TABLE 1.
Summary of response rates from evoked potential studies.
| Percentage of responsive cells that were… | Percentage of total investigated cells that were… | ||||||||||||||||
| Authors | Species | Structure Stimulated | Bilateral or Unilateral Stimulation? | Number of units investigated | Percentage of non-responsive cells | Percentage of responsive cells | Inhibited | Excited | Biphasic | Responsive to one ganglion only | Responsive to both ganglia | Inhibited | Excited | Biphasic | Responsive to one ganglion only | Responsive to both ganglia | Comments |
| Reuss et al., 1984 | Rat | Habenular nuclei | Bilateral | 42 | 57.2% (n = 24) | 42.8% (n = 18) | 44.4% (n = 8) | 55.6% (n = 10) | Not described | Not described | Not described | 19% (n = 8) | 23.8% (n = 10) | Not described | Not described | Not described | 7 silent units were found. Confluens sinuum impaled with electrode. |
| Reuss et al., 1985b | Rat | SCG | Unilateral | 94 | 55.3% (n = 52) | 44.7% (n = 42) | 57.1% (n = 24) | 42.9% (n = 18) | Not described | Not described | Not described | 25.6% (n = 24) | 19.1% (n = 18) | Not described | N/A | N/A | 13 silent units were found. Confluens sinuum impaled with electrode. |
| Bilateral | 52 | 26.9% (n = 14) | 73.1% (n = 38) | Not described | Not described | Not described | 76.3% (n = 29) | 23.7% (n = 9) | Not described | Not described | Not described | 55.8% (n = 29) | 17.3% (n = 9)* | Confluens sinuum impaled with electrode. | |||
| Reyes-Vazquez et al., 1986 | Rat | SCG | Bilateral | 76 | 44.7% (n = 34) | 55.3% (n = 42) | Not described | 55.3% (n = 42) | Not described | Not described | Not described | Not described | 55.3% (n = 42) | Not described | Not described | Not described | 6 silent units were found. Sagittal sinus ligated. |
| Pazo and Gonzalez, 1991 | Rat | SCG | Unilateral | 19 | 53% (n = 10) | 47% (n = 9) | 56% (n = 5) | 33% (n = 3) | 11% (n = 1) | N/A | N/A | 26.3% (n = 5) | 26.3% (n = 5) | 5.3% (n = 1) | N/A | N/A | In some animals, the sagittal sinus was ligated |
| SCN | Unilateral | 19 | 47% (n = 9) | 53% (n = 10) | 50% (n = 5) | 30% (n = 3) | 20% (n = 2) | N/A | N/A | 26.3% (n = 5) | 15.8% (n = 3) | 10.5% (n = 2) | N/A | N/A | |||
| Stehle et al., 1987 | Hamster | SCG | Unilateral | 48 | 72% (n = 35) | 28% (n = 13) | 61.5% (n = 8) | 46.2% (n = 6) | Not described | N/A | N/A | 16% (n = 8) | 12% (n = 6) | Not described | N/A | N/A | Sagittal sinus ligated and cut. See notes** |
| Patel and Demaine, 1990 | Hamster | SCG | Both | 92 | 38% (n = 35) | 62% (n = 57) | 36.8% (n = 21) | 36.8% (n = 21) | 15.8% (n = 9)*** | Not described | Not described | 22.8% (n = 21) | 29.3% (n = 27) | 9.8% (n = 9) | Not described | Not described | No differences in form or magnitude of response found between unilateral vs bilateral or right vs left SCG stimulation. Confluens sinuum impaled with electrode. |
| Semm et al., 1981 | Guinea-pig | Lateral habenular nuclei | Bilateral | 128 | 56% (n = 72) | 44% (n = 56) | 44% (n = 56) | 20% (n = 11) | Not described | Not described | Not described | 35% (n = 45) | 9% (n = 11) | Not described | Not described | Not described | No mention is made of the confluens sinuum in the methodology. |
*7.7% (n = 4) of these cells showed different effects depending on whether left or right SCG was stimulated i.e., excitation or inhibition. Simultaneous stimulation showed no clear effects. **The number of units investigated in this study appears erroneous. This may possibly be due to a rounding error. ***This categorisation includes a population of cells which exhibited inconsistent responses following repeated stimulation.