5A and 5B - role of the brain in mental pocesses and behaviour Flashcards
What is the brain–heart debate?
The question of whether our thoughts, feelings, and behaviours originate from our brain or our heart.
Brain- Alcmaeon 475BCE
Heart -Aristotle
Empedocles- Blood
What did Galen conclude about the relationship between the brain and behaviour?
Injury to the head and brain affected behaviour, while injuries to the heart did not.
What is the mind–body problem?
The extent to which the mind and the body are the same or separate things.
What is Dualism
Rene Descartes suggested that the mind and body are separate entities.
Pineal Gland- A structure where the mind and body interact
What is phrenology?
The study of the shape of the skull as an indicator of the extent of one’s mental faculties and character traits.
Franz joseph Gall
- believed that each part of the cerebral cortex linked to specific mental faculties and traits.
- The idea of localization of brain functions
What are the meninges?
Three layers of membrane that protect the brain.
What is the significance of localization of function?
It refers to the idea that specific areas of the brain are responsible for specific functions.
What is functional magnetic resonance imaging (fMRI)?
measures brain activity by measuring oxygen consumption by cells
Pros- no radiation
Detailed/accurate c/w PET
What did Hippocrates and Herophilus believe about mental processes?
They believed that mental processes and emotion arose from the brain.
What are the protective layers surrounding the brain?
Skull, meninges, and cerebrospinal fluid (Cushions the brain from hard knocks)
What is mass action?
Involvement of large areas of the brain functioning together to carry out complex functions
What is ablation?
The surgical removal or destruction of brain tissue by lesioning or using electrodes.
Who was Pierre Flourens and what was his contribution to brain research?
A French physiologist who performed brain ablation on animals to study brain function.
- establish The idea of ‘holistic’ brain function.
What is equipotentiality?
The ability of healthy areas of the cortex to take over the functions of injured parts.
What did Karl Lashley investigate in his brain experiments?
The parts of the brain responsible for learning and memory.
- Learning and memory are distributed throughout the brain rather than localized in a single area.
What does the hippocampus do?
Involved in the formation of new memories and learning.
What is lesioning?
The creation of small areas of damage in the brain.
What are electrodes?
small wires to electrically stimulate biological tissues or measure electrical activity
Who were Gustav Fritsch and Eduard Hitzig?
German doctors who discovered that stimulating the motor cortex in a dog caused movements on the opposite side of the body.
What was Wilder Penfield known for in brain research?
His work in electrically stimulating the human brain to locate areas contributing to epileptic seizures.
What are the two categories of neuroimaging techniques?
Structural and functional.
What does CT stand for and what does it do?
Computerised tomography; it combines x-ray images to create cross-sectional images of the body.
- structural
- may use ‘contrast’
- tumor location
- stroke aftermath
- dementia, Alzheimer’s…
What does MRI stand for and what does it do?
Magnetic resonance imaging diagnoses structural abnormalities in the brain using magnetic fields.
- more detailed/ clearer than CT
- find cancer/tumor
- stroke aftermath
- MS and neurological disorders
What does PET stand for and what does it measure?
Positron emission tomography; it measures brain activity and function by observing glucose use in brain.
- use colour code
- use radiotracer
-
Describe two pieces of technology that provide information about brain function.
- fMRI (functional Magnetic Resonance Imaging)
- EEG (Electroencephalogram)
Why are brain experiments involving direct electrical stimulation virtually unheard of today?
Ethical concerns and advances in non-invasive techniques
Direct stimulation poses risks and ethical dilemmas.
What is a dendrite
A dendrite is a projection of a neuron that typically branches from the cell body.
-receives info
- dendritic spines have role in learning & memory
What is the soma or cell body in a neuron?
Receives information from dendrites and contains the nucleus (genetic code)
-coordinating center of nerve cell
The soma coordinates the activities of the neuron.
What are axons?
a fibre that transmits nerve signals
axon terminals:
- structures at the end of the axon that store and release neurotransmitters
What are nerve impulses?
an electrical message that travels along the
axon of a neuron
What is a synapse?
the point of communication between two
neurons or between a neuron and a
target cell, such as a muscle or gland cell
What is myelin?
A fatty substance that covers axons and speeds up information transmission
Myelin sheath prevents signal leakage during transmission.
What is a neurotransmitter?
A chemical produced by a neuron that carries a message across the synapse to another neuron
Neurotransmitters are crucial for communication between neurons.
What does the central nervous system (CNS) comprise?
The brain and spinal cord
The CNS processes information and coordinates responses.
What is the main function of the spinal cord?
Carries sensory and motor information between the brain and the periphery’
sensory
-Information detected by sensory receptors from the internal and external environment
motor
-Information transmitted from the CNS to organs, glands, and muscles to bring about bodily actions
It acts as a transmission pathway for information.
What is the primary function of the peripheral nervous system (PNS)?
To relay information from sense organs, muscles, and glands to the CNS
- Through sense organs such as eyes, ears, and skin.
This allows the CNS to make decisions regarding bodily responses.
What does the somatic nervous system do?
Carries sensory information to the CNS and transmits information from the CNS to the body
It involves sensory and motor neurons.
What does the autonomic nervous system do?
Connects the CNS to the organs and glands of the body
What response does the sympathetic nervous system activate?
Fight-or-flight-or-freeze response in dangerous or stressful situations
This response prepares the body for stressful situations.
What does the parasympathetic nervous system activate?
the rest and digest response after a dangerous or stressful situation has passed.
What is the hindbrain?
Comprised of:
* Cerebellum
* Medulla oblongata
* Pons
which is involved in supporting vital bodily processes, such as breathing and sleep.
What is the role of the cerebellum?
Coordinates movements and is involved in learning and memory
- damage can lead to issues with balance, challenges with detecting visual motion and loss of muscle coordination
It ensures smooth execution of voluntary movements.
What is the pons?
Acts as a bridge between the cerebellum and cerebral cortex.
- damage can lead to balance and coordination problems, hearing loss or loss of sensation in one side of the body
- located above the medulla oblongata and below midbrain
- involved in sleep, arousal, facial expressions and hearing
It is located above the medulla oblongata.
What is the medulla oblongata?
Its involved in the autonomic functions of the
body, such as heart rate and breathing
- damage may cause death or sever health problems
- located at the base of the brain (where brainstem attaches to spinal cord)
What is the midbrain?
Connects upper and lower brain areas, involved in auditory, visual processing, motor control, pain inhibition and reward-based learning patterns
- at the topmost part of the brainstem
It is also important for motor control and pain inhibition.
What is the substantia nigra?
one of the largest collections of dopamine-producing neurons in the brain
-in midbrain
- dopamine is a neurotransmitter involved in movement and coordination
It is associated with movement and coordination.
What is the reticular formation?
plays a role in maintaining arousal, consciousness and motor control
- in the midbrain
- connected to a network that runs from hindbrain to forebrain
Contains reticular activating system (RAS)
- an area in the midbrain that is responsible for alertness and awakening
- damage will disrupt sleep-wake cycle and may result in coma or vegetative state
What is the forebrain?
Comprised of:
* Cerebrum
* Thalamus
* Hypothalamus
* Pineal gland
* Limbic system
and which is involved in coordinating brain activity
What is the hypothalamus?
connects the hormonal and nervous systems via pituitary gland
- regulates body’s internal environment
- helps the body to maintain homeostasis through the control of body temp, hunger thirst and sleep
- size of almond
- part of limbic system
- damage may lead to issues with controlling body temp, continuously feeling hungry after eating and problems sleeping
What is the limbic system?
interconnected brain structures in the centre -of the forebrain, next to the midbrain,
- play a role in emotions, behaviour control and the formation of long-term memories
What is homeostasis?
The condition of maintaining a stable internal environment of the body necessary for survival.
What is the thalamus?
Relays sensory information (except smell) to the cerebral cortex for processing
- located in forebrain, near the center
- damage may include numbness, hypersensitivity, visual field loss and decreased tatse
- plays role in attention and focus
- filters sensory info received
It also regulates arousal and attention.
What is the cerebrum?
The largest part of the forebrain, responsible for directing conscious motor activities and processing sensory information.
- joined by corpus callosum
What is the cerebral cortex?
the thin layer of neurons covering the outer region of the cerebrum
- extensively folded
- two hemispheres
simplified into three areas
- motor
Initiate voluntary movement.
- sensory,
Involved in receiving and processing sensory information. - association
Integrate information from multiple brain regions for complex cognitive processes.
What is hemispheric specialization?
When one side of the brain controls a specific function that the other side cannot control
What is frontal lobe?
Important in planning, sequencing, and executing voluntary motor activity.
- upper forward half og both hemispheres
- Prefrontal cortex
- association area involved in various other
brain functions, such as reasoning, problem-solving, emotional regulation, attention,
symbolic thinking, and initiating and inhibiting behaviours - once sequence has been planned, it is passed to the premotor cortex and primary motor cortex
- Premotor cortex
- prepares the sequence of
movements and sends this information to the primary motor cortex - Primary motor cortex
- responsible for movements associated with
different areas of the body.
What is Broca’s area?
Contributing to clear and fluent speech by coordinating muscle movements.
- next to primary motor cortex
- sends and receives messages from other areas of the brain
Damage to Broca’s area leading to difficulty in producing speech while understanding language
What is the temporal lobe?
Significant in receiving and processing sounds, memory, emotional responses, and some visual perception.
primary auditory cortex
-assists us in identifying
and responding to sound,
What is Wernicke’s area?
A specialized area of the left temporal lobe critical for understanding the sounds
involved in speech
- speech production
Damage to Wernicke’s area leading to difficulty in understanding language while speaking fluently but nonsensically
What is the parietal lobe?
Involved in spatial awareness, spatial reasoning, attention, and processing somatosensory information.
Primary somatosensory cortex
- receives and process’s sensory information from a range of body areas
- Areas that are more sensitive are devoted more area in the cortex
What is the occipital lobe?
involved in receiving and processing
information related to vision
primary visual cortex
- receives and processes information from visual sensory receptors in the retina of both eyes
What are the components of the brainstem?
- Midbrain
- Pons
- Medulla oblongata
Each component has specific roles in regulating vital functions.
Outline how the brain is connected to the spinal cord.
The brain sits on top of the spinal cord, with nerve fibers running from the spinal cord into the brain
This connection is crucial for communication between the brain and body.
What separates the two cerebral hemispheres?
Longitudinal fissure
What do the terms gyri and sulci refer to?
Bumps and grooves on the brain
What are the three main functions of the nervous system?
- Receive information
- Process information
- Coordinate a response to information
What is the fight/flight/freeze response?
An emergency system activated when the organism feels threatened, preparing the body for action.
What are the three types of neurons?
- Sensory Neurons
Receive and carry sensory information from the sense organ to the CNS. - Motor Neurons
Carry messages from the CNS to different parts of the body. - Interneurons
Act as a link between sensory and motor neurons, relaying information.
What parts are included in a neuron?
- Dendrites
- Nucleus
- Axon
- Soma
- Myelin sheath
- Axon terminals
- Terminal buttons
What is a homunculus?
Represents body parts in terms of their relative size on the primary motor cortex or somatosensory cortex
What does the left hemisphere specialize in?
Language and analytical thought
What does the right hemisphere specialize in?
Non-verbal processing
What is the Wada test used for?
To determine which hemisphere controls speech and language by anesthetizing one hemisphere
