Brain & How We Learn

7/27/2019 Brain & How We Learn

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MINISTRY OF BASIC EDUCATION, SPORT AND CULTURE

COMPENSATORY TEACHING

FACILITATORS WORKSHOP

2001

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HOW WE LEARN:

THE ROLE OF THE CENTRAL

NERVOUS SYSTEM


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HOW WE LEARN.INTODUCTION:

We know there is an interplay between what we have inherited form our bloodline, what happens during or after birth and ourenvironment (Nature and Nurture). But, we have to know what happens with all the stimuli from the environment that bombards us,and why some of us cannot cope with it.

The brain is the centre where all stimuli is received, processed and given meaning to. Learning is a process of sensory input,

processing of information which takes place in the brain and output which is in the form of any kind of motor movement (speech,writing, performance,.

INPUT PROCESSING: OUTPUT:Eyes The Central Nervous System, Movement (e.g. speechEars production, writing,Tactile (touch) performing a task, etc.)Kinesthetic (feeling of movement)

Not nearly all of the functions of the brain have been explored, but a number of advances have been made over years. It is known thatthe brain can be roughly divided into structurally functional areas, that these areas work in an integrated fashion and that it can bedetermined by technical devices and substance injections. Usually the functional areas are numbered.

Studies include imaging of the brain to determine activity or increased blood-flow during particular tasks to show the involved areasof the brain. These scans can also indicate diseased areas like brain tumors, and structural abnormalities. The following are acronymsfor brain imaging: CT is an X-ray type of scan of brain structures and then imaged on a computer, EEG, EP & MEG graphs forelectrical brain activity of different brain structures, MRI applies a strong magnetic field to the brain to study smaller brain structuresand nuclei, PET, CBF and SPECT are all used in the imaging for region blood metabolism where activities take place.

We will try and give simple pictures and descriptions of the areas and functions of the brain, hemispheric dominance, and neuro-biochemistry.

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Hemispheres

The brain is divided into a left hemisphere and right hemisphere. These two sides are connected by the corpus callosum. (see later)

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LEFT RIGHT

C o r p u s

C a l

l o s u m

Right Brain functions

NON-VERBAL Gestalt/ Holistic images, shapes,

pictures) Sense of continuation of existence

over time (past, present, future) 3-Dimensional images / depth Colours and hues Pitch, accent, sound, melodies Non-verbal language (body-

language/ read between the lines)/ hidden communication

Left Brain functions

VERBAL Realistic Detail as in words, analysis Logical sequence/order as letters in

words, numbers, sequential facts, etc Read Speak Write Speaking


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We tend to develop our left hemisphere more that the right hemisphere due to ourexposure to language. Instead we should integrate functions of both hemispheres, e.g.use more melodies in teaching, use colours, visualise pictures in your mind, think of ourselves another time or place, try to read what people think by watching their bodylanguage and facial expressions,. That is why teachers should integrate brain functions

when teaching.

The two halves of the brain are further divided into four parts: (The right side issimilar to the left side)

The Pre-frontal Lobes

The Parietal Lobes

The Occipital Lobes

The Temporal Lobes

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Inside the brain The Cortex Process information. Decision and initiation of

concrete action Receptive language and

speech functions Storing and recalling

Eye

Pre-frontal cortex: Planning Insights

Empathy

Introspection

Intuision Decision on action

Control of

The Limbic system :

Biochemical centre.

Control pain sensation.

Emotional arousal.

Plays a role in:memory(hippocampus), instinctivebehaviour, impulse control,

perseveration, frustrationtolerance, temperature, hunger,arteries, etc

The Hind-brain: Movement Balance Muscle tone & control in

keeping the posture correct Arouse and relax muscle

groups to perform amovement.

The Brainstem Respiratory Functions Cardiovascular functions Sleep and consciousness Contain cell-bodies for

sendingneurotransmitters tohigher brain centres

Reticular Activating System(RAS) Carry ascending and

descending neurons andCranial nerves

Alertness andwakefulness

May involve motivationto do something.

Pons

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The Limbic System Parts

1. Hippocampus & Amygdala

2. Basal Ganglia

3. Thalamus

Main Functions: Memory

The right side: memory forspatial orientation/position, etc.

The left side: memory for verbalmaterial

In lesser degree in right side:memory for sentences (contentscan be visualised).

Memory for acquiring motorsequences

Involved in neurochemistry The Am dala is associated

Main Functions: Motor functions, posture,

muscle tone, normal movement If damaged (twitches, jerks,

tremors) Sequencing of movement,

smooth movements (e.g. as intalking)

Main Functions:

The General Post Office Receives, sends, selects,

integrates messages to and frombrain areas.

Is the centre of arousal Works with the somato-sensory

Hippocampus

Amygdala

Olfactory

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Pre-frontal lobe

S u p p

l e m e n

t a r y m o t o r

P r e - m o t o r c o r t e x

M o t o r c o r t e x

S o m a t o s e n s o r y c o r t e x

Parietal lobe

P r i m a r y a r e a

A s s o c

i a t i o n a r e a

Auditoryassociation

Brocasarealeft side

Wernickes area left

side

Temporal lobe

Occipital lobe

Visual cortex

Primary area

Association area

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468

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1147

4645

44

321

57

4340

4142

38

22

2137

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1918

17

6

24

33

2511

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9

8

4 57

3123

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29 30

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3 1 2

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181937

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Brodmans Cortical Areas

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Frontal Lobe Areas

Frontal Lobe problems Irritability and labile emotions, depression and flatness of affect, lack of motivation, difficulty with attention and concentration no:

10) A peculiar sense of humour Brocas aphasia (problems in motor production of speech) Memory problems and other higher cognitive functions, e.g. reflection, meta-cognition , abstract thinking, planning, programming,

judgement, verification

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46

8 64

45 44

47

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Frontal Lobe Functions

There is reciprocal connections with motor-sensory (no 4)and emotional areas.

Responsible for controlling contro-lateral movements (6)

Articulation /Speech production (no 44) and writing in thedominant hemisphere.

Eye movements (no 8) This lobes functions are critical to personality and

behaviour, abstract thinking, planning, programming,memory, judgement, verification and higher mental

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Difficulty in distal movement such as writing, speech, eye-movements, face, etc. (fine motor movements) as well as speed andstrength of movement. (no 4)

Poor body and limb movement (parietal cortex) (nos 4, 6, 8), to alter movements, or to make a series of smooth movements(nos : 5, 7).

Cannot plan movement, but know how it should be done ( no: 6) A learner has difficulty to learn through movement. No voluntary gaze (nos : 8, 9) Total inhibition or no inhibition of response (inappropriate or uninhibited behaviour) (nos: 9, 10, 11) Aphasia ( a language disorder) (no: 44). Cannot put matter into series, sequential order (no: 46). Cannot put letters or sounds into sequence to form a word, or words into

sentences, counting in correct order or tell a story in a sequence of events. Problems with orientation in space (no: 47). Cannot find his/her way from one place to another, cannot read maps, difficulty to

write between lines, turns letters and numbers upside-down . Problems with association (integrated function) Problematic social behaviour (no: 11) Does not know ethics in behaviour, hyper-active and uncontrollable, impulsive behaviour,

seen as naughty or unmannered. Poor olfactory discrimination (no: 45). Cannot learn through tasting and smelling

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The Parietal Lobe Areas

Parietal Lobe problems Problems to discriminate tactile stimuli (e.g. through touch) (nos: 1, 2, 3). Inability to attach meaning to sensory Visual and tactile impressions (agnosia) (nos: 5, 7, 37) Left side: Cannot deal with or manipulate objects intelligently (constructional apraxia) (nos 7, 40) Left side: Language and Math problems (nos: 39, 40) Short term memory problems (nos: 37, 40)

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1

5

7

404339

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Parietal Lobe Functions Receives and identifies sensory information from

tactile (touch/skin) receptors (nos: 1, 2, 3, 5, 7) Processes visual and auditory sensations and Praxes

(perception of speed and movement?) (nos: 7, 22,37, 39, 40)

Reaction to pain sensation (no: 43 ??) Awareness of and response to illness (nos 7, 40

right) Naming body parts (no:5, 7) Tone, melody, rhythm, tempo (nos: 42,22 right) Identif meanin of non-verbal sounds (nos 42, 22

22

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Problems with body image ( no: 7) Cannot name body parts, own or others gender, poor human figure drawings. Left-right confusion, (no: 7, 40) Child will have difficulty identifying left and right on his/her own body (laterality), confuse

directions, b/d/p confusion, and reads or writes in the wrong direction . Right hemisphere : Spatial problems (no 7, 40) (see frontal lobe spatial problems as well) Problem with eye-movement (nos: 7, 40) Mis-reaching objects (nos: 5, 7) In either or both hemispheres: Right-left disorientation, finger agnosia (through finger touch) , astereogosis (touching solid

objects) In dominant hemisphere: Alexia (inability to read), agraphia (inability to write), anomia (difficulty to recall the names of things),

ideomotor and kinesthetic apraxia (difficulty to execute a task or movement on command), dyscalculia (loss of ability to docalculations)

In the non-dominant hemisphere: impaired spatial abilities, denial of illness (anosognosia), inability to recognise body parts(autopagnosia), dressing oneself, constructional and kinesthetic apraxias (difficulty in completing a task or , to execute a task ormovement on command) left-side spatial neglect.

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The Occipital Areas

Occipital Lobe problems

Disturbed spatial orientation (see frontal lobe and parietal lobe problems) Visual illusions Visual hallucinations Blindness Hysteria symptoms

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181921

20

Occipital Lobe Functions Processing of visual images (no:

17) Perception, integration, imprinting

of visual information Selection, interpretation and

memory/recall of visualinformation (nos: 18, 19, 20, 21,37)

Right lobe: Perceptual organisation Left Lobe: Visual language

reception Naming, using, recognition of

objects no: 18, 19, 20, 19 left &corpus callosum)

Recognising drawn objects (nos:18, 19, 20, 21 right)

Face recognition (nos:18, 19 right)

Associate colour with objects (nos:18, 19 right)

Naming colours (nos: speech areas+ 18, 19, 37)

Recognising hues (Nos: 18, 19,

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37

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The Temporal Lobe Areas

Temporal Lobe Problems

Memory impairment (bilateral) (no 21) Left side: Language comprehension (no.: 22) Control of sexual and aggressive drives (Limbic system) Wernickes aphasia (dominant hemisphere) when speech is fluent and spontaneous, but incoherent and non-sensical Klver-Bucy syndrome (placidity, apathy, hyper sexuality, visual &auditor agnosia, amnesia, aphasia, dementia, seizures) Aprosody (non-dominant hemisphere)( cannot inflect own speech with affect or comprehend inflections of other speech)

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Temporal Lobe Functions Hearing, sound discrimination, language skills (no:

41). Selection of auditory input, e.g. organising verbal

information into categories (no: 38) Differentiation of sound sequences, pitch and

rhythm (Left lobe: Wernickes area forinterpretation, speech comprehension and memory.

Right lobe: non-verbal perception, e.g. melodies)(nos: 22, 42)

Long term memory (especially hippocampus) (no:21 - see Occipital lobe)

Sexual and aggressive behaviour Left side: Comprehension of Language (no: 22) Interpretation of gustatory and olfactory sensations Major component of limbic system

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21

Wernickes area

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Integrated Functions of the Temporal, Occipital and Parietal lobes

Translation of information Memorising Comprehension, association and expression Organisation of complex, simultaneous responses, e.g. essay writing which involves strings of thoughts, language, encoding into

equivalent graphemes, recall of the letter symbols, verify correct spelling and syntax, transferring these into kinesthetic patterns activation of different nerves and muscle groups and motor movement (writing)

Internal spatial organisation according to body-in-space awareness and spatial orientation according to input from auditory, visualand tactile-kinesthetic modalities.

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Example of areas that function for Language

Hear and comprehend word:

Spoken word Areas 41, 42 Wernicke (area 22)

Speak

Cognition Wernicke Broca Face Cranial nerves

Read

41

4252

22Wernickes area

44Brocas area

4

321

39 F a c e

19 18

17

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Written word Area Areas 18, 19 Area 39 Wernicke

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Major structures involved in Reading and Spelling

Left hemisphere only Phonetic reading and spelling

Right hemisphere only Grapheme reading and spelling

Broca left & Wernicke right Phonetic spelling - grapheme reading

Wernicke - left & Broca right Phonetic reading grapheme spelling

Weak left or right Broca Poor phonetic or grapheme spelling

Weak left or right Wernicke Poor phonetic or grapheme reading

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Hemispheric dominance

The two hemispheres are connected by the corpus callosum. The dominant hemisphere isthe hemisphere that is organised to express language. The left hemisphere is regarded asthe dominant one in 97% of the population, including 99% of right-handed persons and60 70% of left-handed persons. Language dominance is therefore not completelysimilar to hand dominance. There are also cases of mixed dominance for language, as inthe case of hand-dominance.

Normally, in a right-handed person the left hemisphere is dominant and the motorpathways cross through the corpus callossum.

Hand-dominance and WritingLeft-handed person Right-handed person

LEFT RIGHT

C o r p u s

C a l l o s u m

motor area

somato-sensory area


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Hearing

Lift up yourhand

LEFTRIGHT

C o r p

u s

C a l

l o s u m

LEFT RIGHT

C o r p u s

C a l

l o s u m

4, 6 4, 6

22, 39, 40 22, 9, 40

Hearing and Performing an action: Damage to pathways

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Smelling and identifying: Damage to pathways

Vision

Vision also has a crossed system, therefore there may be eye-dominance too.

LEFT

RIGHT

LEFT RIGHT

C o r p u s

C a l

l o s u m

22, 39, 4022, 39, 40

rose

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The right sides of the eyes will see one part of an image and send messages to the right,back side of the brain. The left side will see the other part and send messages to the left,back side of the brain

Vision, and damage to pathways

LEFT

RIGHT

man

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Brain Biochemistry

Brain biochemistry refers to substances in the brain that transmits messages (impulses) toareas of the brain . The substances are called neuro-transmitters or neuro-messengers

Chemical neurotransmission:Without going into detailed descriptions and intricate processes, nerve impulses areconverted into a chemical signal in the pre-synaptic neuron. This is a release of neurotransmitters by the pre-synaptic neuron and the detection of this transmitter byreceptor proteins. At the synapse where two neurons meet, messages are carried over acleft to enter the next neuron through receptors.

Receptors are proteins in the pre-synaptic or post-synaptic neuronal membrane, andspecifically recognise neurotransmitters.

There are basically three types of neurotransmitters that can be found in a single neuron: monoamines ( dopamine, norepinephrine, epinephrine, serotonine, acetylcholine,

histamine) amino acids peptides

Alterations in the amounts of released neurotransmitters can influence learning,behaviour or other conditions.

Dopamine imbalances are linked to schizophrenia, Parkinsons disease Manic-depressive mood disorders.

An imbalance in Norepinephrine has been linked to depression . An imbalance in Serotonin has been linked to mood disorders, anxiety disorders

(including obsessive-compulsive disorders), violence and schizophrenia Acitylcholine has been linked to movement disorders (Parkinsons disease,

Huntingtons chores and Tardive dyskinesia) as well as mood and sleep disorders,depression.

Histamine has been linked to allergic reactions, sedation, weight gain, hypotension. Certain Amino-acids have been linked to anxiety, epilepsy, Huntingtons chorea,

Parkinsons disease. Different Peptides have been linked to regulation of pain, mood, eating an movement

disorders,

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Neuro- endocrinology

Hormonal messages are carried from the hypothalamus to the pituitary gland whereadditional hormones are secreted, e.g. cortisol (or blocked) and so on.The hormone vasopressin is involved with blood-pressure, fluid and electrolyte balance.It can be stimulated by pain, stress and certain drugs and is inhibited by alcohol.Endocrine disorders can be seen in some psychiatric patients, e.g. Cushings syndrome,depression and suicide attempts, hypomania, emotional lability, , disturbance of thegrowth hormone.

Pons

Dopaminergic pathways:

Noradrenergic pathways:

Serotenergic pathways:

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Psycho-immunology The immune system reciprocally interacts with the nervous and endocrine systems.Damage to parts of the limbic system and the pituitary gland can result in dysfunction inthe immune system.

It is thought that either an infection may influence the immune response negatively orthat an abnormal immune system allows the infection to develop.

Symptoms may include depression, insomnia, emotional lability, nervousness, andconfusion. T-cell prolifiration was found to proliferate in bereaved persons. Stress,loneliness and poor coping skills is another cause

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Brain & How We Learn