neurobiology
The Neuroscience of Meditation
Meditation is different from rest or sleep. It’s a wakeful hypometabolic state with lowered sympathetic activity as opposed to the fight and flight reactions which requires an active sympathetic system. Parasympathetic activity is increased which is important for relaxation and rest. This increase of parasympathetic state is characterized by reduced heart rate, lower systolic blood pressure, lower oxygen metabolism, and an increase of skin resistance. So it’s not only a rest state but also physiological relaxation related to to stress relief.
But what is the effect of meditation on the brain?
During meditation not only general relaxation is experienced but also a reduction of mental activity and positive affect. During meditation the reduced mental activity is mediated by increased activation of networks of internalized attention which trigger the activity in regions that mediate positive emotions. Networks related to external attention and irrelevant processes are decreased in activity.
The networks activated for internal attention and positive mood are mainly located in the frontal and subcortical brain regions. The positive affect more specifically increases the activity in the left prefrontal and limbic region of the brain. The internal focused attention is thought to originate in an activation of frontal and thalamic region of the brain. There’s also some evidence that experienced meditators show these activations and deactivations in a greater extend compared to novices in the field of meditation.
In conclusion, there is converging evidence that fronto-parietal and fronto-limbic brain networks seem to be activated in the attention practices that lead to Meditation, presumably reflecting processes of internalised sustained attention and emotion regulation.
One should keep in mind that these findings relate to meditation in general. Different kinds of meditations can result in slightly different activation and deactivation patterns. Different brain activation networks can thus be activated by different Meditation traditions. These findings mostly result from comparison of small groups of experienced meditators compared to novices.
Rubia, K. (2009). The neurobiology of Meditation and its clinical effectiveness in psychiatric disorders Biological Psychology, 82 (1), 1-11 DOI: 10.1016/j.biopsycho.2009.04.003
The Neuroscience of Jazz
Improvisation is the main feature of Jazz that distinguishes it from other forms of music making. Improvisation is the spontaneous musical performance within a relevant musical context. It consists of novel melodic, harmonic and rhythmic musical elements. This unique feature of jazz offers the opportunity for neurobiological research or even creativity. What they did was do a functional MRI brain scan on 6 highly skilled professional jazz musicians.
These jazz musicians had to play a simple musical tune and an improvisation on this tune with the restriction to the use of C major scale quarter notes within the same octave of the simple tune. Next they had to play a memorized original jazz composition with the accompagnement of a pre-recorded jazz quartet followed by an improvisation of the memorized composition. In order to compare brain activity during these two conditions. Everything was recorded, the music and finger/hand movements. The participants used a keyboard in the fMRI without iron.
Spontaneous improvisation was in each case associated with a highly congruous pattern of activations and deactivations in prefrontal cortex, sensorimotor and limbic regions of the brain. In addition, the majority of these regions showed functionally reciprocal patterns of activity. That is, activations during improvisation were matched by deactivations during the control tasks, and vice versa, when each condition was compared to the resting baseline.
The prefrontal cortex was characterized by a deactivation during improvisation, sensorimotor activity in the sensory cortex area were mostly activated, and a widespread deactivation of the limbic and paralimbic region during improvisation. These deactivation of limbic and paralimbic regions were seen in the amygdala, hippocampus and hypothalamus and other structures of this region.
The changes in the prefrontal cortex consisted of a deactivation in the lateral parts and activation in the medial parts of the prefrontal cortex. The medial part is thought to play a role in the complex phenomenon of the self, internally motivated self generated content and as such this activation can be explained by the fact that improvisation is also a way of expressing one’s own musical voice or story. The deactivation of the lateral part is explained by the occurrence of free floating attention, permitting spontaneous expressions without interference of self-monitoring.
Activation of the sensorimotor regions is explained by the complex acoustic and sensory stimuli during improvisation on the keyboard. The hardest to explain is the widespread deactivation of the limbic structures who are associated with emotions. Deactivation of amygdala and hippocampus has been associated with the perception of music that is nice to the ears or elicits intense pleasure. This doesn’t explain the deactivation in other limbic structures.
Limb CJ, & Braun AR (2008). Neural substrates of spontaneous musical performance: an FMRI study of jazz improvisation. PloS one, 3 (2) PMID: 18301756
DIETRICH, A. (2004). Neurocognitive mechanisms underlying the experience of flow Consciousness and Cognition, 13 (4), 746-761 DOI: 10.1016/j.concog.2004.07.002
The Neurobiology of Love
Previously we discussed the neurobiology of falling in love. But this is only the beginning, the process of attraction followed by the attachment process. This process can develop and last for a while or in some cases for ever. Biologically is falling in love the first step in pair formation.
Falling in love is more accompanied by arousal and more pronounced behavior, “the madness of falling in love” as it is sometimes called. This should be distinguished but not completely from later stages of love or long lasting relationships. Moreover, falling in love is accompanied by stress reactions such as activation of stress system in the central nervous system with activation of cortisol metabolism.
In contrast to the phase of falling in love is motherly love, mother’s love for her child. It’s the most accepted form of love, an enduring social bond. Maternal and romantic love are not all the same, there is specific overlapping activity in the central nervous system as well as differences mostly in activity. Maternal and romantic love share the pattern of cortical de-activation in particular the frontal cortex. This might account for the somewhat suspended judgment when it concerns their own children. Mothers as well as lovers are a good deal more patient and less critical when it’s about their children or loved one respectively. In maternal love there is a strong activation of parts of the brain that are specific for faces. This is for the importance of reading children’s facial expressions, to ensure their well being, and therefore the constant attention of the mother for the face of the child. Another difference is the involvement of the hypothalamus only in romantic love not in maternal love, since the hypothalamus is associated with sexual arousal.
This brings us to another form of love, the more sensual, sexual part. Sex is closely related to attachment but is not always synonymous with romantic love. Sexual activity can occur in the absence of social attachment, and many forms of attachment exist that do not involve sexual behaviors.
The Neurobiology of Love in a nutshell
The areas that are involved are, in the cortex, the medial insula, anterior cingulate, and hippocampus and, in the subcortex, parts of the striatum and probably also the nucleus accumbens, which together constitute core regions of the reward system…….the areas that are activated in response to romantic feelings are largely coextensive with those brain regions that contain high concentrations of a neuro-modulator that is associated with reward, desire, addiction and euphoric states, namely dopamine. Like two other modulators that are linked to romantic love, oxytocin and vasopressin
This figure above points to some of the most but not all brain regions involved with the neurobiology of love.
Further reading
If these scribbles got you interested in the subject the articles on which this writing is based are freely available for down load:
White Women Looking For Black Men (PDF), Tobias Esch & George B. Stefano, Neuroendocrinol Lett 2005; 26(3):175–192 PMID: 1599071.
Or
Minireview: The neurobiology of love (PDF), S. Zeki, FEBS Letters 581 (2007) 2575–2579
ZEKI, S. (2007). The neurobiology of love FEBS Letters, 581 (14), 2575-2579 DOI: 10.1016/j.febslet.2007.03.094
Esch T, & Stefano GB (2005). The Neurobiology of Love. Neuro endocrinology letters, 26 (3), 175-92 PMID: 15990719