White matter pathways Flashcards
Three major types of white matter pathways
Projection fibres
Association fibres
Commisural fibres
Fibres which connect higher and lower centres of the brain
Projection fibres
Fibres which connect different regions within the same hemisphere of the brain
Association fibres
Fibres which connect similar regions of opposite hemispheres
Commisural fibres
Largest bundle of fibres which connect the two cerebral hemispheres
Corpus callosum
Fibres which connect the two olfactory bulbs
Anterior commisure
Fibres which connect the two hemispheres of the midbrain
Posterior commisure
Fibres which connect the posterior dorsal thalamic nuclei
Hippocampal commisure
Habenular commisure
Most posterior part of the corpus callosum
Splenium
Features of disruption to the splenium
Alexia
Inability to name colours
Preserved ability to copy words
White matter tract that connects the hippocampus to the hypothalamus
Fornix
White matter tract that connects Broca’s and Wernicke’s areas
Arcuate fasciculus
Features of damage to the arcuate fasciculus
Conduction aphasia - inability to repeat words
Type of tract the corticospinal tract is
Projection
Function of the corticospinal tract
Efferent tract that connects the motor cortex to the brain stem and spinal cord
Type of tract the corticobulbar tract is
Projection
Function of the corticobulbar tract
Efferent tract that connects the cranial nerve motor centres to the brain stem and spinal cord
Two tracts that make up the pyramidal tracts
Corticospinal
Corticobulbar
Type of tract the corona radiata is
Projection tract
Function of the corona radiata
Connects the cortical areas to the internal capsule
Type of tract the geniculocalcarine tract (optic radiatum) is
Projection
Function of the geniculocalcarine tract
Connects the lateral geniculate nucleus to the primary visual cortex
Type of tract the corpus callosum is
Commissural
Type of tract the cingulum is
Association
Function of the cingulum
Connects the frontal, parietal and temporal lobes
Type of tract the superior occipitofrontal fasciculus is
Association
Function of the superior occipitofrontal fasciculus
Connects the occipital and frontal lobes
Type of tract the inferior occipitofrontal fasciculus is
Association
Function of the inferior occipitofrontal fasciculus
Connects the occipital and frontal lobes
Type of tract the uncinate fasciculus is
Association
Function of the uncinate fasciculus
Connects parts of the frontal lobe to the anterior temporal lobe
Tract which connects the frontal lobe and temporal lobe of the same hemisphere
Superior longitudinal/arcuate fasciculus
Pathway which connects the cerebral cortex to the medulla oblongata and is primarily involved with motor function of the cranial nerves
Corticobulbar tract
Pathway which connects the cerebral cortex to the spinal cord and is primarily involved with motor function of the limbs and trunk
Corticospinal tract
Function of the dorsal column medial lemniscus pathway
Conveys sensations of fine touch, proprioception and vibration from the body to the brain
Tract which originates in the red nucleus and plays a role in the tone of limb muscles and fine movements
Rubrospinal tract
Tract which originates from the pons and facilitates voluntary movements
Medial reticulospinal tract
Tract which originates from the medulla and inhibits voluntary movement
Lateral reticulospinal tract
Tracts which originate from the vestibular nuclei and control balance and posture
Vestibulospinal tracts
Tract which originates in the superior colliculus and coordinates movements in the head in response to visual stimuli
Tectospinal tract
Tract which conveys the sensations of crude touch and pressure
Anterior spinothalamic tract
Tract which conveys the sensations of pain and temperature
Lateral spinothalamic tract
Tracts which carry unconscious proprioceptive information to the cerebellum for the control of posture and coordination of movement
Spinocerebellar tracts