tonic activity

Examples of tonic activity in the following topics:

• Classification of Neurons

  • Neurons that are typically constantly (or tonically) active are called tonic or regular spiking.
  • Neurons that are intermittently active are called phasic or bursting.
  • And finally neurons with high activity rates are called fast spiking.

• Transduction of Light

  • Photoreceptors in the retina continuously undergo tonic activity.
  • That is, they are always slightly active even when not stimulated by light.
  • In neurons that exhibit tonic activity, the absence of stimuli maintains a firing rate at an equilibrium; while some stimuli increase firing rate from the baseline, other stimuli decrease firing rate.
  • Thus, the visual system relies on changein retinal activity, rather than the absence or presence of activity, to encode visual signals for the brain.
  • When light strikes rhodopsin, the G-protein transducin is activated, which in turn activates phosphodiesterase.

• Osmoregulation

  • Tonicity is the ability of a solution to exert an osmotic pressure upon a membrane.
  • There are three types of tonicity: hypotonic, hypertonic, and isotonic.
  • Tonicity is a concern for all living things.
  • These fish actively take in salt through their gills and excrete diluted urine to rid themselves of excess water.
  • The turgor pressure within a plant cell depends on the tonicity of the solution in which it is bathed.

• Sheet of Blank Chromatic-Scale Clock Faces

  • Choruses most frequently (but not exclusively) begin on-tonic.
  • Verses (like strophes) tend to begin on-tonic.
  • A phrase or module is on-tonic when it begins with tonic harmony (I in root position).
  • A phrase or module is off-tonic when it begins on a harmony other than tonic.
  • The use of a non-tonic chord (usually dominant) at the end of a harmonically closed unit to transition into the beginning of the following on-tonic unit.

• Modulation

  • Tonicization occurs when a chord or short succession of chords are borrowed from another key in order to emphasize—or tonicize—a chord in the home key.
  • The principal difference between tonicization and modulation is the presence or absence of a cadence: tonicization does not incorporate a cadence in the tonicized key; modulation does incorporate at least one cadence (PAC, IAC, or HC) in a new key.
  • This often happens at phrase boundaries, with the old-key tonic ending one phrase and the new-key tonic beginning the next.
  • Direct/phrase modulations by step from old-key tonic to new-key tonic in pop music are also called step-up or pump-up modulations.
  • Tonicization is the process of momentarily emphasizing a non-tonic chord by using chords borrowed from the key in which that chord is tonic.

• Reflexes and Diagnosis

  • Assessment of reflex activity is useful in determining the health of the central nervous system.
  • While the reflexes above are stimulated mechanically, the term H-reflex refers to the analogous reflex stimulated electrically, and Tonic vibration reflex for those stimulated to vibration.
  • Doctors will typically grade the activity of a reflex on a scale from 0 to 4.

• Internal Expansions

  • Tonicization occurs when a chord or short succession of chords are borrowed from another key in order to emphasize—or tonicize—a chord in the home key.
  • The principal difference between tonicization and modulation is the presence or absence of a cadence: tonicization does not incorporate a cadence in the tonicized key; modulation does incorporate at least one cadence (PAC, IAC, or HC) in a new key.
  • This often happens at phrase boundaries, with the old-key tonic ending one phrase and the new-key tonic beginning the next.
  • Direct/phrase modulations by step from old-key tonic to new-key tonic in pop music are also called step-up or pump-up modulations.
  • A truck-driver modulation is a direct modulation that moves from the old key (usually the tonic chord) to the dominant chord of the new key to prepare that tonic arrival, again common in pop music.

• Tonal Center

  • It is also called the tonic, and it's the "do" in "do-re-mi".
  • (For more information about the tonic chord and its relationship to other chords in a key, please see Beginning Harmonic Analysis. )
  • Can you hear that they do not feel "done" until the final tonic is played?

• Hybrid Themes

  • Tonicization is the process of momentarily emphasizing a non-tonic chord by using chords borrowed from the key in which that chord is tonic.
  • The chord that is tonicized is typically a chord that belongs to the present key.
  • On the latter point, if the tonicized chord has tonic function in the current key (such as mi–sol–ti or la–do–mi), the applied chord will be an altered dominant of the current key.
  • If the tonicized chord has subdominant function in the current key, the applied chord will be an altered tonic of the current key.
  • We will use Roman numerals similarly when studying modulation to denote tonics of key areas to which the music modulates.

• Compound Themes

  • prolong tonic without a cadence (a classical presentation phrase, for example)
  • If the phrase prolongs tonic, the entire phrase should be placed within parentheses or curly brackets.
  • Half-cadence phrases end there.Authentic-cadence phrases continue on to a final tonic zone (usually a singe chord).
  • The (S) D T of the cadential progression will always stand on its own as a functional progression, and should never be placed in parentheses or brackets indicating tonic prolongation.
  • Keep in mind that every non-tonic chord inside those parentheses should have a postscript ("n" for neighbor chord, "p" for passing chord, etc., according to the pattern of the bass voice).