9: Integrated Functions (CNS) Flashcards
Central Nervous System: Integrated Functions
Automatic patterned response to a stimulus
Reflex
Classification of reflexes (4)
- Spinal or cranial
- Somatic or autonomic
- Innate (inborn) or conditioned (learned)
- Monosynaptic or polysynaptic
The type of reflex that is involve in signals sent via SOMATIC NEURONS to SKELETAL MUSCLES
Somatic reflexes
The type of reflex that is involve in signals sent via AUTONOMIC NEURONS to SMOOTH MUSCLE, CARDIAC MUSCLES OR GLANDS
Autonomic reflex (visceral reflex)
The type of reflex that consists of only two neurons and a single synapse
Monosynaptic reflex
The type of reflex that consists of more than two neurons and multiple synapses
Polysynaptic reflex
Neuronal pathways for reflexes
Reflex arcs
Five components of a reflex arc
- Sensory receptor
- Afferent neuron
- Integration center
- Efferent neurons
- Effector organ
Muscle spindle stretch reflex
Stretch reflex
Where is interneuron found?
only in CNS
Only neurons that could control skeletal muscles
motor neurons
Neurons that take command from the brain and carry the message to the skeletal muscles
Efferent neurons
Two descending pathways
- Pyramidal tract neurons
2. Extrapyramidal tract neurons
Axons of neurons in the pyramidal tracts terminate in the ventral horn of spinal cord
Upper motor neurons
- Type of a motor neuron tract that controls voluntary movement of the distal extremities.
- Originates in primary motor cortex
Pyramidal tract
Contralateral side in an area of medulla
medullary pyramids
- Type of motor neuron tract that oncludes all motor pathways outside pyramidal tracts
Extrapyramidal tract
- Type of motor neuron tract that is responsible for posture and balance
Extrapyramidal tract
The simultaneous transmission of the same general type of information along separate neural pathways
Parallel processing
Three nuclei in the brainstem
- Reticular formation
- Vestibular nuclei
- Red nuclei
The part of the brain that exerts involuntary control over posture
Brainstem
The part of the brain that formulates the plan of action and commands the muscles to execute them
Cortex
- Part of the brain that compares the actual movements as they are occurring with the plans, making corrections in the force and direction of movement whenever detects discrepancy
- also acts as the “guidance system”
Cerebellum
Part of the brain that receives information about the status of a movement from sensory areas of the cortex, basal nuclei, brainstem and spinal cord. It then transmits information to the cortex via the thalamus enabling the cortex to alter its output to modify movement.
Cerebellum
Disease caused by impaired/damaged basal nuclei
Parkinson’s Disease
Part of the motor control that provides feedback to the cortex for the development of motor strategies and smoothing out of movements
Basal nuclei
Part of the motor control that receive input from the cortex –> send output back to the cortex via the thalamus
Basal nuclei
A cyclically occurring state of decreased motor activity and perception.
Sleep
- (Sleep) characterized by multiple stages of low frequency waves in the EEG
- Brain activity decreases, but parasympathetic nervous system increases
Slow Wave Sleep (SWS)
- (Sleep) Characterized by high-frequency waves in the EEG
- Brain activity increases during this
Rapid Eye Movement (REM)
States of depressed activity in the central nervous system
Anesthesia and coma
- A diffused network of nuclei which is critical in maintaining alert wakefulness.
- Information to the cortex –> thalamus, hypothalamus and forebrain, which awakens the cortex
Ascending Reticular Activating System of the Brainstem (ARAS)
3 Neurotransmitters associated with awake state
- Acetylcholine
- Norepinephrine
- Dopamine
4 Parts of the brain involved in the Ascending Reticular Activating System (ARAS) of the brainstem
- Midbrain
- Pons
- Reticular formation
- Medulla
Integrate thoughts, memory and sensory information and communicate to the limbic system
Cortical association areas
The system that “creates” the emotion. This system communicates the emotion to the hypothalamus for a response.
The Limbic System
Part of the limbic system that is responsible for bodily responses coupled with the emotion such as hormonal changes motor responses and autonomic responses.
Hypothalamus
5 CNS Structures involved in emotions
- Amygdala
- Hypothalamus
- Midbrain
- Limbic System
- Cerebral cortex
A structure in the limbic system that is responsible for fear and anxiety.
Amygdala
A structure in the limbic system that is involved in anger and aggression.
Hypothalamus
The impulse that drives our actions
Motivation
Motivation can be these 2 things:
- Physiological
2. Emotional
- A strong motivating emotion.
- contains dopamine
- can be addictive
Pleasure
Neurotransmitters that motor neurons release
Acetylcholine
