PSYC2260 - Midterm 1

• • Brain hack #1 is to breathe, mindfulness buffers stress which is the number one neuroplasticity inhibitor
  • Brain hack #2 is to move
  • Brain hack #3 is to learn
• Cogito ergo sum (i think therefore I am) - rene descartes 

  • Methodological skepticism: cogito ergo sum 
  • Interactive dualism
  • Both mind (or soul) and body exist and causally interact to produce conscious experience
• Cognition is the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses
• cognition refers to the mental processes, such as perception, attention, and memory that are what the mind creates
• • Donders measured how long it takes a person to make a decision 
  • Reaction time (RT) experiment 

  → measures interval between stimulus presentation and persons response to stimulus 

  → simple RT task: participant pushes a button quickly after a light appears 

  → choice RT task: participant pushes one button if light is on right side, another if light is on left side  

  → choice RT - simple RT = time to make a decision 

  ~ choice RT =1/10th sec longer than simple RT 

  ~ 1/10th second to make decision 

  ~ mental responses cannot be measures directly but can be inferred from the participants behaviour
• Wundt: structuralism 

  • Established the first scientific psych lab 
  • Developed approach called structuralism:

  → overall experience is determined by combining basic elements of experience called sensations 

  • Used method of analytic introspection: 

  → participants trained to describe experiences and thought processes in response to stimuli
• Ebbinghaus: memory and forgetting

  • Read list of nonsense syllables aloud to determine number of repetitions necessary to repeat list without errors 
  • After taking a break, he relearned the list 

  → short break intervals= fewer repetitions necessary to relearn list 

  → learned many different lists at many different retention intervals 

  • Savings = (original time to learn list) - (time to relearn list after delay)
  • Savings curve shows savings as a function of retention interval 
• William james’s principle of psychology 

  • Observations based on the functions of his own mind, not experiments 
  • Considered many topics in cognition, including thinking, consciousness, attention, memory, perception, imagination, and reasoning
• Watson and behaviourism 

  • Watson noted two problems with analytic introspection method: 

  → extremely variable results per person 

  → results difficult to verify due to focus on invisible inner mental processes 

  • Proposed a new approach called behaviourism

  → eliminate the mind as a topic of study 

  → instead, study directly observable behaviour
• Watson's little albert experiment 

  • 9 month old frightened by a rat after a loud noise was paired with every presentation of the rat
  • Examined how pairing one stimulus with  another affected behaviour 
  • Demonstrated that behaviour can be analyzed without any reference to the mind
• Skinner: conditioning and behaviourism 

  • B.F skinner interested in determining the relationship between stimuli and response  
  • Operant conditioning

  → shape behaviour by rewards or punishments 

  → rewarded behaviour more likely to be repeated 

  → punished behaviours are less likely to be repeated 

  • Behaviourism approach was dominant from the 1940s through the 1960s
• • Tolman trained rats to find food in a four armed maze 
  • When a rat was placed in a different arm of the maze, it went to the specific arm where it previously found food 
  • Tolman believed the rat had created a cognitive map, a representation of the maze in its mind 

  → the map helped the rat navigate to a specific arm despite starting the maze from a different spot 

  → rejected the behaviourist perspective for the rats actions
• • Skinner - verbal behaviour 

  → argued children learn language through operant conditioning

  ~ children imitate speech they hear 

  ~ correct speech is rewarded 

  • Chomsky 

  → argued that children do not only learn language through imitation and reinforcement 

  • Children say things they have never heard and cannot be imitating 
  • Children say things that are incorrect and have not been rewarded for 

  → language must be determined by inborn biological program
• • information processing approach

  → way to study the mind based on insights associated with the digital computer - press a button that matches the one on a screen and time how long it takes person to press the correct button

  → states that operation of the mind occurs in stages
• Attention and flow diagrams 

  • Cherry built on james idea of attention 

  → present message A in left ear and message B in right ear 

  → subjects could understand details of message A despite also hearing message B 

  • Broadbent developed flow diagram to show what occurs as a person directs attention to one stimulus 

  → unattended info does not pass through the filter
• Artificial intelligence and info theory 

  • artificial intelligence

  → making a machine behave in ways that would be called intelligent if a human were so behaving 

  → newell and simon created the logic theorist program that could create proofs of mathematical theorems involving logic principles

  • Turing test: if a person can distinguish between texting with a person or AI
• Memory: a higher mental process

  • Atkinson and shiffrin developed a three stage model of memory 

  → sensory memory (less than 1 second)

  → short term memory (a few seconds, limited capacity)

  → long term memory (long duration, high capacity)

  • Info we remember is brought from long term memory into short term memory 
  • Tulving divided long term memory into 3 component 

  → episodic - life events 

  → semantic - facts 

  → procedural - physical actions 
• The physiology of cognition 

  • Neuropsych studies behaviour of people with brain damage
  • Electrophysiology studies electrical responses of the nervous system including brain neurons 
  • Brain imaging

  → positron emission tomography (PET)

  → functional magnetic resonance imaging (fMRI)

  → both technologies show which brain areas are active during specific episodes of cognition
• Cognitive Neuroscience

  • Cognitive neuroscience is the study of physiological basis of cognition, and involves an understanding of both the nervous system and the individual units that comprise that system
• Nerve Nets and The Neuron Doctrine

  • Early concept of interconnected neurons creating a nerve net, and was contradicted by the neuron doctrine - by Ramon y Cajal, studied Golgi staining, said that individual nerve cells transmit signals and are not continuously linked with other cells
  • We have an average of 86 billion neurons
• Building Blocks of the Nervous System

  • Neurons are cells that are specialized to create, receive, and transmit information in the nervous system, and each neuron has a cell body, axon, and dendrites
  • The cell body contains mechanisms to keep the cell alive (the nucleus), dendrites are multiple branches reaching from the cell body which receive information from other neurons, and an axon is a tube filled with fluid that transmits electrical signals to other neurons
  • Glial cells are important in waste removal
  • Blood cells and haploid cells have no DNA
• How Neurons Communicate

  1. Neurons receive a signal from the environment

  2. Information travels down the axon of the neuron

  3. Information travels to the dendrites of another neuron
• Microelectrodes


  Pick up electrical signals, placed near axons
• The size of action potentials is not measured; it remains consistent, the rate of firing is measured (Rate Coding)
• Low-intensity stimulus

  Slow firing
• High-intensity stimulus

  Fast firing
• Synapse


  The space between the axon of one neuron and the dendrite or cell body of another
• Neurotransmitter release

  1. Action potential reaches the end of the axon

  2. Synaptic vesicles open

  3. Chemical neurotransmitters are released

  4. Neurotransmitters cross the synapse

  5. Neurotransmitters bind with the receiving dendrites
• Resting state of an action potential


  • -70 mV
• Threshold of an action potential

  • -55 mV
• Neurotransmitters

  • Acetylcholine (muscles)
  • Dopamine (reward pathway)
  • Epinephrine (nerves)
  • GABA (inhibitory)
  • Serotonin (mood regulator)
• • The principle of neural representation is that everything a person experiences is based on representations in the person's nervous system
• Feature Detectors


  Neurons that respond best to a specific stimulus
• Hubel & Wiesel's research

  • Conducted with visual stimuli in cats
  • Edge of the slide with the dot on it made the neuron in the cat fire
• Experience-dependent plasticity


  How the structure of the brain changes with experience
• Kittens exposed to vertical-only stimuli over time could only perceive verticals in normal stimuli, demonstrating that perception is determined by neurons that fire to specific qualities of a stimulus
• Lines of different orientations are important because survival is all about edges and moving edges (object perception)
• Hierarchical Processing

  • When we perceive different objects, we do so in a specific order that moves from lower to higher areas of the brain, and this ascension corresponds to perceiving objects that range from lower (simple) to higher levels of complexity
  • Bottom of brain (ventral) is "what" pathway, Top of brain (dorsal) is "where" pathway
• Specificity coding


  Representation of a stimulus by the firing of specifically turned neurons specialized to respond only to a specific stimulus
• Grandmother cell theory


  Another name for specificity coding