What is Cognitive Psychology? Flashcards
What did Professor John R Anderson define cognitive psychology as?
Cognitive psychology is the science of
how the mind is organised to produce
intelligent thought and how it is realized
in the brain
What did Wundt study and what was wrong with his methods?
Psychology the study of conscious experience.
- Using introspective methods
- Introspective reports of conscious experiences dealt with the unobservable and private, and they were unreliable.
What did Watson study?
Psychology is the study of behaviour. (Behaviorism)
What did followers of behaviourism believe?
Behaviourists denied the existence of the “mind”
- Responses (behaviour) is determined by environmental events (stimuli) and reinforcement arising from historical responses to them.
- Internal mental activity does not exist. People do not have strategies, memories, beliefs etc, not even mental arithmetic.
What did Smith et al (1947) prove about the theory of behaviorism?
Smith voluntarily fully paralyzed himself (hence no muscle responses) and was kept alive via an artificial respirator. HOWEVER CONTRARY to behaviorism, he was able to understand speech & what was going on, and he remembered it.
What was the 3 flaws which lead to behaviorism being overthrown?
- Behaviourist principles proved incapable
of explaining performance on WWII tasks
e.g. radar, bomb aiming, code breaking. - CHOMSKY (a famous linguist): Showed that logically
Behaviourism is incapable of accounting
for natural language acquisition (infants and toddlers). - The powerful metaphor of mind provided
by computers and artificial intelligence.
- computers being able to replicate human thought processes
- e.g. – Newell and Simon produced a program
capable of proving theorems in formal
logic and it appeared to mimic humans
at least to some extent.
What was a legacy left behind by Behaviorism?
Very good and controlled set of methods for experimental study of observable behavior
What is information processing models?
Information processing models resemble processing in
computers – made Cognitive Psychology popular and
contributed to the decline of Behaviourism
How is information processed in information processing?
- Information made available by the environment is processed by a series of processing systems.
- Processing system is a set of processes that work together to accomplish a type of task, using and producing representations as appropriate.
- The major goal of research is to specify these processes and representations.
How is an information processing task analysed?
Information-processing analysis breaks a cognitive task into a set of abstract information-processing steps.
e. g. shown 3 numbers (7, 8, 9) then asked whether a certain number was present (9).
- -> 9 = 3?, 9 = 9?, 9 = 5?, –> decide –> generate response –> YES
What is cognitive neuroscience?
Cognitive neuroscience is the study of how cognition is realized in the brain.
What did brain imaging help resolve?
Brain imaging a new tool to help resolve issues between competing information-processing theories
Where does information processing mainly occur?
information-processing occurs mainly in neurons that
reside in the brain and especially the cortex – which is small or non existent in many species.
What is a neuron?
A special kind of cell that accumulates and then
transmits electrical activity.
- There are ≈100 billion neurons in the human brain –
100,000,000,000 and on average each connects to 1000 other neurons. A very complex network.
What is the ratio of neurons compared to other cells in the brain? and what is important about glial cells?
Neurons are out numbered 9:1 in the brain by other cells, including glial cells. Recent discoveries suggest glial cells may facilitate the permanent synaptic changes that underlie learning. (Einstein apparently had an unusually high proportion of glial cells.)
How do neurons communicate?
Neurons communicate by forming a synapse, neurotransmitters are released from the bouton on the terminal of a neuron, these neurotransmitters then bind to the receptors on the dendrites of the receiving neuron, changing electrical polarity of the receiving membrane.
What are the components of a neuron?
Dendrites, Cell body, axon hilock, myelin sheath, axon,, axon terminal, boutons.
Approximately how many other neurons does a neuron form synapses with?
1000 on each end (terminal and dendrites)
What is the average polarity change caused by an action potential?
polarity change from -70 mv to + 40 mv and back again within 1 ms
In expanded time, what does each action potential appear as?
A spike that travels down axons at speeds of 0.5 m/s to 130 m/s (faster in axons that are more myelinated).
Once a ____ level is reached the rate of firing of a neuron is a ___ ___ of _____ _____
threshold, continuous function, input strength
What can a neurotransmitter that fires do to the receiving neuron and how is a overall decision made by the receiving neuron?
It can either inhibit or excite the receiving neuron.
Neurons “compute” the sum of all excitatory (increase rate of firing of neuron) and inhibitory (decrease rate of firing) inputs on their dendrites.
How are excitatory connections brought about?
by decreasing a potential difference across cell boundary
How are inhibitory connections brought about?
increases the potential difference across cell boundary
When is an action potential carried down a neuron?
When the sum of all the many positive potentials minus all the negative potentials arriving at its dendrites exceeds a threshold level
Approximately how long does it take for communication to pass from one neuron, down the axon, across a synapse and to the next
neuron?
Around 10 ms (1 < 10 < 100)
How is the way information is represented different when comparing the brain to a computer?
- Computers represent information discretely in terms of patterns of 0’s and 1’s (Binary)
- Brains represent information in terms of rate of firing (>100 impulses per second), a continuously varying quantity
- Greater the rate of firing (activation) in an axon the greater its influence on “downstream” neurons.
Information-processing and hence thinking is…:
the result of the
spread of activation through the excitatory and inhibitory
synaptic connections in a vastly complex network
What are patterns of activation in neurons classified as and what can they not do?
Patterns of activation in neurons are transitory.
Transitory patterns of activation cannot encode permanent knowledge.
Do grandmother cells exist and if not, how is information represented in the brain?
No, information is represented by patterns of activation across sets of interconnected neurons (distributed representation).
What are feature detectors?
Cells that respond maximally to particular kinds of information but not to other features e.g. the red, green, blue receptors in the eye, the straight line and
angle detectors in the primary visual cortex
What are the main 3 planes the brain is viewed from?
Sagittal, Coronal and Horizontal sections
What region of the brain is of greatest interest to psychologists and why?
The cortex, as it performs most of the operations that give rise to our intelligence.
What are the lobes of each hemisphere of the cortex called?
The Frontal, parietal, occipital and temporal lobes
what is grey matter and white matter?
grey matter is a thin layer of folded cortex.
white matter are connecting myelinated axons.
what is topographic organisation?
Adjacent cells in the cortex tend to process sensory stimuli from adjacent
areas of the body
How does FMRI work?
When there is high neuron firing in the brain, there is more oxygenated blood present. Radio waves are passed through the brain the iron in the
haemoglobin produces a local magnetic field that is detected by magnetic sensors round the head.
Signal is stronger in more active areas.
What are the downsides to FMRI?
Expensive, noisy, claustrophobic testing conditions.
What is Diffusion tensor imaging (DTI)?
a variation of MRI, tracks the
movement of water molecules along nerve cell connections revealing the brain’s pathways
what are techniques like ERP, fMRI, and TMS allowing
researchers to study?
the neural basis of human cognition
with a precision - in animals
