Table 1.
A summary table over MCSF parameters for which there were significant differences between high and low drinking lines.
| Functional categories | Parameters | P versus NP | AA versus ANA | sP versus sNP | H1 versus L1 | H2 versus L2 |
|---|---|---|---|---|---|---|
| General activity | TOTACT | P < NP* | AA < ANA* | sP < sNP**** | ||
| FRQ TOTCORR | P < NP* | AA < ANA* | sP < sNP** | H2 >L2 * | ||
| FRQ CENTER | P < NP* | sP < sNP*** | ||||
| DUR CENTER | AA > ANA*** | |||||
| DUR/FRQ CENTER | P > NP* | AA > ANA* | sP > sNP ** | |||
| Exploratory activity | LAT LEAVE | P > NP** | AA > ANA**** | sP > sNP*** | ||
| DUR TOTCORR | P > NP* | sP > sNP*** | ||||
| DUR/FRQ TOTCORR | P > NP** | AA > ANA* | sP > sNP**** | |||
| LAT HURDLE | AA > ANA** | sP > sNP** | H2 < L2* | |||
| FRQ HURDLE | AA < ANA** | |||||
| DUR HURDLE | sP < sNP* | |||||
| DUR/FRQ HURDLE | AA > ANA** | sP < sNP** | H1 < L1*** | H2 < L2** | ||
| FRQ HEAD DIP | AA < ANA* | |||||
| # ZONES VISITED | sP < sNP** | |||||
| OCC VISIT ALL ZONES | sP < sNP### | |||||
| REARING | sP < sNP**** | |||||
| Risk assessment | LAT SLOPE | AA > ANA* | sP > sNP*** | H2 < L2* | ||
| FRQ SLOPE | AA < ANA** | sP < sNP**** | ||||
| DUR SLOPE | sP < sNP**** | |||||
| DUR/FRQ SLOPE | AA > ANA*** | |||||
| OCC SLOPE | sP < sNP## | |||||
| LAT BRIDGE ENTRANCE | AA > ANA* | sP > sNP*** | H2 < L2** | |||
| FRQ BRIDGE ENTRANCE | AA < ANA** | sP < sNP**** | ||||
| DUR BRIDGE ENTRANCE | sP < sNP** | |||||
| DUR/FRQ BRIDGE ENTRANCE | AA > ANA* | |||||
| OCC BRIDGE ENTRANCE | sP < sNP## | |||||
| SAP TO CENTER | sP > sNP** | |||||
| OCC SAP TO CENTER | sP > sNP## | |||||
| SAP TO SLOPE | sP > sNP**** | H2 < L2* | ||||
| Risk taking | LAT BRIDGE | AA > ANA* | sP > sNP** | H2 < L2** | ||
| FRQ BRIDGE | AA < ANA** | sP < sNP**** | ||||
| DUR BRIDGE | sP < sNP**** | |||||
| DUR/FRQ BRIDGE | AA > ANA* | |||||
| OCC BRIDGE | sP < sNP### | |||||
| FRQ CTRCI | AA > ANA* | sP < sNP* | H1 < L1* | |||
| DUR CTRCI | AA > ANA** | sP < sNP* | H1 < L1** | |||
| DUR/FRQ CTRCI | AA > ANA** | H1 < L1** | ||||
| OCC CTRCI | sP < sNP## | |||||
| Shelter seeking | LAT DCR | AA > ANA*** | ||||
| FRQ DCR | AA < ANA*** | |||||
| DUR DCR | AA < ANA* | |||||
| Anxiety-like behavior | DUR SHELTER/RISK INDEX | sP > sNP*** | ||||
| Impulsive-like behavior | SLOPE/BRIDGE INTERVAL | sP > sNP** |
Behavioral parameters, recorded during the 20-minute trial of the MCSF test, for which there were significant differences within the respective high and low drinking pair of selectively bred rats. Occurrence (OCC) indicates the zones that were not visited by all animals in each group or the behaviors that were not performed by all animals in each group (n = 12–16/group). The sum of frequencies to the three CORRIDORs (FRQ TOTCORR) and to all zones (TOTACT) was used for assessment of general locomotor activity. The total time spent in the three CORRIDORs was given the denomination DUR TOTCORR. The shelter/risk index is calculated from the difference in time spent in the dark corner room (DCR) and on the BRIDGE, relative to the total time spent in the two zones and is used as one way of interpreting anxiety-like behavior. A positive value indicates that the animals spent more time in the DCR than on the BRIDGE and is interpreted as higher anxiety-like behavior. The SLOPE/BRIDGE interval reveals how long time it takes the animals to enter the BRIDGE in relation to first entering the SLOPE and is here used as one way of interpreting impulsive-like behavior. Thus, a value close to zero indicates less risk assessment and a fast risk-taking response.
P ≤ 0.05,
P < 0.01,
P < 0.001,
P < 0.0001 comparing each pair of selectively bred rats (Mann–-Whitney U-test);
P 0.05,
P < 0.01,
P < 0.001 comparing each pair of selectively bred rats (Pearson Chi-square test). Raw data values are shown in Appendix S1. CTRCI = central circle; DCR = dark corner room; DUR = duration (s); DUR/FRQ = duration per visit (s); FRQ = frequency; LAT = latency (s); OCC = occurrence; SAP = stretched attend posture; TOTACT = total activity, i.e. the sum of all frequencies; TOTCORR = total corridor, i.e. the sum of all corridors.