The Brain Flashcards
What are the 3 main regions of the brain?
Forebrain, Midbrain, Hindbrain
The Forebrain
The Midbrain
- Located between the Forebrain and the Hindbrain.
- Plays an important role in relaying information between regions and CNS.
The Hindbrain
- Located at the base of the brain.
- Controls autonomic functions and reflexes e.g. breathing
- Contains the cerebellum
Cerebellum
It helps coordinate muscle movements allowing for muscle memory. It helps maintain balance and posture.
It encodes and temporarily stores implicit memory related to movement.
The Reticular Formation
Controls physiological arousal and focuses attention by filtering sensory information.
It directs the messages to the correct part of the brain.
Basal Ganglia
Involved in procedural memory, planning and control of motor skills, and encoding implicit memories related to well-practised movement sequences.
Cerebrum and Central Cortex
The cerebrum is the largest and most developed part of the brain. It is responsible for most of our actions. It is divided into two hemispheres. The outer layer of the cerebrum is the cerebral cortex, which coordinates sophisticated mental processes and performs complex functions.
Amygdala
Helps to encode and store the emotional component of implicit memories.
If damaged it causes:
- impaired ability to express and interpret emotions
- unable to learn a fear response
- fearlessness
Hippocampus
Encodes, sorts and transfers short-term memory into long-term memory.
It doesn’t store information but plays a role in language memory.
If damaged it causes:
- Didduclty forming and consolidating memories
- Shrinkage is the first sign of Alzheimer’s
Contralateral Organisation
The left hemisphere controls the right side, and vice versa
Left Hemisphere Verbal Functions
It is responsible for the recognition and use of language and speech.
EG. reading, writing, speaking
Left Hemisphere Analytical Functions
Breaking down a task into key parts, abstract thinking.
EG. following/reading a recipe.
Right Hemisphere Non-Verbal Communication
Functions that aren’t dependent on language skills.
EG. Spatial/visual thinking, recognising faces/patterns.
Right Hemisphere Emotional Intelligence
Recognising facial cues to determine emotion, and understanding sarcasm, jokes and irony.
EG. determining the meaning behind a raised eyebrow.
The Four Regions of the Neocortex
FPOT:
Frontal, Parietal, Occipital and Temporal lobes
The Frontal Lobe
Planning, sequencing and executing voluntary motor activity, responsible for clear and fluent speech production. Regulates emotions and personality.
Regions of the Frontal Lobe
Prefrontal Cortex, Premotor Cortex, Primary Motor Cortex, and Broca’s Area.
Prefrontal Cortex
Coordinates complex mental processes, recognises when a motor movement needs to happen and plans it. Sends info to the premotor cortex.
Premotor Cortex
Receives info from the prefrontal cortex and processes this into a sequence of motions. Sends the sequence to the primary motor cortex.
Primary Motor Cortex
Initiates voluntary motor movements. Receives the sequence and signals to the cerebellum to relay this info to the skeletal muscles which carry out the movement.
Broca’s Area
Responsible for the production of speech, only in the left frontal lobe. Damage to this area causes Broca’s Aphasia where people can understand but can’t produce speech.
Parietal Lobe
The region behind the frontal lobe, is comprised of sensory and association areas. Involved in spatial awareness, spatial reasoning and receiving and processing somatosensory information.
Primary Somatosensory Cortex
Receives and processes somatic (bodily) sensory information (touch, temperature, pain).
Helps us understand the body’s position in space so we can coordinate our senses and movements.
Occipital Lobe
The rearmost lobe is comprised of sensory and association areas. Plays a crucial role in vision.
Primary Visual Cortex
Receives and processes visual information to enable us to perceive and interpret the visual information.
Temporal Lobe
The lowest lobe receives and processes sound from the ears, as well as memory and emotional responses to sensory info.
Plays a critical role in understanding the sounds involved in speech.
Regions of the Temporal Lobe
Primary Auditory Cortex, Wernicke’s Area
Primary Auditory Cortex
Receives and processes auditory information.
The PAC in the left hemisphere processes verbal sounds, such as spoken words.
The PAC in the right hemisphere processes non-verbal sounds, such as music.
Wernicke’s Area
Responsible for the comprehension of speech and involved in the production of meaningful and coherent speech.
Located only in the left temporal lobe.
(only affects verbal sounds)
Wernicke’s Aphasia is when a person struggles to interpret or produce meaningful and coherent language.
Neuroplasticity
Refers to the nervous system’s ability to change its structure and function due to experience or environmental stimulation.
Neuron
- Building blocks of our nervous system
- Enable communication around the body and are vital in processing.
- ~86 Billion different neurons.
- Three types, Sensory, Interneurons and Motor
Sensory Neurons
They carry sensory signals.
And are connected to sensory
receptors in the body and carry afferent
information towards the spinal cord.
Interneurons
They are in the spinal cord
that connect sensory and motor neurons by
relaying information between the two.
Motor Neurons
Nerve cells that
transmit motor impulses from the spinal cord
to the skeletal and smooth muscles.
Dendrites
Receives neuronal messages
Myelin Sheath
Insulates and protects from mix-ups.
Axon
Transmits electrical impulses.
Axon Terminal
Sends neuronal messages to the next neuron.
Synapse
Includes the synaptic gap and the dendrites and axon terminals surrounding the synaptic gap.
Synaptic Plasticity
Changes in the synapse.
Long-term potentiation,
Where connections are strengthened relatively permanently by the repeated activation of a neural pathway.
Long-term depression,
Where connections are weakened relatively permanently through repeated low-level activation.
Developmental plasticity
Happens in response to aging and learning through maturing.
Factors: synaptogenesis,
and synaptic pruning.
Adaptive plasticity
Happens due to a need to adapt to best suit and environment.
Factors: Sprouting and Rerouting
Synaptogenesis
Where more synapses form between axon terminals and dendrites. Happens the most during infancy.
Synaptic Pruning
The elimination of underused synapses. The brain doesn’t start pruning until about 2-3 years old. Happens the most during adolescence. “Use it or lose it”
Sprouting
The ability of a neuron to form new branches on dendrites (spines) or axon terminals (filigree appendages).
Rerouting
The ability of a neuron to form a new connection with another undamaged neuron.
Mental Stimulation
Any activity that involves processing information e.g. learning an instrument.
This prevent synaptic pruning.
Diet
Must be balanced and avoid coffee and alcohol.
Exercise
Should be at least an hour everyday. Increases blood flow to the brain.
Social Support
We need people to interact with.
Risk Reduction
Wear seatbelts and helmets and minimise stress.
Synaptic Gap
The gap between the dendrites and axon terminals.
ABI
An acquired brain injury refers to types of brain injuries obtained after birth.
BIO: Changes in senses, speech deficits, loss of motor skills and headaches
PSYCHO: Struggles with; Processing info, understanding language, aggression, mood swings, concentrating and focusing.
SOCIAL: Lack of self-awareness, increased isolation and loss of relationships.
Two types; TBI and NTBI
TBI
A traumatic brain injury is damage to the brain by EXTERNAL force.
e.g. car accident, physical assault, sporting head knocks and shaken-baby syndrome.
NTBI
A non-traumatic brain injury is damage to the brain caused over time by INTERNAL force.
Alzheimer’s Disease
Is a form of dementia. It is a degenerative NTBI and it progressively destroys neurons in the brain.
Phineas Gage
An iron rod passed through Gage’s frontal lobe. His personality was affected (PYSCHO) and his friends said that ‘he was no longer Gage.’ (SOCIAL)
He began having seizures afterwards and died from one twelve years after the accident. (BIO)
Signs of Alzheimer’s
The first sign is reduction of the hippocampal volume.
Other signs include an increase in Amyloid Plaques and Neurofibrillary Tangles.
Amyloid Plaques
Everyone has it but Alzheimer’s patients cannot break it down leading to it collecting on nerve endings and blocking signals.
Neurofibrillary Tangles
Twisted strands of the tau protein found in dead/dying nerve cells form into clumps and block substance transfer leading to brain cells dying
