The Brain and Neuropsychology

Frontal lobes: location

Located just behind the forehead, at the front of the brain

Frontal lobes: Function

• Decision making

• Problem solving

• Concentration

Symptoms of Frontal Lobe Damage

• Changes in social behaviour, mood and personality

• Weakness of loss of movement in areas of the body (paralysis)

Temporal lobe: location

Located on the side of the head above the ears

Temporal lobe: function

• Hearing and understanding sounds

• Understanding and creating speech

Symptoms of Temporal Lobe Damage

• Difficulty in learning and remembering new information

• Difficulty in understanding spoken words

Parietal lobes: location

Near the back and top of the head

Parietal lobes: function

• Sense of touch

• Spatial orientation

Symptoms of Parietal Lobe Damage (left side)

• Confusion between right and left of the body

• Difficulty with writing, reading and mathematics

Symptoms of Parietal Lobe Damage (right side)

• Problems with self-care skills

• Weakened ability to analyse pictures

Symptoms of Parietal Lobe Damage (both sides)

• Problems with visual attention and motor skills

• Inability to control your gaze

Occipital lobe: location

The back of the brain

Occipital lobe: function

• Visual perception

• Distance and depth perception

Symptoms of Occipital Lobe Damage

• Difficulty in identifying colours

• Problems with vision

Cerebellum: location

At the back of the head, above and behind where the spinal cord connects to the brain

Cerebellum: function

• Muscle and balance control

• Relays information between body muscles

Symptoms of Cerebellum Damage

• Loos of coordination of motor skills (asynergia)

• Slurred speech (dysphonia)

Muscle tone

The tension/resistance to movement in muscles, helps us to hold our bodies upright when we are sitting and standing, includes the control, speed and amount of movement we can achieve

Cerebrum

The largest part of the brain which contains all the lobes

Cerebrum: function

• Initiates and coordinates movement

• Regulates temperature

Lateralisation of function

Each hemisphere of the brain has different functions, some behaviours are controlled more from the left than the right, vise versa

Asymmetrical functions

Both hemispheres are not exactly the same, their structure and their functions vary which makes them asymmetrical despite looking similar (not mirror images), each hemisphere controls the opposite side of the body

Corpus Callosum

A thick layer of nerve fibres which connects the brain functions for the two hemispheres to communicate and work together

Absence of the Corpus Callosum

Happens at birth and mostly diagnosed in the first two years of life, the disorder can be without apparent symptoms in milder cases

Absence of the Corpus Callosum: possible symptoms

• Vision problems

• Low muscle tone (hypotonia)

• Unusual head shape and facial features

• Brain abnormalities

Hydrocephalus

A brain abnormality where there is excess fluid in the brain which puts harmful pressure on the brain’s tissues

Right Hemisphere

R for recognition

• Spatial awareness

• Ability to recognise and perceive faces

• Creativity

• Processing music heard

Left hemisphere

L for language

• Processing language

• Contains the Broca’s Area

• Ability to write and understand language

Broca’s Area

Controls production of speech, linked to the control of nerve cells in the face that allow us to speak and process language, located in the frontal lobe

Sex differences

It was always assumed that females were better at language (the left) and males were better at spatial skills (the right)

Sex differences: evidence

Strengths of lateralisation explaining sex differences

• There is evidence from a study by Harasty et al. (1997) 

• Study by Rilea et al. (2005)

• Lots of reliable and scientific evidence available

Weaknesses of lateralisation explaining sex differences

• Some research by Rilea et al. are weak

• Study by Sommer et al. (2004) which suggested no strong evidence

Damasio et al. (1994) Phineas Gage

After a metal pipe pierced through Gage’s skull, Damasio et al. used a 3D model to find out which parts of his brain was damaged for his personality to change drastically

Damage to Phineas Gage’s brain

• Damage to both hemispheres of only the frontal lobe

• Damage to his ventromedial area of the frontal lobes caused him to be impulsive

Hippocampus

Responsible for memory and learning, holds short-term memories and transfers them to long-term storage

Alzheimer’s disease

A progressive disease where dementia symptoms gradually intensify, starting from mild memory loss to possible loss of ability to respond to conversations and environments. This happens to patients with a loss of volume in the hippo campus, the more tissues lost, the worse the disease gets.

Neurons

Cells in the nervous system that help with communication within the body, they send electrical and chemical messages to connect organs and glands, they can relation information back into the central nervous system

Neuron composition

Cellbody with nucleus, dendrites, axon, myelin sheath, terminal knobs

Dendrites

Carry electrical charges from one neuron to the next

Axon

Carries the charge down the neuron and connects the cell body of a neuron to the terminal button, protected by a fatty myelin sheath

Terminal button

End of a neuron

Neurotransmitters

Chemicals that are released during neurotransmission when a nerve impulse reaches the end of a nerve fibre, passes messages from one neuron to another

Electrical impulse order

Dendrites

Cell body

Axon

Terminal branches

Synaptic vesicles

Synaptic gap

Receptor site

Central Nervous System (CNS)

Helps the brain and body communicate by passing messages back and forth between them. Sensory nerves in the body send messages to the brain through the spinal cord and vise versa

Peripheral Nervous System (PNS)

The spinal cord can activate this system and makes the body do actions the brain is telling it to do. Information is passed around in a fraction of a second.

Synapse

A gap between two neurons that allows messages (in the form of neurotransmitters) to pass from one cell to another

Visual agnosia

Information sent from the eyes to the brain cannot be understood, so the person cannot identify the things they can see. The person can still see the object perfectly well but cannot make sense of this information

Visual agnosia example

Unable to recognise the colour of an object, objects and name them or places they are familiar with

Prosopagnosia (face-blindness)

Unable to recognise faces even though they can be seen, the brain is unable to recognise who the face belongs to even if they know the person very well. All faces they see look the same and cannot tell them apart.

Cause of Prosopagnosia

Damage to a part of the brain (called the fusiform face area (FFA)) near the back of the temporal lobe, next to the occipital lobe