Chapter 2 Flashcards
Theory
- Explanation for a set of observations
- Systematic body of ideas about a particular topic
- Predicts future observations
Hypothesis
- Prediction derived from a theory
- Prediction regarding outcome of a study
- Involves at least two variables
Falsifiability criterion
Predictions that can be disconfirmed by data
Can never prove a theory true
but it can be proven false
Theory that cannot be falsified
cannot be considered scientific
Induction
- Specific examples to general statements
- Observation to theory
Deduction
- General statements to specific examples
- Theory to hypothesis
STM capacity as number of items (Miller, 1956)
~7 items in STM
STM capacity as length of time (Baddeley et. al, 1975)
~2 seconds of information in STM
Naturalistic observation (Goal: Description)
Process of observing and describing a phenomenon
Correlation (Goal: Prediction)
Mathematical technique that seeks patterns in data
Experimental method (Goal: Explanation)
Means for systematically testing hypotheses in controlled situations
Model
Simplified version of phenomenon under study (ex. graph, set of equations, computer program)
Model and theory
Good model lends plausibility to theory
Only data can support or falsify a theory
Construct
Label given to set of observations that seem to be related
Memory, attention, intelligence, personality, language
Operational definition
Defines construct in terms of how it is measured
(Intelligence -> score on test)
(Short-term memory capacity-> digit span)
Validity
Degree to which instrument measures what it is clamed to measure
Reliability
Degree to which instrument gives consistent measurements for recurring thing
Experiment
- Tightly controlled situation designed to test a hypothesis
- Comparison between two groups that are treated differently
Bransford and Johnson (1972)
Hypothesis: Context aids ambiguous story comprehension
Method: Group A sees picture, hears story; Group B hears story, no picture
Experimental condition
Group that is given treatment to test hypothesis
Control condition
Group that is not given treatment to provide baseline for comparison
Independent variable
Various types of treatment given to different groups in experiment
Dependent variable
Measurement of response each participant makes to the treatment
Between-subjects design
Assigns each participant to only one condition
Within-subjects design
Assigns each participant to every condition
Hypothesis testing
- Hypothesis predicts a difference between groups
- Test hypothesis by comparing group means
Experimentation process
- Formulate hypothesis
- Design procedure
- Analyze data
- Interpret results
Latency (Reaction time)
Difference in time between presentation of stimulus and initiation of response
Accuracy
Percentage of correct responses
Error rate
Percentage of incorrect responses
Nonword
Pronounceable letter string that is not a word in English
Lexical decision task
Participant sees a string of letters, decided ASAP if it is a word
Priming
- Implicit memory process
- Recall enhanced due to previous exposure
Immediate recall (STM)
NO TIME LAPSE between stimulus and response
Delayed recall (LTM)
TIME LAPSE OF SEVERAL MINUTES OR MORE between stimulus and response
Free recall
Repeat items in ANY ORDER
Serial recall
Repeat items in EXACT ORDER
Primacy and recency effects
- FIRST and LAST items BEST RECALLED
- MIDDLE items LEAST RECALLED
Implicit learning
Outside of conscious awareness
Saccade
Quick movement of eyes while reading
Fixation
Momentary gaze of eyes on single location
Regression
Movement of eyes back to previously viewed location
Brainstem (medulla, pons)
Interior portion of brain, regulates body functions
Cerebellum
Behind brainstem, coordinates movement
Corpus callosum
Band of axons that connect left and right hemispheres
Cerebral cortex
Outer covering of forebrain, mental functions giving rise to consciousness
Frontal lobe
Front of head, motor movement, planning and decision making
Parietal lobeq
Top of head, monitors body position, navigation through space
Occipital lobe
Back of head, processes visual input
Temporal lobe
Side of head, processes auditory input, object recognition
Lateralization
- Some cognitive functions processes mainly in one hemisphere
- Traditional language areas in left hemisphere
Broca’s area
Left frontal lobe, speech production
Broca’s aphasia
Halting, effortful speech, good comprehension
Wernicke’s area
Left temporal lobe, speech perception
Wernicke’s aphasia
“Word salad” speech production, poor comprehension
Subcortical structires
Structures below cerebral cortex
Hippocampus
Temporal lobe, memory and learning
Amygdala
Temporal lobe, emotion and memory
Basal ganglia
Base of forebrain, procedural learning and routine actions
Electroencephalography (EEG)
Records voltage fluctuations at scalp
Event-related potential (ERP)
Waveform extracted from EEG, signifies cognitive process
Components
A specific ERP waveform that is tied to a particular cognitive process
N400
Component signaling semantic anomaly
Positron Emission Tomography (PET)
Track mildly radioactive substance injected into the bloodstream
Functional Magnetic Resonance Imaging (fMRI)
Uses magnetic properties to track blood flow
