Bipsychology

The influence of biological structures on behaviour:

The divisions of the nervous systems

Central nervous system (CNS)

This system compromises of the brain and the spinal cord and its main job is to maintain life.

Peripheral nervous system (PNS)

This system includes all the nervous system throughout the rest of the body. It transmits messages to the whole body from the brain and vice versa. It has two divisions: the somatic and the autonomic system.

The somatic system

Transmits information to and from senses and to and from the central nervous system.

The autonomic system

Transmits information to and from the internal organs to sustain life processes. It is divided into sympathetic and para

sympathetic nervous system

which generally increases bodily activities

parasympatheitc nervous system

generally maintains or decreases bodily activities

neurons

receive information and transmit it to other cells. There are three main types of neurons all of which have a different role to play.

Synaptic transmission

The process by which nerve impulses are carried across the small gap, the synapse, between one neuron and another. The nerve impulse is an electrical signal which is carried by chemicals called neurotransmitters.

Excitatory potentials

Increase the chance of a neuron firing

Inhibitory potentials

Decrease the chance of a neuron firing

The endocrine system

Has a series of glands which release chemicals throughout the body via the blood and other bodily fluids. This communicates messages to the organs of the body.

Pituitary gland

Some of the hormones released are important for regulating the endocrine system

Adrenal gland

An important part of the fight or flight response as it facilitates the release of adrenaline

Testes

They facilitate the release of testosterone

Ovaries

They facilitate the release of oestrogen and progesterone

Hypothalamus

A part of the brain which is located in the center of the brain and deals with basic survival functions

Adrenal gland

The gland in the adrenal system that releases adrenaline

The fight or flight response

is generated from the autonomic nervous system, specifically the sympathetic branch. it is a reflex response designed to help individuals to react quicker than normal and facilitates optimal functioning so they can fight the threat or run away from it

step 1 of fight or flight response

the hypothalamus recognizes that there is a threat and sends a message to the adrenal gland

step 2 of the fight or flight response

the adrenal gland specifically the adrenal medulla triggers the release of adrenaline

step 3 of the fight or flight response

Adrenaline is released to the endocrine system and noradrenaline in the brain which prompts physical changes in the body.

increased heart rate

to speed up blood flow to vital organs and improve the spread of adrenaline around the body

faster breathing

to increase oxygen intaje

muscle tension

to improve reaction time and speed

pupil dilation

to improve vision

production of sweat

facilitate temperature regulation

reduced functioning of digestive and immune systems

to save energy for prioritised functions such as running

neurons

recieve information and transmit it to other cells. they are essential parts in a massive communication system within the body

sensory neuron

these neurons tell the rest of the brain about the external and internal enviornment by processing information taken by the senses

relay neuron

relay neurons carry messages from one part of the CNS to another. They connect motor and sensory neurons

motor neuron

carries signals from the CNS which help both organs and muscles

synaptic transmission

the process by which nerve impulses are carried across the synapse between one neuron and another. The nerve impulse is an electrical signal which is carried by chemicals called neurotransmitters. This occurs at high speed

excitatory potentials

make it more likely for the neuron to fire

inhibitory potentials

make it less likely to fire and if the message is likely to be stopped at the post synaptic neuron it is called an inhibitory synapse

localisation

in terms of the brain this means the part of the brain in which a function is carried out

hemispheric lateralisation

when one hemisphere carries out a particular action

what hemisphere is language processing mainly performed in

left hemisphere

what areas are found in the left hemisphere

brocas area and wernicke's area

what hemisphere is particularly dominant for recognising emotions in others and spatial information

the right hemisphere

motor cortex

is particularly important for complex movement such as coughing, gagging and crying

pre

frontal cortex

somatosensory centres

referring to the sensation of the body. It perceives touch and lies next to the motor cortex in the brain

primary visual cortex

is in the occiptal lobe which is at the back of the brain . This is seen to be the main visual centre

primary auditory cortex

the human brain has two primary auditory cortices, one in each hemisphere. it receives information from both ears via two pathways that transmit information about what the sound is and its location

where are the language centers situated

the left hemisphere

broca's area

Broca correctly identified that the left temporal lobe was responsible for the production of speech

wernicke's area

This is a separate area of language processing which seems to have a specific function

corpus callosum

the link between the hemispheres

split brain

describe the result when the corpus callosum connecting the two hemispheres of the brain is severed to some degree.

plasticity

is the ability to replace the function lost by autonomical damage. A cell body can never be replaced, but axons in some cases can.

1 wayy the body can replace axon function in the brain after trauma

axon sprouting

increased brain stimulation

work by takasuru demonstrated that if the undamaged hemisphere is stimulated, recovery from a stroke can be improved

axon sprouting

when an axon is damaged its connection with a neighboring neuron is lost. in some cases other axons that already connect with that neuron will sprout extra connections to the neuron.

functional recovery of the brain after trauma

due to anatomical compensation brought about by intensive rehabilitation

factors that affect the functional recovery of the brain after trauma

age, gender, perseverance, physical exhaustion stress and alcohol consumption

fMRI's

is a technique of brain scanning that uses a magnetic field and radio signals to monitor the blood flow in the brain

EEG (electrocenephalogram)

a method of measuring brain activity using electrodes which can vary from 2 to one hundred. Electrodes measure the activity of the cells immediately under the electrode, so using more gives a fuller picture

ERP's ( event related potentials)

a method of measuring brain activity in response to a stimulus (using the same equipment as EEG)

post mortem examinations

are when a persons body including the brain is examined after they have died. they can be used to see where the damage has occurred in the brain and how that might explain behaviour exhibited by the individual prior to death