Nutritional Neurosciences reader
Chapter 3. Gross and Functional Anatomy of Cognition (cognitive
neuroscience)
Neuroanatomy = the study of the nervous system’s structure.
1. Gross neuroanatomy: focus on general structures and connections visible with the eye
2. Microscopic anatomy: describe the organisation of neurons and their connections and
subcellular structure
Methods in neuroanatomy
Different approaches are used to investigate the nervous system at different levels of description.
For identification of gross anatomy, the first challenge is to figure out how to view the brain. The
brain is surrounded by tough dura mater = dense layers of collagenous fibres.
The gyri are the protruding rounded surfaces and the primary sulci are the enfolded regions that
appear as lines and creases.
Slicing through the brain reveals the dichotomy of grey matter and white matter. The grey matter
forms a continuous cortical sheath surrounding a homogeneous mass of white matter. Grey matter
contains cell bodies of neurons and glia and a lot of blood vessels. White matter looks lighter because
of the myelinisation of the axons.
With microanatomy the difference between grey and white matter is determined. A primary concern
for neuroanatomists is to identify the patterns of connectivity in the nervous system in order to lay
out the neural “highways” that allow information to get from one place to another. This is hard
because there is tremendous convergence and divergence in the nervous system.
The human nervous system:
Central nervous system (CNS) = brain + spinal cord (command and control)
Peripheral nervous system = peripheral nerves (courier)
Cerebral cortex
The cerebral cortex has two symmetrical hemispheres that consist of large sheets of layered
neurons. Forebrain = cerebral cortex + basal ganglia + diencephalon. The cortex is about 1.5 to 4.5
mm thick and contains cell bodies of neurons, their dendrites and some axons. The cortex also
includes axons of neurons projecting to the cortex from other brain regions (thalamus). Last, the
cortex contains blood vessels.
The cerebral hemispheres have five main divisions. They are different in function and can be
distinguished from one other by anatomical landmarks (sulci).
1. Frontal lobe: plays a major role in the planning and
execution of movements (motor areas).
2. Parietal lobe
3. Temporal lobe
4. Occipital lobe
5. Limbic lobe
The lateral fissure (sylvian fissure) separates the temporal lobe from
the frontal and parietal lobes.
, The left and right cerebral hemispheres are separated by the interhemispheric fissure (longitudinal
fissure). Interconnections between the cerebral hemispheres are accomplished by axons that travel
through the corpus callosum.
Brodmann classified the brain based on the microanatomy of cell types and their organisation
(cytoarchitecture). He identified 52 regions of the cerebral cortex. Although, a combination of
cytoarchitecture and functional descriptions of the cortex is probably most effective in dividing the
cerebral cortex into meaningful units.
A more functional division is the lobe division. The frontal lobe plays a major role in the planning and
execution of movements. Two main divisions:
1. Motor cortex: includes precentral gyrus (also called the motor strip) represents the
primary motor cortex.
2. Prefrontal cortex: takes part in the higher aspects of motor control and planning and
execution of behaviour.
The parietal lobe contains the somatosensory areas (SI and SII).
The occipital lobe contains the visual cortex (V1).
The temporal lobe contains the auditory cortex (AI and AII).
Higher mental processes are the domain of the association cortical areas (neocortex), in interaction
with sensory and motor areas of cortex (lobes).
Limbic system, basal ganglia, hippocampus, hypothalamus and
diencephalon
The limbic lobe is part of the forebrain that together forms a
border around the brain stem. The limbic system participates
in emotional processing, learning and memory.
The amygdala is a group of neurons anterior to the
hippocampus.
The basal ganglia are a collection of subcortical neuronal
groups in the forebrain, located beneath the anterior portion
of the lateral ventricles. The basal ganglia have a significant
role in the control of movement. Three main subdivisions: globus pallidus, caudate nucleus and
putamen. Caudate and putamen are the input
structures of the basal ganglia. Input comes also from
the thalamus. The major outputs of the basal ganglia
project from the pallidus to thalamic nuclei. Thus, the
basal ganglia are not in a projection pathway from
motor areas to the spinal cord, to control muscular
activity directly, but instead are part of a cortical-
subcortical motor loop that is thought to monitor
aspects of how motor activity is progressing.
The temporal lobe contains the hippocampus and can be divided into zones: CA (CA1, CA2, CA3,
CA4). The hippocampus looks like a sea horse. Input is from the entorhinal cortex. Output goes via
the fornix (a large white matter tract). The hippocampus plays a role in emotional processing and
memory.
Chapter 3. Gross and Functional Anatomy of Cognition (cognitive
neuroscience)
Neuroanatomy = the study of the nervous system’s structure.
1. Gross neuroanatomy: focus on general structures and connections visible with the eye
2. Microscopic anatomy: describe the organisation of neurons and their connections and
subcellular structure
Methods in neuroanatomy
Different approaches are used to investigate the nervous system at different levels of description.
For identification of gross anatomy, the first challenge is to figure out how to view the brain. The
brain is surrounded by tough dura mater = dense layers of collagenous fibres.
The gyri are the protruding rounded surfaces and the primary sulci are the enfolded regions that
appear as lines and creases.
Slicing through the brain reveals the dichotomy of grey matter and white matter. The grey matter
forms a continuous cortical sheath surrounding a homogeneous mass of white matter. Grey matter
contains cell bodies of neurons and glia and a lot of blood vessels. White matter looks lighter because
of the myelinisation of the axons.
With microanatomy the difference between grey and white matter is determined. A primary concern
for neuroanatomists is to identify the patterns of connectivity in the nervous system in order to lay
out the neural “highways” that allow information to get from one place to another. This is hard
because there is tremendous convergence and divergence in the nervous system.
The human nervous system:
Central nervous system (CNS) = brain + spinal cord (command and control)
Peripheral nervous system = peripheral nerves (courier)
Cerebral cortex
The cerebral cortex has two symmetrical hemispheres that consist of large sheets of layered
neurons. Forebrain = cerebral cortex + basal ganglia + diencephalon. The cortex is about 1.5 to 4.5
mm thick and contains cell bodies of neurons, their dendrites and some axons. The cortex also
includes axons of neurons projecting to the cortex from other brain regions (thalamus). Last, the
cortex contains blood vessels.
The cerebral hemispheres have five main divisions. They are different in function and can be
distinguished from one other by anatomical landmarks (sulci).
1. Frontal lobe: plays a major role in the planning and
execution of movements (motor areas).
2. Parietal lobe
3. Temporal lobe
4. Occipital lobe
5. Limbic lobe
The lateral fissure (sylvian fissure) separates the temporal lobe from
the frontal and parietal lobes.
, The left and right cerebral hemispheres are separated by the interhemispheric fissure (longitudinal
fissure). Interconnections between the cerebral hemispheres are accomplished by axons that travel
through the corpus callosum.
Brodmann classified the brain based on the microanatomy of cell types and their organisation
(cytoarchitecture). He identified 52 regions of the cerebral cortex. Although, a combination of
cytoarchitecture and functional descriptions of the cortex is probably most effective in dividing the
cerebral cortex into meaningful units.
A more functional division is the lobe division. The frontal lobe plays a major role in the planning and
execution of movements. Two main divisions:
1. Motor cortex: includes precentral gyrus (also called the motor strip) represents the
primary motor cortex.
2. Prefrontal cortex: takes part in the higher aspects of motor control and planning and
execution of behaviour.
The parietal lobe contains the somatosensory areas (SI and SII).
The occipital lobe contains the visual cortex (V1).
The temporal lobe contains the auditory cortex (AI and AII).
Higher mental processes are the domain of the association cortical areas (neocortex), in interaction
with sensory and motor areas of cortex (lobes).
Limbic system, basal ganglia, hippocampus, hypothalamus and
diencephalon
The limbic lobe is part of the forebrain that together forms a
border around the brain stem. The limbic system participates
in emotional processing, learning and memory.
The amygdala is a group of neurons anterior to the
hippocampus.
The basal ganglia are a collection of subcortical neuronal
groups in the forebrain, located beneath the anterior portion
of the lateral ventricles. The basal ganglia have a significant
role in the control of movement. Three main subdivisions: globus pallidus, caudate nucleus and
putamen. Caudate and putamen are the input
structures of the basal ganglia. Input comes also from
the thalamus. The major outputs of the basal ganglia
project from the pallidus to thalamic nuclei. Thus, the
basal ganglia are not in a projection pathway from
motor areas to the spinal cord, to control muscular
activity directly, but instead are part of a cortical-
subcortical motor loop that is thought to monitor
aspects of how motor activity is progressing.
The temporal lobe contains the hippocampus and can be divided into zones: CA (CA1, CA2, CA3,
CA4). The hippocampus looks like a sea horse. Input is from the entorhinal cortex. Output goes via
the fornix (a large white matter tract). The hippocampus plays a role in emotional processing and
memory.
