Identify the brain structure indicated by the blue arrow in the following image:
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Options:
explanation: The image shows an axial view of the brain cut at the level of the diencephalon and the insular lobe, as well as the levels of the third ventricle and the occipital horns of the lateral ventricles. The interhemispheric fissure is in the midline, with the frontal lobes at the top of the image and the splenium of the corpus callosum anterior to the occipital lobes (bottom of the image). The blue arrow indicates the putamen, which is the lateral-most nucleus of the basal ganglia, a component of the striatum together with the caudate nucleus. It lies lateral to the globus pallidus externus and posterior to the head of the caudate nucleus.
name: Putamen
label: a
answer: yes
explanation: The image shows an axial view of the brain cut at the level of the diencephalon and the insular lobe, as well as the levels of the third ventricle and the occipital horns of the lateral ventricles. The interhemispheric fissure is in the midline, with the frontal lobes at the top of the image and the splenium of the corpus callosum anterior to the occipital lobes (bottom of the image). The globus pallidus internus is the medial segment of the globus pallidus, which is the innermost component of the basal ganglia, visible in the image medial to the structure indicated by the arrow. Thus, the blue arrow indicates the putamen, which is the lateral-most nucleus of the basal ganglia, a component of the striatum together with the caudate nucleus. It lies lateral to the globus pallidus externus and posterior to the head of the caudate nucleus.
name: Globus pallidus internus
label: b
answer: no
explanation: The image shows an axial view of the brain cut at the level of the diencephalon and the insular lobe, as well as the levels of the third ventricle and the occipital horns of the lateral ventricles. The interhemispheric fissure is in the midline, with the frontal lobes at the top of the image and the splenium of the corpus callosum anterior to the occipital lobes (bottom of the image). The caudate nucleus is the most extensive component of the basal ganglia, with a head, body and tail enclosing the thalamus and the other basal ganglia nuclei. It forms part of the striatum, together with the structure indicated by the arrow. However, the blue arrow indicates the putamen, which is the lateral-most nucleus of the basal ganglia, a component of the striatum together with the caudate nucleus. It lies lateral to the globus pallidus externus and posterior to the head of the caudate nucleus.
name: Caudate
label: d
answer: no
explanation: The image shows an axial view of the brain cut at the level of the diencephalon and the insular lobe, as well as the levels of the third ventricle and the occipital horns of the lateral ventricles. The interhemispheric fissure is in the midline, with the frontal lobes at the top of the image and the splenium of the corpus callosum anterior to the occipital lobes (bottom of the image). The thalamus is the largest structure of the diencephalon, being the main relay station for sensory impulses traveling from the periphery to the central nervous system (except for olfactory signals). The thalamus is located posteromedial to the structure indicated by the arrow. However, the blue arrow indicates the putamen, which is the lateral-most nucleus of the basal ganglia, a component of the striatum together with the caudate nucleus. It lies lateral to the globus pallidus externus and posterior to the head of the caudate nucleus.
name: Thalamus
label: e
answer: no
explanation: The image shows an axial view of the brain cut at the level of the diencephalon and the insular lobe, as well as the levels of the third ventricle and the occipital horns of the lateral ventricles. The interhemispheric fissure is in the midline, with the frontal lobes at the top of the image and the splenium of the corpus callosum anterior to the occipital lobes (bottom of the image). The globus pallidus externus is the lateral segment of the globus pallidus, which is the innermost component of the basal ganglia, visible in the image medial to the structure indicated by the arrow. Thus, the blue arrow indicates the putamen, which is the lateral-most nucleus of the basal ganglia, a component of the striatum together with the caudate nucleus. It lies lateral to the globus pallidus externus and posterior to the head of the caudate nucleus.
name: Globus pallidus externus
label: c
answer: no

Correct answer: a