18.2.1 Forebrain Neuroanatomy Flashcards
Cerebrum
Gray matter
Cell bodies
White matter
Axons
Cerebral cortex
Outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain
Frontal lobe
Frontal lobe
Frontal lobe functions
- Conscious movement of the body (M1)
- Reward
- Attention
- STM tasks
- Goals
- Prioritisation
Damage to frontal lobe
Problems with memory, behavioural changes and reduced ability to plan
Temporal lobe
Temporal lobe
Temporal lobe functions
- Decoding visual and auditory input into meanings for retention
- Language comprehension
Damage to temporal lobe
- Aphasia
- Reduced hearing
- Memory impairment
Parietal lobe
Functions of the parietal lobe
- S1; processing sensory information
- Left side; language, maths, interpreting signals
Damage to the parietal lobe
- Sensory deficits; numbness, difficulty perceiving/localising input
- Cognitive deficits in attention, problem-solving
Occipital lobe
Occipital lobe
Occipital lobe functions
- Visual processing
Damage to occipital lobe GRT
Problems with vision
Insular lobe (insula)
Insula
Insula
Insula
Functions of the insula
- Taste
- Emotion
- Vestibular
Insula
Damage to the insular
- Apathy
- Loss of libido
- Inability to tell fresh food from rotten
Limbic lobe
Gyrus
Ridge on the surface of the brain, increasing its surface area and surrounded by sulci
Precentral gyrus
In which lobe is the precentral gyrus
Frontal
Precentral gyrus function
Primary motor cortex (M1); initiation and control of voluntary motor movements
Homunculus of the precentral gyrus
Face laterally and legs/feet medially
Lesion to precentral gyrus
Contralateral loss/weakness of voluntary motor function
Postcentral gyrus
In which lobe is the postcentral gyrus?
Parietal
Postcentral gyrus function
Primary somatosensory cortex (S1); processing somatosensory information like touch, pressure, temperature and pain
Homunculus of the postcentral gyrus
Face laterally and legs/feet medially
Lesion to the postcentral gyrus
Contralateral sensory deficit
Hippocampus
Hippocampus
Yellow
Dentate gyrus
In which lobe is the dentate gyrus?
Temporal
Gyrus capable of neurogenesis
Dentate gyrus
Dentate gyrus functions
- Formation of new memories
- Pattern separation
Lesions of the dentate gyrus
- Memory deficits
Orange
Parahippocampal gyrus
In which lobe is the parahippocampal gyrus?
Limbic/medial temporal
11
Parahippocampal gyrus
Parahippocampal gyrus
Blue
Uncus of parahippocampal gyrus
Lesion to the parahippocampal gyrus
Deficits in memory and spatial navigation
Cingulate gyrus
Structure 4
Cingulate gyrus
Which structures project to the cingulate gyrus? (2)
- Hippocampus
- Ventral anterior and ventral lateral nuclei of thalamus
In which lobe is the cingulate gyrus?
Limbic
Cingulate gyrus functions
- Emotional processing
- Pain perception
In which lobe is the superior temporal gyrus?
Temporal
Superior temporal gyrus function
- Primary auditory cortex
- Speech (Wernicke’s area)
Superior temporal gyrus
Concerning the cerebral cortex and its connections, what function is associated with the superior temporal gyrus?
Speech
Lesion of left superior temporal gyrus
- Receptive aphasia
- Deficit in processing sound
Orbitofrontal gyrus
Orbitofrontal gyrus functions
- Decision making
- Emotional processing
- Social behaviour
Lesions to orbitofrontal gyrus
Impulsivity, inappropriate social behaviour and difficulty regulating emotions
Wernicke’s area
Effects of a lesion to Wernicke’s area
Receptive (sensory) aphasia
Function associated with Wernicke’s area
Language comprehension
Broca’s area
Effects of a lesion to Broca’s area
Motor/expressive aphasia
Function associated with Broca’s area
Speech production
Primary visual cortex (V1)
Site of V1
Banks of post-calcarine sulcus
3
Primary visual cortex (V1)
3
Primary visual cortex (V1)
Sulcus
Ridge between gyri
Longitudinal sulcus
Longitudinal sulcus divides
Two cerebral hemispheres along the saggital plane
Central sulcus
Central sulcus divides
- Frontal and parietal lobes
- M1 and S1
Lateral sulcus
Lateral sulcus divides
Frontal and temporal lobes
Parieto-occipital sulcus
Calcarine sulcus
Calcarine sulcus divides
Occipital lobe into superior and inferior halves
Cingulate sulcus
Cingulate sulcus divides
Frontal and parietal lobes from cingulate gyrus
Tract
Bundle of axons grouped together with similar origin, destination and function
3 main tracts of forebrain
- Internal capsule
- Optic radiations
- Cerebral peduncles
Internal capsule
Internal capsule
5 and 6 show
Anterior and posterior limbs of the internal capsule
5 shows
Internal capsule
Internal capsule fibres run where
Ascending and descending fibres running between the cerebral cortex and the brainstem/spinal cord
Origin of internal capsule fibres
Cerebral cortex