Controls balance for walking and standing and other functions and processes in both brain and body

Holds more than half of the neurons in your entire body

Those with damage have problems keeping their balance while walking or standing. As well as difficulty reaching for objects to pick up. It can make it difficult to learn new words or skills, affect sense of timing, judging size or distance from objects

Plays a role in regulating emotions and how you make decisions. As it does for movement, the cerebellum provides accuracy, consistency, and appropriateness to cognitive and affective functions

https://my.clevelandclinic.org/health/body/23418-cerebellum

Function of the Pituitary Gland

The pituitary gland is referred to as the “master gland” because it monitors and regulates many bodily functions through the hormones that it produces, including:

• Growth and sexual/reproductive development and function

• Glands (thyroid gland, adrenal glands, and gonads)

• Organs (kidneys, uterus, and breasts)
  (Barrow Neurological Institute)

The pituitary is controlled in large part by the hypothalamus just above the pituitary. By detecting levels of hormones produced by glands under pituitary's control (target glands), the hypothalamus or the pituitary can determine how much stimulation the target glands need.

The pituitary has two distinct parts:

• Front (anterior) lobe, which accounts for 80% of the pituitary gland's weight

• Back (posterior) lobe

The lobes are connected to hypothalamus by a stalk that contains blood vessels and nerve cell projections (nerve fibers, or axons). The hypothalamus controls the anterior lobe by releasing hormones through the connecting blood vessels. It controls posterior lobe through nerve impulses.

Hormones produced by PG are not all produced continuously. Most are released in bursts every 1 to 3 hours, with alternating periods of activity/inactivity. Some of the hormones, such as adrenocorticotropic hormone (ACTH), growth hormone, and prolactin, follow a circadian rhythm: Levels rise and fall predictably during the day, usually peaking just before awakening and dropping to lowest levels just before sleep.

(Merck)

HORMONES

Anterior lobe

• Growth hormone

• Prolactin (to stimulate milk production in the female breast)

• ACTH (adrenocorticotropic hormone which regulates the adrenal glands )

• TSH (thyroid-stimulating hormone which regulates the thyroid gland )

• FSH (follicle-stimulating hormone which regulates the ovaries and testes)

• LH (luteinizing hormone which regulates the ovaries or testes)

Posterior lobe

• ADH (antidiuretic hormone is actually produced in the hypothalamus and stored in the pituitary gland; it increases absorption of water by the kidneys. Also increases blood pressure)

• Oxytocin (to contract uterus during childbirth and stimulate release of milk during breastfeeding)

(Johns Hopkins)

Pituitary Damage/Disorders

Most pituitary tumors are noncancerous (benign). But when a tumor grows on or near the pituitary gland, the tumor can:

• Change hormone production, leading to symptoms such as weight gain, stunted or excessive growth, high blood pressure, low sex drive or mood changes.

• Press against pituitary gland, optic nerves or brain tissue, causing vision problems or headaches.

Rare Disorders

• About six to 11 people in 100,000 live with acromegaly, a disorder caused by too much growth hormone.

• About 10 to 15 people per million are diagnosed with Cushing disease/syndrome, caused by too much cortisol, each year in the U.S.

• Craniopharyngiomas, noncancerous pituitary tumors, affect one or two people per million each year in the U.S.

The basal ganglia are a group of structures deep in the brain near the base of the cerebral hemispheres that help control movement, decision-making, emotions, and motivation. They filter signals from the brain, allowing only necessary movements while blocking unwanted ones. They also play a role in learning, habits, and addiction.

1. Striatum (caudate nucleus & putamen)

2. Globus pallidus (internal & external segments)

3. Subthalamic nucleus

4. Substantia nigra

Functions

1. Movement Control – Helps approve or reject movement signals, ensuring smooth and controlled motions.

2. Decision-Making & Motivation – Processes goals, risks, emotions, and learning. The basal ganglia are involved in emotion regulation, mainly through their connections with brain areas that process mood and reward, such as the prefrontal cortex and limbic system. They help control the initiation of behaviors linked to motivation, reward-seeking, and emotional responses.

3. Reward & Addiction – Influences how we respond to rewards, reinforcing habits and behaviors.

Anatomy

Includes structures like the caudate nucleus, globus pallidus, putamen, and substantia nigra. These structures communicate through excitatory (activating) and inhibitory (blocking) signals. The basal ganglia are about the size of a gumball and comprise neurons (signal transmitters) and glial cells (support cells).

The basal ganglia rely on neurotransmitters like dopamine (for movement initiation and control), GABA (for inhibiting movement), glutamate (for exciting the system), and acetylcholine (for fine-tuning movement). These chemicals balance each other to regulate motor control, and any disruptions in this balance can lead to movement disorders, such as Parkinson’s disease.

Two key neuronal circuits influence the basal ganglia:

1. Nigrostriatal Pathway – Connects the substantia nigra pars compacta to the striatum and uses dopamine to:

   • Excite the direct pathway (promotes movement).

   • Inhibit the indirect pathway (reduces movement suppression).

   • Functions in a reciprocal manner.

   • Related to reward, behavior, and motor learning.

   • Important for voluntary movement and postural balance.

2. Thalamostriatal Pathway – Mostly connects the thalamus to the striatum, with smaller links to the globus pallidus and subthalamic nucleus.

   • Involved in goal-directed behavior.

   • Helps reduce interference between new and existing learning.

Disorders & Symptoms

Conditions affecting the basal ganglia include:

• Parkinson’s Disease – A progressive neurodegenerative disorder caused by the loss of dopamine-producing neurons and the formation of Lewy bodies. Symptoms include tremors, slow movement, stiffness, poor coordination, postural instability, and a shuffling gait.

• Huntington’s Disease – An inherited disorder affecting movement, cognition, and behavior due to degeneration in the striatum and cortex. Symptoms typically appear between ages 30-50 and include involuntary movements (chorea), difficulty walking, speaking, and swallowing, along with cognitive decline, depression, and impulsivity.

• Hemiballismus – A rare disorder causing violent, involuntary limb movements on one side of the body, often due to a lesion in the basal ganglia or subthalamic nucleus. Prognosis is generally good.

• Tourette Syndrome – A neurodevelopmental condition characterized by motor and vocal tics, likely caused by dysfunction in the cortico-basal ganglia network. It can impact quality of life, but treatment options are improving.

• OCD: It's linked to overactivity in certain brain areas, including the orbitofrontal cortex and caudate nucleus. Brain imaging shows abnormal connectivity in these areas, and treatments like deep brain stimulation (DBS) help reduce symptoms by targeting specific regions.

• Addiction: This disorder involves compulsive substance-seeking behaviors. Changes in the basal ganglia, particularly in the striatum, are observed in substance users, leading to theories about reward pathways and impulsivity. Studies suggest altered dopamine receptor activity plays a role in addiction.

• Depression and Anxiety: These disorders involve changes in the ventral striatum, affecting motivation and reward systems. Brain imaging shows altered dopamine and serotonin signaling, and DBS treatments are being explored to reduce symptoms.

• Schizophrenia: Involves issues with decision-making, perception, and memory. Changes in the basal ganglia and other brain regions contribute to these symptoms, and understanding these changes is key to developing effective treatments.

• Injuries & toxins – Strokes, traumatic brain injuries, heavy metal poisoning.

Common symptoms include tremors, muscle weakness, balance issues, speech difficulties, and vision problems.

Diagnosis & Treatment

Tests include MRIs, CT scans, blood tests, and genetic testing. Treatment depends on the condition but may involve medication, surgery, or symptom management.

Prevention

• Eat a balanced diet.

• Stay active and maintain a healthy weight.

• Wear safety gear to prevent head injuries.

• Manage chronic conditions to reduce brain-related risks

How does it work?

Sensory impulses (“information”) travel through nerve fibers from your body through brain structures to your thalamus.

What happens if my thalamus is damaged?

Your thalamus is a central relay station for receiving incoming sensory and motor information. Symptoms of damage to your thalamus include: Memory loss (amnesia).

• Lack of interest or enthusiasm (apathy).

• Loss of ability to understand language or speak (aphasia).

• Trouble with attention, loss of alertness.

• Damage to your thalamus can result in:

  • Unconsciousness and even coma.

  • Sleep disorders, such as insomnia and fatal familial insomnia (inability to sleep, leading to death).

  • Movement disorders, including tremors.

Certain conditions that are affected by or damage your thalamus include:

• Fatal familial insomnia

• Creutzfeldt-Jacob disease

• Korsakoff syndrome.

It’s the main link between your endocrine system and your nervous system.

Your hypothalamus receives chemical messages from nerve cells in your brain and from nerve cells in your body (your peripheral nervous system), which also respond to signals outside your body.

Your hypothalamus’s main function is to react to these messages to keep your body in a stable state or internal balance.

Your hypothalamus helps manage your:

• Body temperature

• Blood pressure

• Hunger and thirst

• Sense of fullness when eating

• Mood

• Sex drive

• Sleep

https://my.clevelandclinic.org/health/body/22566-hypothalamus

Improve amygdala functioning with meditation and exercise

Dysfunction of amygdala connected to PTSD, OCD, and ASD

Damage to amygdala results in poor emotion regulation (primarily with fear responses)

Part of the endocrine system, it is a tiny gland located beneath the back part of the corpus callosum and secretes the hormone melatonin. It is stimulated by darkness and light.

• Light-sensitive nerve cells in the retina detect light and send a signal to the pineal gland. 

• Darkness stimulates melatonin production

• Sleep quality affects functionality

• Light exposure inhibits the production of melatonin and blue light can suppress melatonin production for up to four hours. 

• Reducing fluoride intake, filtering water, and eating fresh, organic foods may help reduce calcifications on the pineal gland. 

• The pineal gland is linked to depression, mania, and seasonal affective disorder

• May help to synchronize circadian rhythm in different parts of your body.

• Damage typically occurs due to a traumatic brain injury (30%-50% of the time).

• Symptoms of Pineal Gland Issues: seizures, memory, headaches, vision changes, and nausea/vomiting.

Your hypothalamus:

• Makes some hormones that are stored elsewhere (in your posterior pituitary)

• Sends signals (hormones) to your pituitary gland, which either releases hormones that directly affect a part of your body or sends another signal (hormone) to a different gland in your body that then releases its hormone

Your pituitary gland sits just below your hypothalamus. It consists of two lobes, called the anterior pituitary and posterior pituitary. Your hypothalamus is connected to and communicates with your anterior lobe through a network of blood vessels. It communicates with your posterior lobe by tissue called the pituitary stalk.

Your hypothalamus sends signals in the form of releasing hormones to tell the anterior and posterior pituitary when to release (secrete) its hormones.

- 2/3 total weight of the brain

- Outer surface called cerebral cortex: mostly smooth, has wrinkles - picture a walnut. Ridges (gyri) and folds (sulci) make these wrinkles.

- Two hemispheres: left and right, connected by the corpus callosum

- Each hemisphere has five main lobes each: frontal (front), parietal (top), temporal (sides), insular (deep inside), occipital (back/bottom)

- Handles conscious thoughts: five senses (manages and processes all we take in), language (ability to read, speak, write), working memory (short-term), behavior and personality (acts as a filter to stop you from doing/saying things you'll later regret), and learning, logic, and reasoning skills.

- Example of working together with other parts of the brain (cerebellum): picking up a pencil off a table. Your cerebrum sends the signals to the muscles in your arms, and your cerebellum helps calculate and control your movements, so your hand goes right to the pencil without missing.

- TBI: Symptoms 

• Personality disorders

• Difficulty learning and thinking

• Loss of senses

• Limb weakness

• Balance and coordination issues

• Muscle rigidity or spasticity

• Abnormal movements, such as tremor or chorea