Methods of Studying Behavior

Open Field Test A measure of general activity. In automated versions infrared sensors or video tracking is used to obtain precise measures of activity. In older tests, a grid is drawn on the floor and the experimenter would score the number of grid crossings.

Elevated Plus Maze Used mostly as a measure of anxiety. The time that an animal spends in the enclosed arm and open arms is recorded by hand (stopwatch) or video system. Anxious animals spend more time in the enclosed arms and less time on the open arms.

Behavioral Phenotyping Using a battery of behavioral tests to assess multiple functions. Comparison across different tasks that differ in several ways (motor, sensory, motivational etc.) may be like comparing apples and oranges. Functional behavioral phenotyping – hold everything constant across tasks except for the Independent Variable What’s wrong with my genetically altered mouse Neuropsychological Tests Behavioral tests performed with humans (sometimes to determine likely sites of brain damage) Probabilistic classification – habit formation WAIS – general intelligence Wisconsin card sort – frontal lobe function

Radial Arm Maze Food pellets are placed at the end of each arm. In the win-shift task, animals have to remember which arms they have been to (using spatial cues) and avoid re-entering those arms (errors).

Cued Win-Stay Task

Paired Unpaired TrainingTesting Conditioned Cue Preference Task

Hippocampal lesions impair spatial win-shift Amygdala lesions impair CCP impair CCP Dorso-lateral striatal lesions impair cued win-stay

The Morris water maze PubMed Search 2/25/05

The Morris water maze Search done today, 3/29/10 = 5,253 hits

The Morris water maze

Trial 40 – Control rat

Top View (camera) Side view Standard Water Maze Setup Submerged platform # Quadrant Start points Target Annulus L Zone Water level CBA Non-targetAnnuli

Dependent Measures Place learning (acquisition) Escapelatency Escape latency – time (sec) to reach the platform Distance Distance – length (cm) of swim path Heading angle Heading angle – deviation (deg) from a direct path Cumulative distance Cumulative distance – cumulative average deviation (proximity to the goal in cm) from a direct path Probe test – spatial memory (retention) Quadrant time Quadrant time – % time (sec) in each quadrant Annulus crossings Annulus crossings – number of passes through target and non-target annuli (= or 2x surface area of platform) Proximity Proximity – average distance (cm) from target and non-target annuli Distance Distance – path length (cm) in each quadrant Thigmotaxis Thigmotaxis – swimming near wall – % time (sec) in outer zone General performance measures Swim speed Swim speed – cm/sec

Place Learning

Probe test without platform (60 sec)

DorsalHippocampus Adapted from Swanson (1992)Formol-thionin stain Level 28 of 73 Swanson, L.W. (1992). Brain Maps: Structure of the Rat Brain. Amsterdam: Elsevier. Coronal section Hippocampus

Adapted from Swanson (1992)Cresyl violet stain Swanson, L.W. (1992). Brain Maps: Structure of the Rat Brain. Amsterdam: Elsevier. Level 14 of 73Coronal section Caudate-putamen complex

Devan, Goad & Petri (Neurobiol Learn Mem; 1996, 66:305-23) Extent of damage from electrolytic lesions: Minimum – rising- right hatching Maximum – rising- left hatching Caudate-putamenFornix/fimbria

Devan, Goad & Petri (Neurobiol Learn Mem; 1996, 66:305-23) ControlCPuFF