9 - Gross anatomy of the brain I Flashcards
What are gyri?
Ridges of brain
What are sulci?
Small folds in the brain
What are the main folds and fissures in the brain?
- longitudinal cerebral fissure
- central sulcus
- lateral sulcus
How are grey and white mater organised in the brain?
White mater is enclosed by grey mater - white on the inside
What is the overall function of the cerebrum?
- cerebral cortex controls higher brain activity
- memory, intelligence, personality
- interpretation of impulses
- initiation of voluntary movement
What are the lobes of the cerebrum?
- frontal
- temporal
- parietal
- occipital
- insula
Where is the insula located?
Deep to frontal, parietal and temporal
What divides the hemispheres of the cerebrum?
Falx cerebri
What are folia?
Ridges of the cerebellum
Where is the cerebellum located?
- posterior to medulla, pons and midbrain
- inferior to cerebrum
- lies in posterior cranial fossa
What connects the hemispheres of the cerebrum?
corpus collosum
What connects the hemispheres of the cerebellum?
Vermis
What is the function of the cerebellum?
controls balance on the ipsilateral side of the body
What makes up the brainstem?
- medulla
- pons
- midbrain
Where is the midbrain located?
Junction of anterior/posterior cranial fossi
What makes up the diencephalon?
- epithalamus
- hypothalamus
- thalamus
Where is the medulla located?
- continuous with spinal cord
- posterior cranial fossa
Where is the pons located?
- forms bridge between medulla and midbrain
- anterior part of posterior cranial fossa
What CN are associated with the midbrain?
- CN III
- CN IV
What CN are associated with the medulla?
- CN IX
- CN X
- CN XII
What CN are associated with the pons?
CN V
What CN arise between the junction of the pons and medulla?
- CN VI
- CN VII
- CN VIII
What is another name for the insula?
limbic system
What is contained in the insula?
- hypocampus
- fornix
- amygdala
How are the frontal and parietal lobes separated?
Central sulcus
How are the parietal and occipital lobes separated?
Parieto-occipital sulcus (medial side)
How are the temporal, parietal and frontal lobes separated?
Lateral sulcus
What are the different areas of the frontal lobe?
- prefrontal cortex
- motor cortex
- broca’s area
Describe the prefrontal cortex.
- most anterior
- problem solving, complex planning and decision making, personality
- depth of feeling, judgement, initiative
- coordinates all association areas
Describe the somatic motor association area.
- premotor cortex
- anterior to primary motor cortex
- learned movements
What is a cortical association area?
An area that coordinates motor responses or interprets sensory information.
Describe the primary motor cortex.
- pre central gyrus
- control of voluntary movement
- specific areas of the gyrus map to specific body parts
Describe Broca’s area.
- motor speech area
- production of speech
- usually found in the left hemisphere (ie the dominant hemisphere)
- regulates breathing patterns when speaking
- coordinates muscles to produce correct sounds
What is broca’s aphasia?
Patients can comprehend words but not form them themselves (speech and writing)
What are the different areas in the parietal lobe?
- primary somatosensory cortex
- sensory association area (posterior parietal cortex)
Describe the primary somatosensory cortex.
- postcentral gyrus
- tactile sensation
- conscious perception of pain, temperature, vibrations, taste, touch etc
Describe the posterior parietal cortex.
- interpretation of the sensory information
- spatial perception
- cognitive function
- ability to recognise objects without having seen them (ie feel with hands)
What is the homunculus?
- map of the body to the gyrus
- motor and sensory
- size relates to degree of fine motor skill or sensory feedback
What are the different areas of the occipital lobe?
- visual cortex
- visual association area
Describe the primary visual cortex.
- located at the calcarine sulcus
- receives visual information from the thalamus
- conscious perception of visual information
- right field of vision is represented in the LHS of brain
Describe the visual association area.
- relates information from visual cortex to previous experiences
What are the different areas of the temporal lobe?
- auditory cortex
- auditory association area
- Wernicke’s area
- temporal cortex
Describe the auditory cortex.
Perception of sounds including words, pitch and tone
Describe Wernicke’s area.
- language comprehension
- found in dominant hemisphere
- important to personality
What is Wernicke’s aphasia?
- can form words but in meaningless sentences
- rhyming words are often used
- understanding of what words mean is lost
What connects Wercnike’s and Broca’s area?
Arcuate fasciculus
Describe the auditory association area.
- recognition of words
- memory related to grammar and vocabulary
What is the function of the insula?
- anterior involved in language (planning and coordination)
- posterior involved in integrating information regrading pain
- connected to olfactory cortex and gustatory
- cardiovascular homeostasis
- emotional and empathic response
