Brain systems video Flashcards
What is a functional brian system?
Networks of neurons that work together and span wide areas of the brain
- Limbic system
- Reticular formation
What is the limbic system?
- Structures on the medial aspects of cerebral hemispheres and diencephalon
- Includes parts of the diencephalon and some cerebral structures that encircle the brain stem
What do the amygdala and cingulate gryus do?
- Amygdala-recognizes angry or fearful facial expressions, assesses danger, and elicits the fear response
- Cingulate gyrus-plays a role in expressing emotions via gestures, and resolves mental conflict
Why does limbic system interact with prefrontal lobes?
- We can react emotionally to things we consciously understand to be happening
- We are consciously aware of emotional richness in our lives
What is role of hippocampus?
Play a role in emotional memory.
What are the main functions of the limbic system?
The limbic system is involved with processing and experiencing emotions.
What is reticular formation system?
- Projects vertically through core of midbrain, pons, and medulla
- Loosely organized core of gray matter
- Motor component
- communicates with spinal cord
- responsible for regulating muscle tone
- assists in autonomic motor functions, e.g., heart rate
- connects hippocampus with other diencephalon limbic system
Sensory component, termed reticular activating system (RAS) - alerts sensory components to reticular activating system
- contains sensory axons projecting to cerebral cortex
- processes visual, auditory, and touch stimuli
- uses information to keep us alert
- not active during sleep
What is Consciousness?
- Includes awareness of sensation and voluntary motor activities
- Involves simultaneous activity of large areas of cortex
- Exists on a continuum from alertness to sleep
- during sleep, cortical activity depressed
- functions continuing in brainstem
What does RAS do?
- Sends impulses to the cerebral cortex to keep it conscious and alert
- Filters out repetitive and weak stimuli (~99% of all stimuli!)
- Severe injury results in permanent
unconsciousness (coma)
What are the levels of Consciousness?
Clinically defined on a continuum that grades behavior in response to stimuli
- Alertness
- Drowsiness (lethargy)
- Stupor
- Coma
How is the reticular activating system related to the reticular formation?
The reticular activating system is the sensory component of the reticular formation, responsible for alerting the cerebrum to incoming sensory information.
What is higher order of mental functions?
Higher-order mental functions
- Include learning, memory, and reasoning
- Occur within the cortex of cerebrum
- Involve multiple brain regions
- Both conscious and unconscious processing involved
What are characteritsic of memory?
Storage and retrieval of information
* Two stages of storage
- Short-term memory (STM, or working memory)-temporary holding of information; limited to seven or eight pieces of information
- Long-term memory (LTM) has limitless capacity
What are brain regions involed in langauge?
Includes functions of reading, writing, speaking, and understanding
Wernicke area
* involved in interpreting writing and oral language
* in the categorical hemisphere in most people
Broca area, motor speech area
* receive axons from Wernicke area
* regulates motor activities needed for speech
* sends signals to primary motor cortex
- innervate muscles of cheeks, larynx, lips, and tongue
Angular gyrus
* posterior to Wernicke area
* processes words read into speakable form
How is the Wernicke area involved in language processing?
The Wernicke area is involved in interpreting what we read and hear. It sends speech plans to the motor speech area.
