LECTURE 2- NEUROPSYCHOLOGY Flashcards
What is neuropsychology?
- Studying the effects of brain damage on cognition
- Studies stokes or CVAs/ traumatic head injuries/ tumours/ viral infections/ neurodegenerative disorders.
- The data collected is behavioural
- No experimental control over lesions
What is aspiration?
A type of experimental lesion
aspirating brain regions using a suction device and applying a strong current at the end of an electrode tip
What is Transection?
a type of experimental lesion
cutting off discrete white matter bundles
what is a neurochemical lesion?
a type of experimental lesion
toxins are taken up by selective NT systems and create chemical reactions that kill the cell
What is a reversible lesion
a type of experimental lesion
pharmacological manipulations can sometimes produce reversible functional lesions. E.g. cooling parts of the brain
What is TMS?
Transcranial magentic stimulation
- A change in electrical current in a wire generates a magnetic field- magnetic field can induce a secondary electrical current, in the neurons below the stimulation site.
- Used to investigate the timing of cognition as well as location of cognition known as a ‘virtual lesion’
- It can only stimulate certain regions
What is TDS
Transcranial direct current stimulation
* This uses a weak electric current applied between 2 electrodes
* A stimulating pad is placed over the region of interest and the other pad is placed in a site if no interest whilst a cognitive task is performed- anodal and cathodal stimulation I directly contrasted
* Cathodal tDCS Decreases cortical excitability and decreases performance
* Anodal tDCS Increases cortical excitability and increases performance
* Can enhance or impair performance
* Low spatial resolution and poor temporal resolution
Genotype first approach
An analysis approach in which different genotypes (e.g. different alleles) are used to explore for phenotypic variation
E.g., a genetic variant may be known to encode the mu-opioid receptor which is
related to susceptibility to physical pain
phenotype first approach
An analysis approach in which different phenotypes are used to explore genetic differences
Genome-wide association study
) A phenotype-first approach in which the presence/absence, or continuous variation, in a trait is linked to variations at many different sites in the genetic code
What is a Neurocrine difference?
Hormones
* Correlational approach that can be adapted to examine causation
* Hormone differences in blood or saliva may not reflect those in the brain; hormone levels are naturally very variable.
how can we measure genes via herediability?
Conventionally, heritability is estimated by studying similarities
and differences between individuals who share their genes to
varying degrees:
– family studies – between parent and child, siblings, or between other
family members
– twin studies – between identical (monozygotic) twins and non-identical
(dizygotic) twins
– adoption studies – between adopted children & biological/adoptive parent
