Organization of the Brain

Plasticity of the Brain

• The brain has an amazing ability to change and adapt to facilitate our needs.

1. Like muscles the brain can develop itself where it need to. (The example of the somatosensory cortex being enlarged when someone is a musician and they need great dexterity in their fingers.)

2. The brain can reorganize pathways. If damage is done to nerve tissues and it isn’t receiving information the brain will divert the neurons to work on some other part. (This includes damage to the brain itself)

3. The brain can generate new neurons.

Disclaimer

• Plasticity is limited

• With severe brain damage there are limits to how much the brain can rewire

• Unfortunately as you grow older there are limits to how many new cells are generated

Endocrine System

Endocrine System

• The endocrine system is made up of numerous glands that are located throughout the body. These glands secrete various chemicals, called hormones, which affect organs, muscles and other glands in the body.

• Even though hormones are very similar to neurotransmitters, there are some basic differences

• Neurotransmitters messages are transmitted short distances with lightning speed

• Hormones are transmitted over a greater distance at a much slower rate.

• Unlike the target specific neurotransmitter the hormone often targets many cells, and organs

Hypothalamus

• Is often called the control center of the endocrine system

• The hypothalamus controls the pituitary gland

Pituitary Gland

• Sometimes known as the master gland

• Is located directly below the hypothalamus

• Is divided into 2 parts

1. Posterior: Regulates water and salt balance

(A dysfunction in the gland can cause a less common form of diabetes)

• Anterior Pituitary: Regulates growth, also produces hormones that control the adrenal cortex, pancreas, thyroid and gonads

(Dysfunction: Too little growth hormone produces dwarfism; too much causes gigantism)

Pancreas• This organ regulates the level of sugar in

the bloodstream by secreting the hormone insulin

• The under or over production of insulin can cause the more common form of diabetes

Thyroid

• Is located in the neck• The Largest of the glands• Regulates metabolism• It produces the hormone Thyroxin.• (Dysfunction: Hormone deficiency during

development leads to stunted growth and mental retardation. Under secretion during adulthood leads to reduction of motivation. Over secretion results in high metabolism, weight loss and nervousness)

Adrenal Glands

• Adrenal Cortex (Outside) regulate sugar and salt balances and help body reduce stress, they are responsible for the growth of pubic hair (secondary sex characteristic)

• The Adrenal Medulla (inside part) they produce 2 hormones that arouse the body and help us deal with stress– Epinephrine (adrenaline)– Norepinephrine (noradrenaline)

Gonads

• In females, the ovaries produce hormones that regulate sexual development, ovulation, and growth of sex organs

• In males, the testes produce hormones that regulate sexual development, production of sperm, and growth of sex organs

• Dysfunction: lack of sex hormone during puberty results in lack of secondary sexual characteristics (facial and body hair, muscles in males, breasts in females)

Hemispheric Specialization

Left• Language, reading,

writing, spelling• Mathematical• Analytic• Recognizing Self

(Memories, understanding of oneself)

Right• Although mute, the right has a

childlike ability to read, write and understand speech

• Spatial

• Holistic: The right combines parts into a meaningful whole

• Recognizing others

The End