibre Nuclear chain (static)- Their cell bodies are spread out
Types of afferent (sensory neurons) fibres
Type Ia- this connects to nuclear chain and nuclear bag fibres. It provides information regarding the change in length, velocity of change during static and dynamic situations.
Type Ib- This is related to Golgi tendon organ (GTO), and provides information regarding changes in tension
Type II- It connects to nuclear chain fibres (static) and nuclear bag fibres (static) and provides positive sense of muscle when it is static.
Gamma motor neurons
They innervate the intrafusal fibres. Their responsibility is to adjust the sensitivity of the muscle spindles by taking up the ends and pulling it so it is stretched again (this is when the muscle contracts, resulting in the spindle becoming slack).
Golgi tendon organ
It is innervated with sensory neuron Ib which it senses tension within the tendons. This is useful for preventing injury due to excessive exertion of force.
They are placed in series compared to parallel.
GTO is activated when the tendon is stretched which causes an increase discharge of GTO.
And they do not get activated based on passive movements.
When there is an increase in tension, the GTO sends a signal via sensory neuron (Ib) and synapses with an inhibitory interneuron in the CNS (spinal cord) which then inhibits a motor neuron and it results in a reduction in tension.
Reflexes
Stretch reflex: Involves the Ia innervating the alpha motor neuron of the same muscle
Withdrawal reflex: It is a spinal reflex intended to protect the body from damaging stimuli
They are quick, require a stimulus, involuntary and stereotypic
Vestibular system
Sends information to the brain when head moves.
It helps us know where we are in space when we are moving
Provides a sense of balance and information about body position that allows rapid compensatory movements in response to both self induced and externally generated forces
Alpha motor neurons
They innervate the extrafusal fibres and their role is to help with contraction of the muscle.
Stretch reflex
Is a muscle contraction in response to stretching within the muscle. When there is an increased stretch of an agonist muscle, sensory signals are sent to the CNS where two motor neurons are sent back. One inhibitory motor neuron is sent to the agonist muscle while an excitatory motor neuron is sent to the antagonist muscle.
Withdrawal reflex
The withdrawal reflex is a spinal reflex intended to protect the body from damaging stimuli.
When you touch something hot, the sensory neurons sent a signal to the CNS and a motor neuron is immediately sent back singling for withdrawal.
Flexor crossed extensor reflex
When you step on something sharp, your sensory neurons will stimulate multiple interneurons.
Ipsilateral motor neurons to flexor muscle causes withdrawal
Contralateral motor neurons to extensor muscle causes support
Reciprocal inhibition
Causes a muscle to automatically relax when a muscle that is adjacent to it contracts.
This co contraction prevents the effects of unexpected external forces.
Joint receptors
Signal extreme ranges of movement
Cutaneous receptors
Measure skin deformations
Used in balance, object manipulation
Vestibular system
Receives information when the head moves
it helps us etc know where we are in space and how we are moving
balance, muscle tone, postural control, spatial orientation, alertness, and eye movement
provides the sense of balance and the information about body position that allows rapid compensatory movement in response to both self induced and externally generated forces.
inner ear- brainstem- thalamus and cortex- interprets input provides spatial orientation
inner ear- brainstem- brainstem- steadies eyes during body motion
inner ear- brainstem- spinal cord- influences muscle tone and posture adjustments
inner ear- brainstem- cerebellum- coordination of movement of eyes, head and body
