Psychology 🧠 (Week 2)

• The central nervous system (CNS) controls most functions of the body and mind
• Consists of two parts: the brain and the spinal cord
• The brain is the centre of our thoughts, the interpreter of our external environment, and the origin of control over body movement
• Interprets information from eyes (sight), ears (sound), nose (smell), tongue (taste), and skin (touch), as well as from internal organs such as the stomach
• Not all brains, and certainly not all parts of a brain are equal
• The type of brain and function a brain devotes space and energy to is dependent on an organism’s environment
• Three areas of the brain:

  • Old/hind brain (reptilian)
  • Middle brain (limbic system)
  • New brain (complex cognitive function)
• The brain is the centre of our thoughts, the interpreter of our external environment, and the origin of control over body movement
• The brain interprets information from our eyes (sight), ears (sound), nose (smell), tongue (taste), and skin (touch), as well as from internal organs such as the stomach
• Not all brains, and certainly not all parts of a brain are equal
• The type of brain and function a brain devotes space and energy to is dependent on an organism’s environment
• There are three areas of the brain:

  • Old/hind brain (reptilian)
  • Middle brain (limbic system)
  • New brain (complex cognitive function)
• The brainstem is the oldest part of the brain, beginning where the spinal cord enters the skull
• The brainstem is responsible for automatic survival functions
• Medulla:

  • Responsible for life-maintaining processes such as breathing and heartbeat
  • Triggers vomiting and sneezing
• Pons:

  • Major highway that connects the spinal cord to the brain
  • Involved in automatic processes, especially the sleep-wake cycle
• Reticular Formation:

  • Controls arousal and consciousness (sleep-wake cycle)
  • Damage can cause a coma
• Thalamus:

  • Sits on top of the brain stem
  • Receives incoming sensory information and sends it to the cortex for processing
• Cerebellum:

  • Responsible for fine motor control, coordination, posture, and balance
  • Helps with learning and remembering physical skills
  • Affected by alcohol, causing problems with coordination, balance, and walking
• Limbic System:

  • Involved in processing emotion and long-term memory
• Amygdala:

  • Involved in processing and triggering emotion, especially fright, fear, and aggression
  • Alerts you in dangerous situations
  • Triggers freeze, fight-or-flight response
  • Damage can cause loss of fear, aggression, or passivity
  • Releases stress hormones
  • More emotional response leads to less conscious thought guiding behavior
• Fun facts about Amygdala:

  • Helps read other people's emotions
  • Stores memories from highly emotional situations
  • Connects emotions with experiences, influencing future behavior
  • Responsible for emotional learning and memory construction
• Hippocampus:

  • Helps store information into long-term memory
  • Stores spatial memory
  • One of the first brain regions affected by Alzheimer's Disease
• Hypothalamus:

  • Regulates autonomic nervous systems
  • Monitors and regulates body temperature, hunger, thirst, and sexual responses
  • Lateral Hypothalamus regulates hunger
  • Ventromedial Hypothalamus regulates feelings of fullness
• Cerebral Cortex:

  • Wrinkled outer portion of the brain
  • Contains left and right hemispheres with 4 lobes: Frontal, Parietal, Temporal, Occipital
• Frontal Lobes - Prefrontal cortex:

  • Responsible for executive functions like judgement, planning, reasoning, problem-solving
  • Helps with moral judgement
  • Damage can lead to loss of moral compass, violence, or offensiveness
• Frontal Lobes - Motor cortex:

  • Controls voluntary movement
  • Body areas requiring precise control occupy more cortical space
• Left Frontal Lobe - Broca's Area:

  • Involved in speech production
  • Broca's Aphasia causes difficulty in producing speech
• Temporal Lobes:

  • Involved in hearing, language processing, and memory
  • Connected to the limbic system
  • Involved in long-term memory storage
• Temporal Lobes - Primary Auditory Cortex:

  • Main site of auditory perception and processing
  • Wernicke's Area involved in comprehension and understanding of language
  • Wernicke's Aphasia causes difficulty in expressing and understanding language
• Temporal Lobes - Right Fusiform Gyrus:

  • Allows recognition of human faces
  • Prosopagnosia causes impairment in recognizing faces
• Parietal Lobes:

  • Process sensory signals from the body
  • Help with spatial orientation
• Parietal Lobes – Somatosensory Cortex:

  • Registers and processes body touch and movement sensations
  • Sits directly behind the motor cortex
• Occipital Lobes:

  • Processes visual information from the eyes
  • Contains neurons specialised to recognise lines, angles, shapes, and movement
  • Damage can cause blindness or disruption to vision
• Cortex lateralisation:

  • Split brains and left and right hemispheres
• Corpus Callosum:

  • Large band of neural fibres that connect the left and right hemispheres
  • Allows both hemispheres to communicate with each other
  • Severing the corpus callosum disconnects the hemispheres and is used to treat severe, uncontrolled epilepsy
• Brain lateralisation:

  • Some neural functions or cognitive processes are specialised in one hemisphere
  • Right side of the brain controls the left side of the body
  • Left side of the brain controls the right side of the body
• Lateralised functions:

  Right Hemisphere:

  • Sensory processing from left side of the body
  • Motor control of the left side of the body
  • Spatial ability
  • Modulating speech
  • Recognising faces, places, and objects
  • Perceiving and expressing emotion

  Left Hemisphere:

  • Sensory processing from right side of the body
  • Motor control of the right side of the body
  • Speech, language, and comprehension
  • Maths calculations
  • Time and sequencing
  • Recognition of words, letters, numbers
• Brain function round-up
• Spinal cord function:

  • The spinal cord is the highway for communication between the body and the brain
  • When the spinal cord is injured, the exchange of information between the brain and other parts of the body is disrupted