Neurolab Practical Connections and Functions

Amygdala

Function: Processes emotion, especially fear/threat, emotional learning, aggression, and emotional memories. Connections: Hippocampus (emotional memories), hypothalamus (autonomic/emotional responses), prefrontal cortex (emotion regulation), thalamus (sensory information), olfactory areas (emotional responses to smell). Spotting: Almond-shaped structure in the medial temporal lobe, anterior to the hippocampus.

Anterior Commissure

Function: Allows communication between the two hemispheres, especially temporal and olfactory regions. Connections: Connects left and right temporal lobes and amygdala/olfactory-related regions. Spotting: Small white-matter bundle crossing the midline anterior to the columns of the fornix.

Caudate

Function: Movement selection, motor planning, habit learning, and procedural learning. Connections: Cortex → caudate → globus pallidus → thalamus → cortex; also interacts with substantia nigra. Spotting: C-shaped gray-matter structure that follows the lateral ventricle.

Cerebellum

Function: Coordinates movement, balance, posture, timing, motor learning, and error correction. Connections: Communicates with the brainstem through the superior, middle, and inferior cerebellar peduncles; receives information from cortex and sensory systems. Spotting: Large wrinkled structure posterior to the pons and medulla; contains tree-like arbor vitae.

Cerebral Aqueduct

Function: Allows CSF to flow from the third to fourth ventricle. Connections: Third ventricle → cerebral aqueduct → fourth ventricle. Spotting: Very narrow channel running through the midbrain.

Choroid Plexus

Function: Produces cerebrospinal fluid (CSF). Connections: Located within the ventricular system and associated with the ventricular blood supply. Spotting: Frilly/vascular-looking tissue inside the ventricles.

Cingulate Cortex (Gyrus)

Function: Emotion, motivation, attention, pain processing, and emotional aspects of memory. Connections: Hippocampus, thalamus, hypothalamus, prefrontal cortex, and amygdala; part of the limbic system. Spotting: Gyrus that curves around the superior surface of the corpus callosum.

Superior Colliculus

Function: Visual orienting and reflexes; helps direct the eyes and head toward visual stimuli. Connections: Retina/visual pathways, visual cortex, and brainstem motor systems. Spotting: Upper pair of bumps on the dorsal midbrain.

Inferior Colliculus

Function: Auditory processing and auditory reflexes. Connections: Receives auditory information from brainstem pathways and projects to the medial geniculate nucleus. Spotting: Lower pair of bumps on the dorsal midbrain.

Corpus Callosum

Function: Allows communication between the left and right cerebral hemispheres. Connections: Connects corresponding cortical regions across hemispheres. Spotting: Large C-shaped white-matter structure in the midline.

Corona Radiata

Function: Carries ascending and descending information between the cerebral cortex and deeper brain structures. Connections: Cortex ↔ internal capsule ↔ thalamus/brainstem/spinal cord. Spotting: Fan-shaped white matter spreading outward from the internal capsule toward the cortex.

Entorhinal Cortex

Function: Major gateway for memory and spatial information entering and leaving the hippocampus. Connections: Neocortex ↔ entorhinal cortex ↔ hippocampus. Spotting: Medial temporal cortex immediately adjacent to the hippocampus.

External Capsule

Function: White-matter pathway for communication between cortical and subcortical regions. Connections: Located lateral to the putamen and medial to the insula; carries fibers between cortical areas and deeper structures. Spotting: White-matter layer immediately lateral to the putamen.

Fornix

Function: Major pathway carrying information from the hippocampus as part of the memory circuit. Connections: Hippocampus → fimbria → fornix → mammillary bodies; also connects with septal and hypothalamic regions. Spotting: C-shaped white-matter tract beneath the corpus callosum.

Frontal Lobe

Function: Executive functions, planning, decision-making, personality, voluntary motor control, working memory, and speech production. Connections: Extensive connections with parietal, temporal, and limbic regions, thalamus, and basal ganglia. Spotting: Most anterior cerebral lobe; primary motor cortex is in the precentral gyrus.

Globus Pallidus

Function: Regulates movement by providing inhibitory output from the basal ganglia. Connections: Striatum → globus pallidus → thalamus → motor cortex; interacts with substantia nigra and subthalamic nucleus. Spotting: Medial to the putamen.

Hippocampus

Function: Formation of new memories, learning, and spatial memory. Connections: Entorhinal cortex → hippocampus → fimbria → fornix → mammillary bodies; also interacts with amygdala, cingulate cortex, and thalamus. Spotting: Curved structure deep in the medial temporal lobe.

Fimbria

Function: Collects hippocampal output fibers and carries them toward the fornix. Connections: Hippocampus → fimbria → fornix → mammillary bodies/septal regions. Spotting: White-matter fibers along the medial edge of the hippocampus.

Hypothalamus

Function: Homeostasis, temperature regulation, hunger, thirst, hormones, autonomic function, sleep/wake cycles, reproduction, and stress responses. Connections: Thalamus, pituitary gland, hippocampus, amygdala, brainstem, and spinal cord. Spotting: Located directly inferior to the thalamus.

Insula

Function: Interoception, taste, pain processing, emotional awareness, and autonomic responses. Connections: Limbic system, frontal cortex, thalamus, and brainstem. Spotting: Hidden cortex buried deep within the lateral sulcus.

Internal Capsule

Function: Major pathway carrying motor and sensory information between the cerebral cortex and deeper structures. Connections: Cortex ↔ thalamus/brainstem/spinal cord; contains corticospinal, corticobulbar, and thalamocortical fibers. Spotting: Deep white matter between the basal ganglia and thalamus.

Mammillary Bodies

Function: Memory processing and part of the Papez circuit. Connections: Hippocampus → fornix → mammillary bodies → anterior thalamus → cingulate cortex → hippocampus. Spotting: Small paired rounded structures on the inferior surface of the hypothalamus.

Medulla

Function: Controls vital autonomic functions including breathing, heart rate, blood pressure, swallowing, coughing, and vomiting. Connections: Continuous with the pons superiorly and spinal cord inferiorly; communicates with cerebellum and higher brain regions. Spotting: Lowest part of the brainstem immediately above the spinal cord.

Occipital Lobe

Function: Visual processing. Connections: Retina → optic pathways → thalamus → occipital cortex; also connects with temporal and parietal association areas. Spotting: Posterior-most cerebral lobe.

Olfactory Bulb

Function: Initial processing of information about smell. Connections: Olfactory receptors → olfactory nerve → olfactory bulb → olfactory tract → olfactory/limbic regions. Spotting: Small structure on the inferior/anterior surface of the frontal lobe.

Optic Chiasm

Function: Allows visual information from both eyes to cross and reach the appropriate hemisphere. Connections: Optic nerves → optic chiasm → optic tracts → lateral geniculate nucleus → visual cortex. Spotting: X-shaped crossing at the base of the brain; nasal retinal fibers cross here.

Parietal Lobe

Function: Somatosensation, spatial awareness, attention, body representation, and sensory integration. Connections: Frontal, temporal, and occipital lobes plus thalamus. Spotting: Cerebral lobe behind the frontal lobe and above the temporal lobe; primary somatosensory cortex is in the postcentral gyrus.

Pineal Gland

Function: Produces melatonin and helps regulate circadian rhythms and sleep/wake cycles. Connections: Retina → suprachiasmatic nucleus/hypothalamus → sympathetic pathway → pineal gland. Spotting: Small gland near the posterior third ventricle.

Pons

Function: Relays information between the cerebrum and cerebellum and participates in breathing and cranial nerve functions. Connections: Strongly connected with the cerebellum through the middle cerebellar peduncle; part of major ascending and descending brainstem pathways. Spotting: Large rounded bulge in the middle of the brainstem.

Posterior Commissure

Function: Helps coordinate certain visual reflexes, especially pupillary responses and vertical eye movements. Connections: Crosses near the posterior third ventricle and connects regions involved in visual reflexes and eye movement. Spotting: Small crossing fiber tract near the posterior third ventricle in the dorsal midbrain.

Putamen

Function: Movement selection, voluntary movement, motor learning, and habit formation. Connections: Cortex → putamen → globus pallidus → thalamus → cortex; also interacts with substantia nigra. Spotting: Lateral component of the lentiform nucleus; lateral to the globus pallidus.

Septum Pellucidum

Function: Thin membranous partition separating the two lateral ventricles; associated with limbic/septal circuitry. Connections: Located between the lateral ventricles and near the fornix/septal region. Spotting: Thin membrane between the two lateral ventricles.

Substantia Nigra

Function: Dopamine-based modulation of movement; important for basal ganglia function. Connections: Substantia nigra pars compacta → dopamine → caudate/putamen; interacts with basal ganglia circuits. Spotting: Dark band in the midbrain; substantia nigra means "black substance."

Spinal Cord

Function: Carries sensory and motor information between the brain and body and produces reflexes and contributes to autonomic functions. Connections: Continuous with the medulla and connects with peripheral nerves through spinal roots. Spotting: Long neural structure extending inferiorly from the medulla.

Temporal Lobe

Function: Hearing, language comprehension, memory, emotion, and object/face recognition. Connections: Hippocampus, amygdala, frontal cortex, occipital cortex, and thalamus. Spotting: Lateral cerebral lobe inferior to the lateral sulcus.

Thalamus

Function: Major relay center for sensory, motor, attention, arousal, consciousness, and limbic information. Connections: Sensory systems → thalamus → cerebral cortex; basal ganglia → thalamus → motor cortex; limbic structures → thalamus → cingulate/cortex. Spotting: Large oval structure near the center of the brain, superior to the hypothalamus.

Lateral Ventricles

Function: CSF-filled spaces within the cerebral hemispheres. Connections: Lateral ventricles → interventricular foramina → third ventricle. Spotting: Large C-shaped spaces, one in each cerebral hemisphere.

Third Ventricle

Function: CSF-filled cavity in the midline of the diencephalon. Connections: Lateral ventricles → third ventricle → cerebral aqueduct. Spotting: Narrow midline space between the thalami.

Fourth Ventricle

Function: CSF-filled cavity between the brainstem and cerebellum. Connections: Third ventricle → cerebral aqueduct → fourth ventricle → subarachnoid space/central canal. Spotting: Space between the pons/medulla anteriorly and cerebellum posteriorly.