The Biological Bases of Behaviour

Neurons are

Specialized cells that make up the nervous system.

What are the 4 main parts of cells

The soma, Dendrites, Axon and Axon Terminals

What does the soma do

its the structures that keep the cell alive (Cell body)

Dendrites

Branches from cell body, receive signals

Axon

Conducts electrical impulses away from soma, (trunk like thing)

Axon Terminals

sends signals to other cells (Base of the truck)

Glial Cells

Support the neurons, make and move nutrients, removes toxins

How does the Glial Cells remove tocins

Through the blood-brain barrier (wall surrounding the brain making sure that toxins don’t get in)

What are the 2 basic functions of neurons

Generate Electricity and Release Chemicals

cells are stimulated and electrical charges ions flow across cell membrane creating

a reverse charge of resting potential and produces action potentials or neural impulses

Resting potential is

Cell is at rest with electrical resting potential

Action potential is when

cell is stimulated and electrical charges (irons) flow across cell membrane (depolarixation)

Restore resting potential

• Restore distribution of ions, cell at rest again 

• Sodium and potassium move at different times

• When the potassium channels open it makes the cell more negative  

Absolute refractory period

cells cannot fire, limits how often nerve impulse can occur, ensure that impulses only travel in a single direction

All-or-none law

Action potentials occur at a uniform and maximal intensity, or they do not occur at all 

The Myelin Sheath

A fatty, whitish insulation layer derived from glial cells during derived from glial cells during development to send information quicker It's not one continuance insulated tub

Nodes of Ranvier

places where the myelin is either extremely thin or absent, allows conduction to skip ahead

Synapses is where

axon terminals meet dendrites

Synaptic cleft is where

neurons communicate through as they do not make physical contact. they are functional not physical connections

What are Neurotransmitters

chemical substances that carry, messages across the synapse to either excite other neurons or inhabit their firing

What are the 5 stages of chemical communication

• Synthesis

• Storage

• Release

• Binding

• Deactivation

What is an Inhibitory Neurotransmitter

decrease resting potential of postsynaptic synaptic neuron; hyperpolarization (More negative)

What is an Excitatory Neurotransmitter

increase resting potential of postsynaptic synaptic neuron; may even fire. More positive

what are specialized Neurotransmitters

Different brain systems are sensitive to different transmitter

What does Glutamate do

Expressed in whole brain, Control of behaviours

Is glutamate Excitatory or inhibitory

Excitatory

GABA (Gamma-aminobutyric)

Expressed in whole brain, Control of behaviours, Especially anxiety and motor control

Is GABA Excitatory or inhibitory

Inhibitory

Acetylcholine

Function at synapses involved in muscle movement and memory

Is Acetylocholine Excitatory or inhibitory

Excitatory

Norepinephrine

Involved in learning, memory, wakefulness, eating. if you don’t have enough you can get depression and panic disorders

Is Norepinephrine Excitatory or inhibitory

Both depending on where it is in your body

Serotonin

Mood, eating, sleep, arousal

Is Serotonin Excitatory or inhibitory

Inhibitory (Mostly)

Dopamine

Voluntary movements, learning, motivation, pleasure

Is Dopamine Excitatory or inhibitory

Both

Endorphins

Insensitivity to pain (oversupply)

Hypersensitivity to pain, immune problems (undersupply)

Is Endorphin Excitatory or inhibitory

Inhibitory

What are the 3 types of neurons

Sensory Neurons, Motor Neurons, Interneurons Neurons

What do Sensory Neurons do

Carry input messages from the sense organs to the spinal cord and brain

What do Motor Neurons do?

Transmit output impulse from the brain and the spinal cord and brain

What does the Interneurons do

Perform connective or associative functions within the nervous systemWha

What are the 2 types of Nervous system?

The somatic Nervous system and the Autonomic Nervous system

what does the somatic nervous do

they are voluntary movements hey control the sensory and motor neurons Group together to form sensory and motor nerves Inside the brain, nerves are called tracts

what does the Autonomic nervous system do

involuntary movements, regulates internal environment, aspects of motivation, emotional behaviour and stress responses

What are the 2 types of Autonomic nervous systems

Sympathetic and Parasympathetic Nervous system

What is the Sympathetic Nervous system

Tends to act as a total unit (whole body), Something happens that causes your body to react Fight-or-flight

What is the Parasympathetic Nervous system

Slows down body processes, Returns body to a state of rest, Rest and digest

What is the central Nervous system

Contains the spinal cord and the brain. the spinal cord Connects parts of peripheral NS with the brain, Nerves enter and leave CNS primarial by spinal cord

What is spinal reflexes

Simple stimulus-response sequences, Triggered at level of spinal cord no brain involvement

What are the 3 different brain planes?

Horizontal, coronal and sagittal planes

What is the Horizontal planes in the brain

when you cut horizontally from front to back

What is the coronal planes in the brain

Ear to ear in slices

What is the sagittal plane in the brain

left to right, front to back vertically

What is the forebrain

a highly developed with numerous functions. Has Cerebral cortex, basal ganglia, limbic system, thalamus and hypothalamus

What is the cerebral cortex?

Outer layer of the cerebral hemispheres, involved in thinking and mental processes in the forebrain

What is the Basal ganglia

Collections of neurons crucial to motor functions in the forebrain

The limbic system

involves the hippocampus (Memory), the amygdala (Emotional response) and Nucleus Accumbens (Reward centre) in the forebrain

The Midbrain

Reflex actions and voluntary movements. Involves the Reticular formation, superior colliculi, inferior colliculi, Grey matter. red nucleus, and ventral region

What is the Reticular formation?

Involved in regulation of consciousness, Conscious awareness and control, Regulates sleep, wakefulness and attention, Extends into hindbrain and lower forebrain

Superior colliculi

Involved in vision (especially visual reflexes) in the Midbrain

Inferior Colliculi

Involved in hearing in the midbrain

Medulla

Apart of the hindbrain, controls hear activity and largely controls breathing, swallowing and digestion. all sensory and motor nerve tracts ascend from the spinal cord and descend from the brain

Pons

Apart of the hindbrain. Relay station for signals between higher levels of the nervous system and lower levels, Regulates sleep and dreaming, Controls muscles and glands in face and neck 

Cerebellum

Apart of the hindbrain, Controls bodily coordination balance, and muscle tone, Involved in procedural memory, Motor skills

Motor Cortex

Controls the muscles involved in voluntary body movements, apart of the Higher Functions of Cerebral Cortex

Somatic Sensory Cortex

Receives input: sensations of heat touch, cold and our senses of balance and body, similar location enhances sensory-motor interactions in the same body area Apart of the Higher Functions of Cerebral Cortex

Primary Auditory Cortex

Temporal lobe of both hemispheres Apart of the Higher Functions of Cerebral Cortex

Primary Visual Cortex

Occipital lob apart of the Higher Functions of Cerebral Cortex

Werbicke’s area

Involved in language and is apart of the Higher Functions of Cerebral Cortex

Broca’s area

Involved in normal speech production apart of the Higher Functions of Cerebral Cortex

Association Cortex

Found within all lobes of cerebral cortex, Involved in high-level functions, Appear “silent” because electrical stimulation does not give rise to sensory or motor responses, Apart of the Higher Functions of Cerebral Cortex

Right hemisphere is responsible for

Feelings, intuition, humor, Aesthetic, colour, relationships , rhythm, physical senses motor skills, Note: connects to the left side of the body

The left hemisphere is responsible for

Analytical thinking, rules, logic, Structure, mathematics, planning, Speech, language, time. Note: Connects to the right side of the body

Visual Lateralization

Left visual field - processed in right hemisphere of brain 

Right visual field- processed in left hemisphere of brain

Hemispheric Lateralization

Hemispheres often communicate across corpus callosum, Corpus callosotomy is when the corpus callosum is severed, Results in “split-brain” patients

Separating the hemispheres 

Corpus callosum-  Bridges hemispheres, Transfer of information from one hemisphere to the other

CT- Computed tomography

Builds a picture if the brain based on the differential absorption of X-rays , Reveals gross features of the brain, Quick cheap photo of brain that isn't very detailed

PET - Positron Emission Tomography

Builds a picture of the brain using trace amounts of short-lived radioactive material, Is used to see what part of the brain is currently activate but you cant see the structure of the brain, Maps functional processes in the brain

Structural MRI - Functional Magnetic Resonance Imaging

Builds a picture of the brain using strong magnetic field, High def photo of the brain but takes way more time and is very expensive, Reveals features and structure of the brain, Used in conjunction with fMRU to measure structural integrity

fMRI - Functional Magnetic Resonance Imaging

Detects changes in blood oxygenation and flow, Expensive PET scan can do both MRI and fMRI at the same time, Tied to neural activity, High activity = high oxygen use and high blood flow

EEG - Electroencephalography 

Measures electrical activity via electrodes, Can be inter- or intra-cranial, Electrodes either on or in the skull, Very good time resolution (milliseconds)