Exam 1 - Neuroscience

Amygdala

Fear and anger.. the emotions guys feel if u hit their almond shaped clusters

Peripheral Nervous System

Has two components: •Somatic- voluntary control over our skeletal muscles •Autonomic- controls the glands and muscles of internal organs. Usually operates on its own (autonomous). •Autonomic System also has two components: - Parasympathetic- Slows down body. Decreases heart beat, lowers blood sugar, etc. - Sympathetic- Arouses your body. Accelerates heart beat, raises blood pressure, etc.

The Nervous System

Nervous System- an interacting network of neurons that conveys electrochemical information throughout the body. •Central Nervous System (CNS)- the brain and spinal cord. •Peripheral Nervous System (PNS)- the sensory and motor neurons that connect the CNS to the rest of the body's senses, muscles, and glands.

Major Types of Neurons

Sensory Neurons - receive information from the external world and convey this information to the brain via the spinal cord. Motor Neurons - carry signals from the spinal cord to the muscles to produce movement. Interneurons - connect sensory neurons, motor neurons, or other interneurons.

The Midbrain

first thing that orients people in books while waking up is sound of a clock "tec-tum-tec-tum-tec-tum..." "tug-mentum" involved in pleasure seeking and arousal

The Hippocampus

kinda looks like a thin crescent moon... "memories!all alone in the moonlight!..."

The Hindbrain

pons - in Family Guy Peter relayed important info about the "Fonz" to the rest of his church Reticular formation- ... for some people the rectum plays an important role in arousal

The Forebrain

• Cerebral Cortex - Outermost layer of the brain, divided in to two hemispheres. • Subcortical Structures - areas of the forebrain, housed under the cerebral cortex near the very center of the brain. -Thalamus -Pituitary gland -Basal Ganglia -Limbic system

Chemical Signaling

•Axons usually end in terminal buttons - knoblike structures that branch out from an axon. •Terminal buttons are filled with tiny "bags" that contain neurotransmitters. •When an action potential reaches the end of the axon, it triggers the release of neurotransmitters. -Neurotransmitter- chemical messengers that are sent in to the synapse and bind to the receiving neuron. •The dendrites of a receiving neuron contain receptors that receive neurotransmitters and initiate a new action potential.

Central Nervous System

•Comprised of Brain & Spinal Cord •Spinal Cord Conduit between peripheral nervous system and the brain Organizes certain behaviors without the brain. Governs our reflexes. •Reflexes- a simple, automatic response to a sensory stimulus.

Altering Neurotransmission

•Drugs and chemicals can alter our neurotransmission. •When flooded with drugs that produce certain effects (e.g., euphoria), our brain will stop making similar neurotransmitters on its own. •Various drugs excite or inhibit our neurons' firing. Agonists- drugs that increase the action of a neurotransmitter. Antagonists- drugs that block the function of a neurotransmitter.

Parts of the Neuron

•Each neuron consists of a cell body and its branching fibers (dendrites). •Dendrites- the branching extensions of a neuron that receive information from other neurons and relay it to the cell body. •Information is passed from the dendrites along the axon. •Axon- the extension of a neuron that transmits information to other neurons, muscles, or glands. •Axons can be very long and are covered in a myelin sheath. •Myelin - insulating layer of fatty tissue on an axon to help speed the impulses. Composed of glial cells.

Neural Impulses

•Neural impulses can travel from 2 to 200 mph. •A neuron "fires" an 'action potential' when it receives a signal from your sensory receptors (pressure, light, heat, etc.) or chemicals from other neurons. -Action Potential - a neural impulse; a brief electrical charge that travels down the length of the axon to the synapse. -Generated by the movement of positively charged atoms in and outside of the axon's membrane •After the A.P. fires the membrane channels return to their original state. -K+ flows out until axon reaches resting potential - difference in electric charge between the inside and outside of a neuron's cell membrane. • When ions are imbalanced the neuron is in refractory period - time following action potential when new A.P. cannot be initiated.

Neurons

•Our "information system" is made up from billions of neurons. -Neuron- cells in the nervous system that communicate with one another to perform information-processing tasks. •There are many different types of neurons, but all are built rather similarly.

Splitting the Brain

•Our two hemispheres often work together. •However, the left hemisphere generally processes reading, writing, speaking, mathematics, and comprehension skills. •Occasionally, patients require a "split-brain" procedure.