Biological Psychology

History of the brain

The brain has evolved over the past
few million years, it has chronologically
grew starting with:

1. Hind Brain

2. Limbic System

3. Neo Cortex

Ancient History

During this era they pulled out the brain through the nose; piece by piece they took it out with a hook

Created holes in the skull to remove the "idiot stone"

Father of modern medicine

Thought the brain told what us to do

Thought the brain was a hot and cool radiator for the body

Early Physician experiments

170 BCE

1500

1664

1929

EEG is is a test used to find problems related to electrical activity of the brain. An EEG tracks and records brain wave patterns

1934

Abnormalities and Traumas

Key Case Studies

He was an American railroad construction foreman remembered for his improbable survival of an accident in which a large iron rod was driven completely through his head, destroying much of his brain's left frontal lobe.

The soma is the body of the nerve cell

Information holder

The dendrites are the receivers that act as receptors for signals travelling from other neurons, carrying information toward the main body of the nerve cell.

Recievers

The axons are the senders that send out information to the other cells and is covered in a thick tissue called myelin sheath.

Sender

Synapses

The more these neurons connect with eachother, the stronger the synaptic connection becomes. This creates strong neaural pathway

When one cells axon connects with another cells's dendrites they create a connection called a synapse or synaptic connection

Neurons communicate when two neurons connect with one another

1.Reuptake channels, the axon terminal of the cell reabsorbs many neurotransmitter molecules; the axon then recycles them to be used again

2.The enzymes present in the synaptic cleft destroy some neurotransmitter molecules

3.Still other molecules diffuse out of the cleft and are carried away as waste material by the cerebrospinal fluid

Neurotransmitters are chemicals in the brain that are generally either excitatory or inhibitory, which means they can either increase or decrease the likelihood of a neuron firing.

Neurotransmitters fall into 3 catagories

Amines

Dopamine - two major roles are to control conscious motor activity and enhance pleasurable feelings in the brain’s reward system (anticipated reward).

Serotonin- is a mood enhancer, but affects mood by calming rather than stimulating. Depression drugs inhibit the reuptake of serotonin thus increasing it’s effect.

Neuropeptides are lumped together loosely under a generic name Endorphins

Endorphins- creates a feeling of euphoria which helps as a pain killer.

Opioids are an addiction and depression

oxacillin and heroine

Psychoactive drugs interact with neurotransmitters meaning they affect mood, arousal or behaviour. They often allow us to predict how they'll affect us psychologically

opiates such as codeine function as agonists, which means they increase receptor site activiey. Reduce our emotional response to painful stimuli by binding wiht opiod receptoprs and mimicking endorphoins

Our brains have two types of cells. There are the glial cells and the neurons.

The glial cells are also known as neuroglia. Their function is to guide neurons towards making connections, promote neuronal health, and influence the functioning of the brain. The glial cells do not make their own connections.

The neurons are commonly found primarily in the brain and spinal cord (the central nervous system- CNS). Our bodies are capable of generating new neurons, but neurons do not regenerate in the same way as any other cells.

Neurons communicate through chemical and electrical signals. When the neauron becomes stimulated it recieves excitatory signals from another neuron. This results in a neauron being positively charged for a brief period of time known as action potential

Have the capacity to differentiate into a more specialzed cell

They can genetically engineered to provide therapy, providing the patient with replacement genes

Researchers can implant stem cells into the nervous system and induce them to grow and replace damaged cells

oriiginate in embryos

The pons (center area)- meaning bridge, acts as bridge from the medulla oblongata to the other brain regions, responsible for motor control and sensory analysis, and midbrain (upper end)- processes vision, hearing, and eye movement, the cerebellum- the role is to coordinate movement and balance

The medulla oblongata (the lower end)- where the spinal cord meets the brain stem, responsible for basic bodily functions such as heartbeat and respiration,

The midbrain processes vision, hearing and eye movement

Prefrontal Cortex is not fully developed until 25 years of age (on average). This part of the brain is newest evolutionarily speaking and responsible for impulse control and executive functions.

Limbic System

The pituitary gland controls the functions necessary for maintaining the normal state of the body homeostasis

Plays a role in regulating sex drive, sleep, agressive behaviour and pleasure.

Holds the memories from your immediate past and dispatches the memory to the cortex, where it is stores in longterm memory. Once a memory is fully encoded into long term memory, it would appear that the hippocampus is no longer needed for it to be retrieved

Two walnut sized structures joined by a bridge. The thalamus has been said to be the gateway to the cortex. This is the area of the brain that all sensory input goes to before it is sent off to the appropriate region of the brain

Two small almond, it is considered the brains alarm system

Plays a major role in the control of emotions. The amyglda forms unconscious memories based on emotional responses

An evolutionary mechanism that triggers our mind and body to respond to stressful and/or life threatening situations

Left Hemisphere

Responsible for the academic,
verbal and analytical things

Right Hemisphere

Responsible for the creative,
artistic and emotional things

The right hemisphere governs the
left side of the body and the left
hemisphere governs the right side
of the body

Four Neuroimaging techniques

Stands for Positron Emisson Tomography

Views the structure of the brain to
see which part if the brain is active
during specific task or events

During the PET scan

The part of the brain that is showing
the greatest activity shows up as red,
white and yellow

The part of the brain that shows
less activity is green, blue and puprle

Limitations of a PET Scan

This is not recommened for children or adults in great doses

Delay in reading the functionsing
of the brain by 40 seconds

The PET scan does not directly
show the specific area in which
the activity is occurring

Stands for Magnetic resonance imaging

A more detailed 3D image of the
brain and gives a percise mapping
of the physical shape of the brain

Looks at the structure of the
brain, but gets a more details
pictures of the brain tissue

Useful for quick assesing of brain injuries

Looks at the structure only

Can also be any part of the body, not just the brain

A series of x-rays of the head are
taken from many different directions

Stands for Computerized technology

Stands for Functional Magnetic resonance imaging

Uses changes in blood flow to
generate images that show brain
activety and performance

Looks at the structure of the
brain and their functions