YEAR 11 PSYCH UNIT 1 AOS 2 - KK1 & KK2

BRAIN VERSUS HEART DEBATE

a historical debate as to whether the heart or the brain is responsible for mental processes, such as thought, emotion, and behaviour.

dualism

•The belief that the human mind and body are separate and distinguishable from one another.

monism

•The belief that the human mind and body are together a singular, complete entity.

PHRENOLOGY

the study of the shape and size of the human skull to determine personality and mental functioning.

ablation

an irreversible process that involves the surgical removal, destruction, or cutting of a region of brain tissue.

brain lesioning

the practice of inducing and/or studying the effects of damage to an area of the brain.

Difference between ablation and brain lesioning:

• Ablation refers to the removal of parts of the brain, whereas lesions are damages to the brain.

split brain research

•Sperry and Gazzaniga (1960’s) worked with patients who had undergone ‘split-brain surgery’, meaning they had had their left and right brain hemispheres separated by cutting the nervous tissue that connected them, known as the corpus callosum.

•The surgery was conducted to prevent the patients’ epileptic seizures which had proven to be severe and uncontrollable.

Split-brain patients were situated behind a screen with a black dot in the centre on which they focused their eyes.

Words and objects were then projected on either the left or right side of the dot. Words and objects in the left visual field are sent to the right side of the brain for processing and vice versa.

NEUROIMAGING

refers to a range of techniques that are used to capture images of the brain’s structure, function, and activities.

structural neuroimaging

techniques produce images of the brain’s structure and composition.

•Provide information on what the brain looks like.

functional neuroimaging

•use images to show us the brain’s activity and functions, as well as the stucture.

•Provide information on brain activity.

Computerised tomography (CT)

TYPE OF STRUCTURAL NEUROIMAGING

•involves taking continuous two-dimensional x-ray images of the brain which are then stacked to create a comprehensive three-dimensional image of the brain.

•an individual ingests a dye called ‘contrast’ which allows their brain to be visible in scans.

Benefits

•Enables the detection of hemorrhages, blood clots, cancer, and the loss of brain mass that can reflect disorders.

Limitations

•Aren’t as detailed as images from other neuroimaging techniques

Magnetic resonance imaging (MRI)

TYPE OF STRUCTURAL NEUROIMAGING

•Uses magnetic and radio fields to take detailed two-dimensional and three-dimensional images of the brain.

BENEFITS

Produce more detailed, coloured images of the brain than the images produced by CT scans.

Limitations

•Due to relying on magnetic fields, an MRI cannot be used on a person with internal screws, pacemakers, or other similar devices.

Positron emission tomography (PET)

FUNCTIONAL

take coloured images of the brain, showing its functional activity by tracing the levels of a radioactive substance in the brain.

patient being injected with a radioactive glucose solution; this essentially lights up active areas of the brain.

•Patients are required to perform an activity, at which point a doctor will be able to determine whether the brain activity is ‘normal’ or not.

Functional magnetic resonance imaging (fMRI)

•Uses magnetic and radio fields to take two and three-dimensional images of the brain and record its activity levels.

•Tracks oxygen levels rather than glucose levels

brain

a component of the central nervous system that coordinates mental processes and behaviour and regulates bodily activity.

divided in 3 regions

forebrain midbrain hindbrain

brain stem

•extension of the spinal cord that is made up of the medulla, pons, and midbrain.

is part of the midbrain and some of the hindbrain

hind brain

is responsible for coordinating basic survival functions, including movement, breathing rate, heart rate, and digestion.

•contains brain structures that developed earlier, and are responsible for basic, instinctive, lower-level functions.

structures of hindbrain

pons

medulla

cerebellum

cerebellum

communicates motor information to skeletal muscles so like balance/posture and tying shoe laces - muscle memory

far back of hindbrain

pons

•It connects and relays neural messages between the medulla and the midbrain.

•It also has an important role in regulating the respiratory system and controlling sleeping, dreaming, and waking.

•The pons is also involved in various involuntary behaviours, such as blinking.

The Pons is located between the Midbrain and the Medulla, and in front of the Cerebellum

medulla

regulates autonomic processes, such as respiration, heart rate, blood pressure, and digestion.

It also has an important role in initiating reflexive actions

midbrain

processing sensory information

coordinating motor movement

regulating sleep and physiological arousal.

reticular formation

•filters neural information that is travelling to the brain and direct these messages to various areas and structures of the brain.

•regulates sleep, wakefulness, and consciousness.

•regulates physiological arousal and alertness through the reticular activating system.

forebrain

is involved in sophisticated mental processes and complex functions.

3 main structures are thalamus hypothalamus and cerebrum

thalamus

•All incoming sensory information relating to vision, hearing, taste, and touch, (not smell) is analysed by the thalamus and then relayed to higher brain areas for further processing

alertness

hypothalamus

•maintains optimal biological functioning including hormone levels, hunger, thirst, body temperature, and blood pressure.

cerebrum

•The cerebrum is a large expanse of brain matter and the largest structure in the human brain.

information, and initiating voluntary motor movement.

cerebral cortex

•The cerebral cortex is the outer layer of the cerebrum that covers the brain.

•Mental processes, including language, sensation, perception, problem-solving, judgement.

frontal lobe

•The frontal lobe is the largest and frontmost lobe of the cerebral cortex.

Problem solving

Initiative

Movement

Planning

-Prefrontal cortex

      -Premotor cortex

      -Primary motor cortex

      -Broca’s area

prefrontal cortex

The prefrontal cortex is involved in voluntary motor movement:

•Using its executive functions, such as judgement and planning, it recognises when a motor movement should be initiated and plans this motor movement.

•The prefrontal cortex then sends this motor information to the premotor cortex.

premotor cortex

•The premotor cortex receives planned motor movements from the prefrontal cortex and organizes them into a sequence of motions.

•The premotor cortex then transmits this sequence to the primary motor cortex for execution.

primary motor cortex

•The primary motor cortex initiates voluntary motor movements.

•It receives the sequence of motions from the premotor cortex.

•It then signals to the cerebellum to relay this motor information to the skeletal muscles, which carry out this motor movement

broca’s area

•Broca’s area is responsible for the production of speech and language.

•It coordinates the muscle movements required to produce fluent speech, such as tongue, lip, jaw, and vocal cord movements.

•Broca’s area is ONLY located in the left frontal lobe hemisphere.

parietal lobe

•It plays a role in interpreting sensory information, perceiving 3D objects and spatial reasoning.

primary somatosensory cortex

•Touch, temperature, pressure, pain, and other sensations are received and processed by the primary somatosensory cortex.

occipital lobe

back half of the occipital lobe

•This lobe is responsible for sight/vision

primary visual cortex

•receiving and processing visual information.

temporal lobe

object recognition and memory, receiving and processing auditory information and speech comprehension.

wernike’s area and primary auditory complex

primary auditory cortex

receiving and processing auditory information.

The primary auditory cortex in the left cerebral hemisphere processes verbal sounds, such as spoken words.

wernicke’s area

comprehension and production of meaningful speech.

Wernicke’s area is only located in the left temporal lobe.

left hemisphere

organisation of language expression and comprehension

more logical and analytical tasks

right hemispheres

is involved in language comprehension to some degree, but the left hemisphere is dominant in its expression.

more creative and emotions

how hemispheres work together

when speaking, the left hemisphere controls the speech production, but the right hemisphere helps with understanding tone and context.