Task 1- Brain Anatomy Flashcards
Anterior/ Rostral
Towards the nose end
Posterior/Caudal
Towards the tail end
Dorsal
Towards the back or top of the head
Ventral
Towards the chest or bottom of the head
Medial
Towards the middle
Lateral
Away from the middle
Inferior
Lower or Below
Superior
Upper or above
CNS
-brain and spinal cord
-‘central’ because: - combines info from entire body
and coordinates activity across the whole organism
-most protected system, covered by 3 meninges and cerebrospinal fluid
Peripheral nervous system (PNS)
- all nerves that lie outside of CNS
- the role is to connect the CNS to organs limbs and skin
- PNS allows the brain and spinal cord to receive and send info to other areas of the body
- Two divisions: 1.Somatic Nervous system (SNS)
2. Automatic nervous system (ANS)
Somatic nervous system (SNS)
(one of PNS division)
part that interacts with the external environment
Automatic nervous system (ANS)
↳Sympathetic nerves
↳Parasympathtic nerves
(one of PNS division)
-a part in charge of regulating the body’s internal environment
∙Sympathetic nerves: project from CNS in lumbar and thoracic regions of the spinal cord
∙Parasympathetic nerves: project from the brain and sacral region of the spinal cord
Meninges
- Protective tissue/membranes of the brain
- Consists of 3 different layers
1. Dura mater
2. Arachnoid membrane
3. Pia mater
Meninges: 1.Dura mater
↳Falx
↳Tentorium
- Most outer layer; Thick and tough, Flexible but not stretchable
- Two special dural folds:
1. Falx: Separates the right and left hemispheres of the brain
2. Tentorium: Separates the cerebrum from the cerebellum
Meninges: 2.Arachnoid membrane
↳Subdural Space
-Middle layer; thin, web-like membrane that covers the entire brain; made of plastic tissue
↳Subdural space: Space between dura and arachnoid membranes
Meninges: 3.Pia mater
-Third layer; surrounds brain and spinal cord;
-has many blood vessels that reach deep into the brain
↳Subarachnoid space : Space between the arachnoid and pia mater; Filled with cerebrospinal fluid
function of Cerebrospinal fluid (CSF)
function:
1. protection: acts as a cushion in the brain, limits neural damage
2. Buoyancy: brains weight is reduced, prevents excessive pressure
3. Chemical stability’: creates an environment that allows proper functioning of the brain
‣takes oxygen out of the brain and sends whatever the brain doesn’t need to the blood
Ventricles; Ventricular System
- Set of 4 interconnected ventricles in the brain, where CSF is produced
- within each ventricle is a region of choroid plexus,
- responsible for the production, transport and removal of cerebrospinal fluid
Lateral ventricles (left and right)
- Located within their respective hemispheres of the cerebrum
- volume increases with age
Third ventricle
situated in between the right and left thalamus
fourth ventricle
it receives CSF from the third ventricle via the cerebral aqueduct
➝ from there the fluid drains into 2 places: central spinal canal and subarachnoid cisterns
Telencephalon
-frontal subdivision of forebrain
-largest part of the brain: composed of right and left hemispehres
-mediates brains most complex functions like: interpreting touch, vision and hearing,
speech, reasoning
emotions
learning and fine control of environment
corpus callosum (largest cerebral commisure)
the main band of axons that connects the two cerebral hemispheres
-transmits messages from one side to another
Right hemisphere
- Creativity, spatial ability, artistic/musical skills
- plays large part in interperting visual info and spatial processing
Left hemisphere
language and speech
comprehension
arithmetic and writing
dominant in hand use and language
(Cerebral) cortex
- tissue layer of hemispheres
- layer mainly composed of UNmyelinated (lack of myelina) and small neurons➝ Gray matter
- layer beneath is w/ myelinated neurons➝White
- foldings increase brain surface are =more neurons fit inside= enable higher function
Gyrus
Each fold
Sulcus
each wrinkle between folds
Neocortex
2
-90% of cortex is called neocortex
-Neurons are divided into 2 different type of cells:
↳Pyramidal cells
↳Stellate cells
(Neocortex)
Pyramidal cells
(3)
- large multipolar neurons
- pyramid-shaped bodies
- large dendrite that extends from apex of pyramid towards cortex surface
(Neocortex)
Stellate cells
small star shaped interneurons
↳neurons with small axon or without it
Columnar organization
neurons course vertically through neocortex
↳vertically flow of info
Hippocampus
4
-medial temporal lobe structure
-important for learning and memory, spatial awareness
-three major layers
-stabilization from short-term to long-term memory
➮In Alzeheimers diseasese, its first region to suffer damage (short-term memory loss and disorientaion)
Fissure
large wrinkles in cortex
Precentral gyri
3
motor strip
- largest gyri in frontal lobe
- situated in front of postcentral gyrus
Postcentral gyri
receives somatosensory info from body (receptive area for sense of touch
-partieal lobe
Superior temporal gyri
3
- perceptions of emotions in facial stimuli
- function of language, auditory processing
- temporal lobe
Cingulate gyrus
4
-processing emotions and behavior regulations
-autonomic motor function
-curved fold covering corpus callosum
-component of limbic system
➮ Damage to it: cognitive emotional behavioral disorders
Longitudinal fissure
Largest fissure
-Cerebral Commisures ➮ Hemispheres connecting tracts
Central fissure and Lateral fissure
divide each hemisphere in the 4 lobes
Frontal Lobe
6
- personality, behavior
- emotions, judgment
- planning, problem-solving
- Speech: Speaking and writing (Broca’s area)
- Body movement (motor strip)
- Intelligence concentration. self-awareness
Partial Lobe
Interprets language, words
Analyzes sensation from body such as touch, pain, temperature (sensory strip)
Occipital Lobe
interprets visual perceptions (color, light, movement)
visual input to guide our behavior
Temporal Lobe
3
- Superior temporal gyrus: hearing and Language (Wernicke’s area)
- Inferior temporal cortex: Identifying complex visual pattern
- Medial temporal cortex: certain kind of memory
Broca’s Area (Left frontal lobe)
If damaged: difficulties moving tongue or facial muscles to produce sound of speech
➝ we can still read and understand spoken language
‘Brocas Aphasia’ - Difficulty in speaking and writing forming letters and words
Wernicke’s Area (Left temporal lobe)
if damaged: ‘Wernicke’s Aphasia’
- speak in long sentence with no sense, create new words
- able to make speech sounds but not to understand it
Aphasia
disturbance of language affecting speech production, comprehension, reading or writing due to brain injury (stroke or trauma)
Limbic system
3
- centre of our emotions, learning and memory
- associated with regulation of motivated behavior (4 F’s: feeling, feeding, fighting, sex)
- consists of hippocampus, amygdala, fornix, cingulate cortex, mammillary body, septum
LS : Amygdala
4
-emotional reactions (fear, anxiety, aggression) memory, decision making
-located anterior temporal lobe
➮Responsible for emotional reactions of PTSD patients
➮Amygdala dysfunction is found in ppl with bipolar disorder
➮larger in male brain and sociopaths
Fornix
3
-Major tract of limbic system
-connects mammillary bodies and hippocampus
→Damge can cause difficulty in recalling long term info
Cingulate Cortex
2
-receives inputs from thalamus and neocortex
-involved with emotion formation and processing, learning and memory
➮important dissorders such as depression and schizophrenia
Mammillary body
3
- located on the undersurface of the brain ( part of diencephalon)
- acts as relay for impulses from amygdala and hippoc.
- altertness and memory formation
Septum
-in middline of brain, attached to corpus callosum
➮Damage: developmental disorders (vision difficulty, low muscle tone, hormonal problems, seizures, intellectual probs
Basal Ganglia
2
-group of forebrain nuclei ( work with cerebellum to coordinate fine motors - fingertips movem.)
-plays a role in voluntary motor responses (Damage: momement impaiments)
➮Parkinsons d.
➮Huntingtons d.
Diencephalon
2
coordinate muscle movements, maintain posture and balance
-consists of thalamus and hypothal.
Thalamus
-sort of communication centre, gets info from different lobes and gives it to other brain areas
Hypothalamus
4
-control of autonomic system
‣eating, sleeping, sexual behav.
‣regulate body temp., blood pressure, emotions
‣secrete hormones that control sex. devel. promote bone and muscle growth and respond to stress
Optic chiasm
optic nerves from each eye come together
Mesencephalon
Midbrain
2 division: Tectum Tegmentum
Tectum
3
Dorsal portion of midbrain
Superior colliculi : Anterior Part (visual)
Inferior c. : Posterior Part (auditory)
Metencephalon
subdivision of hindbrain that includes cerebellum and pons
Reticular formation
exerts some control over which sensory signals reach cerebellum and come to our conscious attention
Pons
4
- portion of metencephalon
- part of brainstem connecting midbrain to medulla
- breathing, communication between diffr parts of brain
- hearing, taste, balance
Cerebellum (4)
- important sensorimotor structure
- receives info from sensory system, spinal cord, ..
- regulates motor movement
- located back of the brain dorsal to pons
Myelencephalon = Medulla
3
- posterior part of the hindbrain
- plays a role in arousal
- various nuclei of reticular formation are involved in sleeping, attention, movement, muscle maintenance, respiratory reflexes
Brain stem
4
- consists of midbrain (mesencephalon), pons (metencephalon) medulla ( myelencephalon)
- provides the main motor and sensory distribution to face and neck via cranial nerves
- regulates sleep cycle, CNS, maintain consciousness
- regulate cardiac and respiratory function
- most primitive area
Brain functions (5)
- Processing info (determines if info irrelevant or important
- sending signals ( neurons, signal passed on by substances = Neurotransmitters)
- Modules and connections (different parts do diffo things)
- Individuality
- Plasticity (brain tissue can be stregthend depending on how much we exercise it)
Which brain parts are essential for living?
7
- Medulla (breathing, heart rate; damage=death)
- Pons ( critical respiratory centers)
- Amygdala (sex, emotions- anger fear, mental condtion -> depression)
- Brainstem (digestion, heart rate)
- Hippocampus ( long.term memories, could not live in present)
- Thalamus (we would die or lose all our senses)
- Cerebellum (controls voluntary movements, language, memory, emotion)
How does damage to a particular area affect other parts?
-brain divided in 2 halves
-left half controls movement and sensation in the right side
and right half controls left side
