Networks in brain and motor learning

Implicit motor learning is

procedural, develops slowly, requires repetition, impacted by very little instructions

Explicit motor learning is

declarative, can occur in motor tasks, results in knowledge, largely impacted by specific instructions and repetition

Learning of a task happens best when

the difficulty matches the learner’s skill level and the complexity of the environment

As the task difficulty increases

immediate performance decreases due to challenge

Learning of a task requires

variability in the taks and feedback (implicit or explicit)

In PT, the benefits of “goal based exercise” are

activities to improve performance via neuroplasticity in a supervised environment

Stepping/gait training needs principles of

specificity, repetition, and intensity of motor training

Examples of high intensity training

stepping/gait training, interval training, circuit training

How can we create hight intensity during gait

stance control, limb advancement, propulsion, postural stability

Stance Control

absence of vertical limb or trunk collapse during stance

Limb Advancement

adequate foot clearance and positive step length BL

Propulsion

ability to move center of mass in specific limb advancement

Postural Stability

maintaining upright in sagittal and frontal planes, keeping center of mass within BOS

Motor priming

simulus prompts a change in behavior

Stimulation based priming

repetitive transcranial magnetic stimulation, transcranial direct current stimulation, peripheral electrical nerve stimulation

Motor imagery/action observation

mirror therapy, video directed, audio directed, therapist demonstrated

Movement based priming

repetitive movements: active or passive, unilateral or BL, aerobic exercise

Pharmacological based priming

amphetamines, dopaminergic agents, norepinepinephrine

Ways to measure intensity levels

Cardiovascular intensity, Rate of percieved exertion, rate of perceived stability, success vs error rate

Cardiovascular intensity

HR max

Rate of perceived exertion

scale of how much you are working

Rate of perceived stability

scale of how stable you feel

Functions of the diffuse modulatroy networks

These networks are used for system activation in the motor control model for neuromodulation. Analogous to car radio controls for different settings

Common features of the different systems of the modulatory networks

Small sets of neurons are at the core of each system, they arise from the central core of the brain, typically brainstem, the axons from each neuron contact over 100,000 postsynaptic neurons, some release NTs into the extracellular fluid to diffuse multiple neurons postsynaptically

Noradrenergic System releases which neurotransmitter

norepinephrine

Noradrenergic System is involved in the regulation of

cognitive functions, attention, arousal, sleep/wake cycle, learning/memory, anxiety/emotions, pain, mood, and brain metabolism

What activation system is used for the arousal of the forebrain

ascending reticular activation system

Locus coeruleus to

entire cerebral cortex, thalamus, cerebellum, and SC (50% of all noradrenergic neurons) and is best activated by new, unexpected, non

What are the only nonadrenergic neurons that innervate the cerebral cortex

the LC neurons

When is the nonadrenergic system most active

when something “interesting” happens externally

Serotonergic system releases which neurotransmitter

serotonin

In the Serotonergic system the neurons are located in the

9 raphe nuclei in brainstem

Medullary nuclei projects to

the spinal cord project to modulated pain related sensory signals

Pons/midbrain nuclei projects to

the rest of brain

The serotonergic system is most active during

wakefullness and activity

Part of the ascending reticular activiating system is for arousal of forebrain but it is also involved in

control of mood and emotional behavior, and perception of pain

Drugs like LSD act as an

agonist to the raphe receptors, decreasing firing rates of this system, and also acting as an agonist to the cerebral receptors

What system when distorted makes you hallucinate and form perceptions of things that don’t exist

serotonergic system

Dopaminergic system releases which neurotransmitter

dopamine

Two closely related groups of DA cells are part of the diffuse modulatory systems

Substantia nigra to striatum and VTA (ventral tegmentum areas) of midbrain to frontal cortex and limbic system

Substantia nigra to striatum

facilitates and initiation of voluntary motor responses to environmental changes

VTA (ventral tegmentum areas) of midbrain to frontal cortex and limbic system

prolongs the effect os NE and DA to intensify the experience, while also reinforcing the reward system

Drug stimulants like cocaine and amphetamines work to

block catecholamine reuptake mechanism

Cholinergic system releases which neurotransmitter

acetylcholine

What are the two networks of the cholinergic system

basal forebrain complex and pontomensecephalo tegmental complex

Basal forebrain complex

neurons are scattered into several medial and ventral pathways to the BG

What are the first cells to die in alzimers

the cells from the basal forebrain complex

Pontomesencephalo

tegmental complex to dorsal thalamus

The cholinergic system controls

Controls selective attention of activities and cognitive processing speed, Hallmarks of AD, PD, and Lewy

Connectome project

Neuro research funded over the last few decades that looks to construct a map of the complete structural and functional neural connections in individuals

Resting brain networks are

default network

The importance of distributed functional networks and synchronized activity within between networks to

mediat cognitive functions

Coherent activity in large scale brain networks occurs

not only during task performance but even when at rest

Sense of self

distracts EF of brain from working, allows your wandering mind and daydreaming of your internal exploration

Medial prefrontal cortex

Imagining, thinking about yourself, figuring out what others may think, recognizing that you have a different belief system than others