Psychology 2nd Chapter

For Test 1

Phrenology

In the 1800s, Franz Gall suggested that bumps of the skull represented mental abilities.

Nervous system

Caries information to and from all parts of the body.

Central nervous system

The brain and spinal cord

Brain

Interprets and stores information and sends orders to muscles, glands, and organs.

Spinal cord

Pathway connecting the brain and the peripheral nervous system.

Peripheral nervous system

Transmits information to and from the central nervous system.

Autonomic nervous system

Automatically regulates glands, internal organs and blood vessels, pupil dilation, digestion, and blood pressure.

Parasympathetic division

Maintains body functions under ordinary conditions; saves energy.

Sympathetic division

Prepares the body to react and expend energy in times of stress.

Somatic nervous system

Carries sensory information and controls movement of the skeletal muscles.

Sensory system (afferent)

Carries messages from senses to CNS.

Motor system (efferent)

Carries messages from CNS to muscles and glands.

Autonomic NS: Sympathetic Division (i.e. fight or flight)

• Dilates pupils and inhibits tear glands

• Decreases salivation

• Dilates bronchi (widening air passages that carry air into and out of lungs)

• Decreases digestive functions of stomach, pancreas, and intestines

• Inhibits bladder contraction

Autonomic NS: Parasympathetic Division (i.e. rest and digest)

• Constricts pupils and stimulates tear glands

• Increases salivation

• Slows heart rate

• Constricts bronchi

• Increases digestive functions of stomach, pancreas, and intestines

• Allows bladder contraction

The brain is made up of two type of cells:

Neurons and Glial Cells

Neurons

Receive and send chemical messages

Glial cells

Separate, support, and insulate the neurons

Functions of neurons

Neurons are the elementary components of the nervous system-the body’s speedy electrochemical system.

Neuron receives signals through branching dendrites and sends signals through its axons.

Some axons are encased in the myelin sheath, which enables faster transmission.

Functions of glial cells

They provide myelin and support, nourish, and protect neurons.

They may also play a role in learning, thinking, and memory.

What happens if a combined signal received by a neuron exceeds a minimum threshold?

The neuron fires, transmitting an electrical impulse down its axon through a chemistry-to-electricity process.

The neuron’s reaction is…

an all-or-none response.

Action potential

A neural impulse.

A brief electrical charge that travels down an axon - positively charged atoms in and out.

Neural impulse

All or none - like the firing of a musket, the neuron either fires completely or it does not fire at all.

The graph of a neural impulse contains 4 positions, what are they?

1) Resting potential

2) Action potential

3) Hyperpolarization

4) Resting potential

Repeat

Action potential properties

Intensity of an action potential remains the same throughout the length of the axon.

Do you know the structure of a neuron?

Yes or no (reflect and memorize)

Do you know the structure of the Synapse?

Yes or no (reflect and memorize)

Neural communication

Neurotransmitters in the synapse are reabsorbed into the sending neurons.

Neurotransmitter

A chemical messenger that carries signals from one nerve cell to the next target cell across a tiny gap called a synapse.

Serotonin (basic function)

Involved in mood, sleep, and appetite.

Serotonin (detailed function)

Affects mood, hunger, sleep, and arousal.

Undersupply linked to depression. Some drugs that raise serotonin levels are used to treat depression.

Dopamine (basic function)

Involved in control of movement and sensations of pleasure.

Dopamine (detailed function)

Influences movement, learning, attention, and emotion.

Oversupply linked to schizophrenia. Undersupply linked to tremors and decreased mobility in Parkinson’s disease.

Acetylcholine (ACh) (basic function)

Involved in arousal, attention, memory, and controls muscle contractions.

Acetylcholine (ACh) (detailed function)

Enables muscle action, learning, and memory

With Alzheimer’s disease, ACh-producing neurons deteriorate.

Endorphins (basic function)

Involved in pain relief.

Endorphins (detailed function)

Neurotransmitters that influence the perception of pain or pleasure.

Oversupply with opiate drugs (like morphine which manages pain post surgery) can suppress the body’s natural endorphin supply.

Norepinephrine (basic function)

Involved in arousal and mood.

Norepinephrine (detailed function)

Helps control alertness and arousal.

Undersupply can depress mood.

GABA (gamma-aminobutyric acid) (basic function)

Involved in sleep and inhibits movement.

GABA (gamma-aminobutyric acid) (detailed function)

A major inhibitory (decreases the likelihood that a receiving neuron will fire an electrical signal) neurotransmitter.

Undersupply linked to seizures, tremors, and insomnia.

Glutamate (basic function)

Involved in learning, memory formation, nervous system development, and synaptic plasticity.

Glutamate (detailed function)

A major excitatory (increases the chance that a receiving nerve cell will fire an electrical signal called an action potential) neurotransmitter; involved in memory.

Oversupply can overstimulate the brain, producing migraines or seizures (which is why some people avoid MSG, monosodium glutamate, in food).

Agonist molecules

Increase neurotransmitter action.

Antagonist molecules

Decrease neurotransmitter action.

Remember to check out the Synapse diagram regarding dopamine.

Okay thanks for the reminder!

A person with a damaged brain: Phineas Gage. What happened to him? What were the conclusions about the brain?

A 3.5 foot iron rod went through his left frontal lobe and he ended up surviving. It led to a shift in his personality and behavior. It was evidential to the fact that the brain has specific regions for different functions.

The Brainstem and Thalamus (review diagrams about all of these brain parts)

The brainstem is an extension of the spinal cord. The thalamus is attached to the top. The reticular formation passes through both structures.

The Hindbrain

Lower back of the skull, right above and connected to the spinal cord.

Pons

Involved in sleep and left-right body coordination.

Cerebellum

Controls balance and movements like posture and walking.

Medulla

Life-sustaining functions like breathing, swallowing, and heart rate.

Reticular Formation

General attention, alertness, and arousal.

The Limbic System

A group of several brain structures located under the cortex.

Regulates emotions and drives . . .?

Amygdala

Two bean-sized neural clusters; emotions.

Hypothalamus

Neural system below the thalamus; directs maintenance activities; helps guide the endocrine system via the pituitary gland; emotion and reward

Hippocampus

Seahorse-shaped neural structure; explicit, conscious memory.

Cerebral Cortex

The wrinkled outermost covering of the brain.

4 Lobes of the Cerebral Cortex

• Frontal

• Parietal

• Temporal

• Occipital

Frontal lobe

Manages voluntary movement, language production, and higher-level cognitive skills known as executive functions.

Parietal lobe

Processes sensory input like touch, pain, and temperature, and helps you understand your body’s position in space.

Temporal lobe

Processes auditory (related to hearing) information, comprehend language, encode long-term memories, and recognize complex visual stimuli like faces and objects.

Occipital lobe

Processes and interprets visual information sent from the eyes.

Motor cortex (within the frontal lobe)

Planning, control, and execution of voluntary muscle movements in the body.

It gives the largest amount of brain tissue to parts that require the most precise and fine motor control such as hands, fingers, lips, and tongue.

Somatosensory cortex (within the parietal lobe)

Processes physical sensations from all over the body, including touch, pain, temperature, and body position.

Left hemisphere of the cerebrum

• Controls right hand

• Spoken language

• Written language

• Mathematical calculations

• Reading

Right hemisphere of the cerebrum

• Controls left hand

• Music and artistic processing

• Emotion

• Processes the whole pattern recognition

• Facial recognition

Know the 3 main parts of the brain: the cerebrum, the cerebellum, and the brainstem.

Okay thanks!

Split-brain

It is where the corpus callosum, the main band of nerve fibers connecting the left and right hemispheres of the brain, is severed or severely damaged.

The two sides of the brain always work together as an integrated whole, except for…

Split-brain patients

Neuroplasticity

The brain’s ability to change, grow, and reorganize its structure and neural connections through a person’s life.

Corpus Callosum

A large, C-shaped bundle of white matter nerve fibers located deep in the center of the brain that connects the left and right hemispheres of the cerebrum.

Why does visual information-sharing not take place in a person with a severed corpus callosum?

The brain’s main communication bridge is gone, preventing the two hemispheres from passing each other visual data back and forth.

If we flash a red light to the right hemisphere of a person with a split brain, and flash a green light to the left hemisphere:

What will the person verbally report seeing?

Probably green because the left hemisphere is the one for language, and the right cannot use the left for verbal communication since it is split-brained, so only green. (I think)

EEG (Electroencephalogram)

Electrodes placed on the scalp measure electrical activity in neurons.

Symptoms of depression and anxiety correlate with increased activity in the right frontal lobe, a brain area associated with behavioral withdrawal and negative emotion (Thibodeau et al., 2006

Positron emission tomography (PET)

Tracks where in the brain a temporarily radioactive form of glucose goes while the person given it performs a task.

Monkeys with an anxious temperament have brains that use more glucose in regions related to fear, memory, and expectations of reward and punishment (Fox et al., 2015

Magnetic resonance imaging (MRI)

People sit or lie down in a chamber that uses magnetic fields and radio waves to provide a map of brain structure.

People with a history of violence tend to have smaller frontal lobes, especially in regions that aid moral judgment and self-control (Glenn & Raine, 2014)

Functional magnetic resonance imaging (fMRI)

Measures blood flow to brain regions by comparing continuous MRI scans.

Years after surviving a near plane crash, passengers who viewed material related to their trauma showed greater activation in the brain’s fear, memory, and visual centers than when they watched footage related to the 9/11 terrorist attacks (Palombo et al., 2015

Human Connectome Project

Diffusion spectrum imaging MRI methods

Where does neuroscience study people from?

From Western, Educated, Industrialized, Rich and Democratic (WEIRD) populations.