Approaches + Methods Flashcards
What is the purpose of Tinbergen’s four questions ?
to cause the researcher to think about in-depth causes of behaviour + take a logical comprehensive approach.
Initially for animals can also be applied to humans.
What is the first of Tinbergen’s 4 questions?
- Physiological mechanism (causation) - How does it work?
How does a certain behaviour relate to activity in the brain.
Roles of neurotransmitters and hormones on stimulating behaviour.
What is the second of Tinbergen’s 4 questions
- Ontogenetic mechanism (developmental) - How does it develop over the life of the individual animal?
Considers influence of both genes (nature) and environment (nurture)
What is the third of Tinbergen’s 4 questions
- Evolutional mechanism (phylogeny) - Why did the behaviour develop in the history of the species?
Are there similar traits the animal shares with ancestors?
What is the fourth of Tinbergen’s 4 questions
Functional mechanisms (adaptation) - What is it for? / Why is it done now?
Function refers to traits that solve a survival problem in the current environment.
What is the aim of neuroscience?
to understand the relationship between biological and psychological processes
temporal resolution mean?
ability to record activity over time
spatial resolution
ability to accurately indicate location of activity
Single Cell Recordings
Insertion of micro-electrodes into the brain to record changes in individual cells.
Invasive
Temporal resolution: Wide ranging (ms to hours)
Spatial resolution: Limited (one cell)
Electroencephalography (EEG)
Measurements of electrical brain activity at scalp surface.
To magnify the small changes in electrical activity, the same stimulus is repeated. The associated signal can be extracted and averaged to produce a signal Event-related potential (ERP). Brain activity in response to stimulus can be identified and separated from background stimulus activity.
Key Uses: Due to excellent temporal resolution, invaluable in studies
of language.
Non-invasive
Temporal resolution: Excellent
Spatial resolution: Poor
Magneto-encephalography (MEG)
Measures the magnetic fields produced by brain activity at the skull.
Non-invasive
Temporal resolution: Excellent- ms level
Spatial resolution: Reduced distortion compared to EEG; magnetic fields are not distorted by the skull
Positron EmissionTomography (PET)
Detects positrons emitted from radioactive substances. Requires radioactive water to be injected into the body- which will move to active regions of the cortex. Detection of emitted positrons allows picture of active regions to be built up.
Invasive
Temporal resolution: Low: records activity over +60 sec
Spatial resolution: Reasonable: locates activity within 3-4 mm
functional Magnetic resonance imaging (fMRI)
Detects functionally induced changes in blood oxygenation in the brain. Subtraction technique: Brain activity during control task must be subtracted from brain activity during experimental task (Careful selection of a control task required).
An indirect measure: only looks at blood flow, not neural activity
Non-invasive
Temporal resolution: Poor: tracks over several seconds; indirect measure of activity
Spatial resolution: Excellent
Why are these not always accurate
Because Bennett, Baird, Miller &Wolford (2009) found activity in the dead salmon’s brain.
The study highlights the problems of multiple comparisons and false findings
Trans-cranial Magnetic Stimulation (TMS)
Simulates ‘temporary lesions’- magnetic pulse of current used to temporarily inhibit processing in an area.
Examine whether inhibiting a region interferes with a particular task.
Non-invasive
Temporal resolution: Poor, the length of the influence of TMS is not known precisely
Spatial resolution: Limited; the spatial area affected by TMS is fairly large
