Cerebral Cortex II Flashcards
Part of brain that most deals with language and where, if there is an issue, it will likely occur
Left hemisphere around the sylvian fissure
Neurons are functionally arranged in…
Columns
Where is Wernicke’s area?
Superior temporal gyrus
Main path which lets Wernicke’s communicate to Broca’s
Arcuate Fasiculus
Affect of Broca’s area legion
(1) Non-fluent [telegraphic]
(2) Problems with repetition
(3) Can Understand
(4) Have issues saying the name of something
Affect of Wernicke’s area legion
(1) Fluent speech [can get sounds out]
(2) Poor repetition, naming and comprehension , as they don’t understand what’s going on.
Describe the reticular formation
- Very long (but stay in brainstem)
- Give a lot of dendrites which allow them to sample information which is going by them
- Coordinating system for many automatic functionings
The unique cytoarchitecture of the reticular formation allows for…
The convergence of somatosensory information and divergence of efferent outputs
Some of the unique functionings of the Reticular formation
(1) Sleeping/wakefulness
(2) Patten generator (chewing, sneezing, locomotion, etc.)
(3) Centers for resp/cardio/urinary control
(4) Pain (nociception)
3 major columns of reticular formation
(1) MIDLINE (RAPHE) ZONE- Secretes aminergic neurotransmitters
(2) PARAMEDIAN ZONE- Effector. Where fiber tracts and somatosensory information leaves RF.
(3) LATERAL ZONE- receive sensory information and sends to Paramedian
Reticular formation afferents come from…
Pretty much everywhere
Where do RF Efferents project/terminate?
Spinal cord and Brainstem
All the RF neurons in the midline use ________ as their transmitter
Serotonin
Serotonergic Projections of RF
Small collection of neurons with very broad effects. Alter large areas of the cortex, turning them on or off.
ARAS
Ascending Reticular Activating System
Plays a role in our level of alertness, sleep-wake rhythms and alerting (startle) reactions.
Plays role in consciousness
Nuclei which play important role in keeping you concious, and their associated neurotransmitters.
(1) Raphe nuclei- serotonin
(2) Locus ceruleus- norepinephrine
(3) Midbrain reticular formation (acetylcholine)
Super Chiasmatic Nucleus
Internal clock which is collaborated by light, hunger, temp. etc.
Clock mechanism helps produce sleep and certain types of sleep.
Turns some systems on and off.
Main potential roles for sleep
- Consolidation of memory and daily experiences
- Brain growth and development
- Restoration and Recovery
Characteristics of REM sleep
- No muscle tone
- Detailed, visual, emotional dreams
- Increased sympathetic. Irregular pulse and respiration
Characteristics of Non-REM sleep
- Decreased muscle tone
- Vague dreams
- Increased parasympathetic. Slow, regular pulse and respiration.
Physiological causes for the sleep cycle.
WE FALL ASLEEP BECAUSE- accumulation of certain chemicals in bloodstream or brain (ex. cytokines). This initiates set of reflexes and systems in brain stem which move you to sleep state.
WE GO NREM TO REM BECAUSE of additional neurons which transition us.
Main Structures involved with sleep.
Hypothalamus, thalamus, brainstem and basal forebrain.
All secrete neurotransmitter
Where are the neurons which secrete Orexin
Lateral Hypothalamus.
What is Orexin?
Helps to stabilize wake states and ensures that REM cycle system is turned off
Narcolepsy
- Orexin issue
- Automatic entrance to REM sleep
- Cataplexy- loss of connection between brain and spinal cord (like what happens to stop you for running when you’re asleep), except when awake
- Autoimmune
