Table 2.
Summary of the clinical signs typically associated with lesions in specific regions of the brain (adapted from [7])
| Fore brain: cerebral cortex and thalamus | Cerebellum |
|---|---|
| Seizures | Ataxia |
| Behavioural changes (loss of training, failure to recognise owner, aggression, hyperexcitability) | Tremor |
| Altered mental status (apathy, depression, disorientation, lethargy, coma) | Hypermetria |
| Abnormal movements, postures (circling, pacing, wandering, head-pressing) | Broad-based stance |
| Contralateral deficits: postural reactions, vision, menace response, facial sensation | Menace deficits + normal vision |
| No weakness | |
| Midbrain | Hypothalamus |
| Upper motor neuron paresis/paralysis all four limbs or contralateral to lesion | Normal gait |
| Postural reaction deficits all four limbs or contralateral to lesion | Altered mental status (disorientation, lethargy, coma) |
| Mental depression/coma | Changes in behaviour (aggression/hyperexcitability) |
| Ipsilateral oculomotor and trochlear deficits | Bilateral cranial nerve II deficits at optic chiasm |
| Hyperventilation | Abnormal movements/postures (tight circling, pacing, |
| wandering, head-pressing, trembling) | |
| Abnormal temperature regulation | |
| Abnormal appetite | |
| Endocrine disturbances | |
| Seizures | |
| Vestibular system (CNS component) | Brain stem |
| Head tilt | Ipsilateral hemiparesis/asymmetrical tetraparesis: |
| Nystagmus - positional, vertical, horizontal, rotary | Upper motor neuron signs |
| Ataxia | Ipsilateral postural reaction deficits |
| Postural reaction deficits | Cranial nerve abnormalities: V-VII, IX-XII |
| Altered mental status | Altered mental status: depression |
| Other cranial nerve signs | Irregular respiration |