Hippocampus
The hippocampus is responsible for the formation of
short-term and long-term memory. In
addition, it plays an important role in
spatiotemporal
orientation. The hippocampus is
bordered ventrally by the thalamus and dorsally
by the
corpus callosum. While the
hippocampus is completely covered by the
cerebrocortical
mantle, it is separated from the
cortex by white matter.
Olfactory Bulb
The mouse olfactory bulb is a designated region to
receive,
integrate and transmit olfactory
information. Olfaction is behaviorally the most
important sense for mice and this is
reflected in the comparatively large (compatred
to e.g.
primates), prominent structure at
the cranial end of the mouse brain. The
olfactory bulb
borders caudally with the cerebral
cortex and is the only main sensory complex
which
transduces information directly to the
cerebrum, bypassing the thalamus. Olfactory
input is
critical for numerous actions, e.g.
identification of other mice and mediation of
emotional
responses, reproductive and maternal
behavior, detection of predators and food
selection.
Rest Brain
The rest brain comprises several distinct anatomical
regions, namely the nucleus accumbens, the
ventral striatum, the caudate putamen and the
basal forebrain. It is located ventral of the
cerebral cortex and forms the base of the mouse
brain, bordering rostral to the olfactory bulb
and caudal to the thalamus respectively
hypothalamus. Functionally, it integrates the
input of telencephalic and non-telencephalic
regions of the brain and plays a role in a
multitude of processes such as motor control,
sensorimotor behavior and habit formation. In
humans, this region and its afferent structures
are also associated with a number of distinct
neurodegenerative diseases, such Parkinson’s and
Huntington’s disease. Furthermore, specifically
the nucleus accumbens is part of the
dopaminergic reward system and involved in many
addictive behavioral disorders.
Hypothalamus
The hypothalamus controls important high-level
physiological
processes such as blood
pressure, body temperature, breathing, circadian
rhythm,
food intake and digestion and
reproduction. It regulates the endocrine and
cardiovascular system, releasing several
neuroendocrine hormones and is also closely
associated
with glands like the pituitary and
thyroid gland. The Hypothalamus is located at
the bottom
surface of the brain lying on the
skull base, ventral of the thalamus.
Thalamus
The thalamus mediates almost all sensory and motor
signals
and relays them to the cerebral
cortex. Information input occurs from the
brainstem,
spinal cord, cerebellum, amygdala and
the caudate putamen. A key exception is the
olfactory
sense, which bypasses the thalamus. It
is a structure of gray matter located deep
inside the
brain dorsal of the hypothalamus,
bordering the Cerebrum cranially and the
midbrain
caudally.
Hypophysis
The
Hypophysis (also known as pituitary gland) is a
small sized endocrine gland located in a bony
cavity called the sella
turcica, part of the sphenoid
bone of the mouse skull directly beneath the
hypothalamus, to which it is connected by a
slender stalk called the infundibulum.
It is composed of two lobes of different
embryonic origin and function, the anterior lobe
or adenohypophysis and the posterior lobe or
neurohypophysis. The anterior pituitary contains
various hormone-secreting cells responsible for
producing and releasing
several key hormones (e.g. growth hormone (GH),
thyroid-stimulating hormone (TSH),
follicle-stimulating hormone (FSH) and
luteinizing hormone (LH)). The posterior
pituitary does not produce hormones itself but
stores and releases hormones like oxytocin and
vasopressin (antidiuretic hormone, ADH) that are
synthesized in the hypothalamus.
The mouse pituitary gland, often referred to as
the "master gland" of the endocrine system, is
itself regulated by neurosecretory neurons
located in the hypothalamus
(hypothalamic-pituitary axis) and a feedback
mechanism from circulating hormonal signaling
originating
from various target tissues. As a central hub in
the endocrine system, the pituitary gland plays
a crucial role in regulating growth, metabolism,
stress responses, reproduction, and fluid
balance. Disruptions in its function—whether due
to altered hormonal
pathways or tumor growth—can lead to a range of
diseases, including hypopituitarism, acromegaly,
Cushing’s disease, and diabetes insipidus.
Midbrain
The midbrain is the most cranial part of the mouse
brainstem.
It continues caudally with the
pons and borders cranially with thalamus,
hypothalamus
and parts of cerebrocortical mantle.
The midbrain houses importand dopaminergic
neuron
populations in its ventral region which
play a significant role in motor control.
Furthermore,
the midbrain controls extra- and
intraocular eye muscles via the oculomotor and
trochlear
nerves.
Cerebellum
The cerebellum is an important structure for the
control and
learning of motor actions but
plays also a port in regulating arousal, emotion
and
cognition. The cerebellum is the most
dorsal part of the brainstem, composed of white
and gray
matter and located at the
dorsocaudal end of the brain. Unlike the smooth
cerebrum, the cerebellum can be easily
identified by the transverse sulci on its
surface.
Pons
The Pons is a direct continuation of the medulla and
borders
dorsally with the cerebellum and
rostrally with the midbrain. It houses several
nuclei of
important nerves involved in e.g.
the sense of equilibrium, hearing and the
control of the
jaw and fascial muscles.
Furthermore, it is the anatomical connection of
the
cerebullum with the spinal cord and the
rest of the mouse brain.
Medulla
The Medulla is located at the caudal end of the mouse
brain
and forms ist connection with the
spinal cord. In contrast to the spinal cord, it
is
endowed with nuclei of nerves for the
innervation of various craniofascial structures
such as
the tongue, the muscles of the
pharynx and larynx and additionally some neck
muscles.
Choroid Plexus
The choroid plexus is a cluster of branching
epithelial
networks covering a capillary
scaffold located in each of the four brain
ventricles.
It houses a specialized, non-neuronal
cell population whose function is to synthesize
and
secrete the cerebrospinal fluid.
Structurally, it functions also as a blood-brain
barrier
and is involved in the removal of
toxins and metabolic waste products from the
central
nervous system. Furthermore, it has a
role in regulating neurogenesis and
inflammation.
Cerebral Cortex
The cortex is the hierarchically highest part of the
central
nervous system in terms of
information processing. It receives and
integrates all
sensory information and is
responsible for voluntary action. The cerebral
cortex is
a large, mantle-like structure
consisting of gray matter and covering deeply
located
parts of the brain like hippocampus,
thalamus, hypothalamus and lateral parts of the
midbrain. Unlike in larger mammals, e.g.
primates, the mouse cortex is smooth and does
not
display sulci or gyri. On the surface, it
borders the olfactory bulb rostrally and the
cerebellum
caudally. Functionally, the cerebral
cortex is organized in a topic fashion, i.e.
defined
cortical regions represent certain
regions of the body.