Figure 4. Behavioral tests and dendrite spine morphology in p38 wt and p38^Kl/+ mice. (A) Evaluation of memory by object recognition test in p38 wt (n = 11) and p38^KI/+ (n = 9) mice. Recognition index values are shown as mean ? SEM. (B) Freezing response of p38 wt (n = 11) and p38^KI/+ (n = 9) mice during fear conditioning trials (tone + shock conditioning). Values of freezing are expressed as mean ? SEM. (C) Freezing response of p38 wt and p38^KI/+ mice to contextual exposure and to presentation of conditioned stimulus (tone) in a modified context 24 h following fear conditioning. Values of freezing are expressed as mean ? SEM. (D) T-maze spontaneous alternation for p38 wt (n = 11) and p38^KI/+ (n = 9). Values of spontaneous alternation are expressed as mean ? SEM. (E) Golgi staining of dendrites of adult pyramidal neurons in CA1 hippocampus p38 wt and p38^KI/+ mice. Representative images of dendritic fragments from p38 wt and p38^KI/+ mice. (F) Quantification of spine length (a), spine head width (b), and spine density (c) of Golgi stained neurons in p38 wt (n = 8) and p38^KI/+ mice (n = 7). Bars = 4 ?m.