4The Musical Brain Flashcards
Where is the transverse temporal gyrus (Heshl’s gyrus) situated?
In the area of primary auditory cortex in the lateral sulcus
What’s another name for a frequency map?
Tonotopic organisation
How many neurons does the average brain have?
About 100 billion
How do signals travel through the brain?
Neurons fire (using glucose & oxygen), sending electrical signals (action potentials) which release neurotransmitters (chemicals), which synapse & bind with post-synaptic receptors, causing next neuron to either fire, inhibit firing, or the transmitting neuron reuptakes neurotransmitter
There are 6 layers of neurons in the grey matter; what function does the white matter have?
Axons are combined into fibre tracts which link different brain areas
What is the Basal Ganglia responsible for?;
What about the Cerebellum?
Timing & motor sequencing;
Fine motor coordination & speaking
What does the Thalamus relay?;
Which nervous system is the Hypothalamus involved with?
Sensory & motor signals to the cortex;
Autonomic nervous system (links nervous & endocrine systems such as pituitary gland)
What is the Amygdala responsible for?;
What about the Hippocampus?;
Emotion & memory processing;
Memory & spatial navigation
Which parts of the brain are involved in performing music?;
Which part is employed for reading music?
Frontal lobe (planning & integration); motor cortex (movement production); sensory cortex (tactile feedback); Occipital lobe
Which brain regions are activated when listening to or recalling lyrics of music?
Broca’s area (speech production); Wernicke’s area (speech understanding); frontal & temporal lobes
Listening to familiar music activates which areas of the brain?
Hippocampus (memory retrieval including timbre); inferior frontal cortex; cerebellum (when tapping along)
In which regions are emotional responses processed?
Amygdala; cerebellar vermis; frontal lobes
How does a Connectionist view brain processing?
Many parts of the brain are interconnected (distributed processing)
In the 60’s, what evidence was found in regards to brain lateralisation?;
What did Bever & Chiarello (1974) find with musicians compared to nonmusicians?
That speech production & comprehension resided in the dominant (usually left) hemisphere; removal of right temporal lobe impaired music processing; left-ear advantage for melody recognition;
Musicians use an analytic strategy in left hemisphere; nonmusicians use holistic strategy in right hemisphere
More recent evidence shows music processing distributed across both hemispheres depending on what?
Musical properties & skills assessed
In more recent studies, what musical characteristics does evidence suggest are processed in the left hemisphere?;
What about the right hemisphere?;
What characteristics seem to be shared between both left & right?
Rhythmic groups & pattern sensitivity (rhythmic skills); “language-like” skills (sight reading & naming notes/pieces);
Beat tracking (metre); pitch & timbre recognition; melody representation; emotional responses;
Out of place chord (for music style); familiar melody recognition
What was the first neurological evidence to show regional specificity of brain function?
Brain damage in the case of Phineas Gage (1848)
When a professional musician suffered a temporo-parietal stroke leading to musical arrhythmia, what were the symptoms?
Impaired rhythmic discrimination & reproduction; preserved metre & melody; auditory modality
What can removal of or damage to the temporal lobe affect?
Music processing
What’s an example of a positive neurological disorder in regards to music?;
What’s a negative example?
Music triggers seizures; Musical impairment (i.e. amusia)
List the different types of Amusia
Receptive (affects perception); expressive (affects production); congenital (e.g tone deafness); acquired (e.g brain injury); selective (one aspect spared while another impaired, e.g tonality/contour)
What is receptive Amusia?
An inability to perceive music as music or distinguish one tone from another; music often sounds like noise (e.g sound of clanging pots & pans)
There are many different forms of selective impairment. Describe Agnosia;
Describe Aphasia;
Impaired recognition (of familiar tunes but retained sensitivity to melodic contour); Impaired speech (retained ability to compose; e.g Russian composer: Vissarion Shebalin);
What’s impaired with Alzheimer’s disease?;
What’s retained?
Speech & memory/recognition abilities;
Ability to sing & recognise familiar music & sensitivity to musical structure (e.g can tell when melody doesn’t resolve to tonic)
Describe Disassociation of Domains;
What does this imply?;
Why is it difficult to conclude absolutes in this regard?
Impairment in one domain but not another (e.g speech but not music);
Separate resources/brain areas for processing;
Task demands not always accounted for in designs (e.g different skills & behaviours for music & speech)
In the case of Double Disassociations (e.g 1 aphasic & 1 amusic), what’s not an issue when designing an experiment?
Task difficulty (but areas of overlap & impairment are often idiosyncratic)
In Patel’s (2005) study investigating melody & non-verbal aspects of speech, what was found with congenital amusic participants?;
What was retained?
They demonstrated poor sensitivity to pitch change in music & speech (e.g change of emphasised word in a phrase);
The ability to detect differences in meaning of intact spoken phrases
Apart from melody & nonverbal aspects of speech, what’s another way in which music & speech overlap?
Syntax (tones/words); misplaced word in a sentence, unexpected note in a melody
Patel hypothesised that Clinical Disassociations reflect damage to domain-specific representations used for musical & linguistic syntax, whereas Neuro-imaging results reflect what?
Activity related to general syntactic processing (same area may be activated in processing but what does it actually mean?)
What does TMS stand for?
What does this technique use?;
What’s the spatial & temporal resolution like?
Transcranial Magnetic Stimulation;
A localized magnetic field generator/coil to create a temporary ‘virtual lesion’ without any damage to the brain; disrupts electrical activity (fairly new);
Both can be good
What does PET stand for?
What’s involved in this technique?
Positron Emission Tomography;
A radioactive isotope (usually fluorine), is attached to a glucose molecule & injected into the blood stream. When a brain region is activated, there’s an uptake of glucose & radioactive fluorine. Radioactive fluorine atoms decay, emitting a positron (positively charged electron) which soon meets a negatively charged electron. They annihilate one another emitting a gamma ray, & the location of this is determined within a 3-dimensional grid
What are the pros & cons of PET?
Offers a direct & sensitive measure of activity (high temporal resolution); but images aren’t sharp because of the distance a positron has to travel before it meets an electron (poor spatial resolution)
What does MRI stand for?;
How does it work?;
What are the pros & cons?
Magnetic Resonance Imaging;
An intense magnetic field is used to align the magnetic fields of individual hydrogen atoms. A radiofrequency energy pulse is directed to the site, which alters the rate of spinning hydrogen nuclei. The energy emitted when these perturbed hydrogen nuclei return to their original orientations is measured;
Provides high resolution image of the brain’s anatomy; poor temporal resolution; only looks at structure
What does fMRI (functional magnetic resonance imaging) measure?;
What are the pros & cons?
Change in the proportion of oxygenated and deoxygenated hemoglobin in a brain region (BOLD effect) Good spatial resolution but poor temporal (2 second intervals)
What’s are CAt scans?;
Resolutions?
Tests that produce cross-sectional images of the body using X-rays and a computer to produce tomographic images (virtual ‘slices’) of specific areas of the brain;
Good spatial, temporal & contrast resolution
What does MEG stand for?;
What is it?;
What are the pros & cons?
Magnetoencephalography;
A functional neuroimaging technique which records magnetic fields produced by electrical currents occurring naturally in the brain;
Good temporal but poor spatial resolution; expensive
In a 1999 study investigating the neural correlates of pleasant (consonant) & unpleasant (dissonant) music, 6 versions of a novel melody was played with increasing levels of dissonant harmony and noise. What was used to measure participants responses?
PET scans & subjective rating of emotional quality of the music
Which area of the brain has been found to be enlarged with both musically trained adults & children after 29 months of instrumental musical training?
Anterior corpus callosum
What has been found with string players & keyboard players in relation to the motor area?
String players’ left hand fingers cortical representation enhanced; greater symmetry (ILPG in motor cortex area) in keyboard players
Which brain areas have shown enhancement in children following 15 months of instrumental lessons?
Motor, auditory, & other distributed & relative sensorimotor integration areas
Structural plasticity from musical training can occur in children until what age?;
What about functional brain plasticity?
7-10;
The earlier the better
What are some benefits of learning & playing an instrument?
Increased multi-modal neural connections; enhanced cognitive abilities (e.g auditory, motor, vocabulary); sensorimotor integration; transfer effects (e.g language skills, higher IQ); enhance cognitive abilities & protect them into aging
