Acute and chronic toxic encephalopathy on the other hand, are persistent changes in neurological function that typically occur with exposure to higher concentrations and longer durations respectively. The symptoms of acute and chronic toxic encephalopathy do not resolve with cessation of exposure and can include memory loss, dementia, small personality changes/increased irritability, insidious onset of concentration difficulties, headache, lightheadedness, ataxia, involuntary movements (parkinsonism), fatigue, seizures, arm strength problems, and depression. A paper by Feldman and colleagues described neurobehavioral effects in a 57-year-old house painter with regular exposure to large amounts of solvents.Magnetic Resonance Imaging (MRI) analyses have also demonstrated increased rates of dopamine synthesis in the putamen, reduced  anterior and total corpus callosum volume, demyelination in the parietal white matter, basal ganglia, and thalamus, as well as atypical activation of frontal areas of the brain due to neural compensation.The regions of interest on SPECT brain imaging include a majority of all cortical regions, and the globus pallidus in Carbon monoxide poisoning. Based on medical literature on SPECT brain imaging, signature patterns for toxic encephalopathy is a nonspecific patchy, diffuse pattern on the cortex, and sometimes is shown in subcortical regions, if exposure was severe.A thorough and standard diagnostic process is paramount with toxic encephalopathy, including a careful occupational, medication and medical history, standardized imaging and neuropsychological testing. Causes
In addition, chemicals, such as lead, that could instigate toxic encephalopathy are sometimes found in everyday products such as prescription drugs, cleaning products, building materials, pesticides, air fresheners, and even perfumes.
Taylor & Francis. ISBN 9997625897. Baker, Edward L. (May 2008). "Chronic toxic encephalopathy caused by occupational solvent exposure". Annals of Neurology. 63 (5): 545–547. doi:10.1002/ana.21394. PMID 18409195. S2CID 41546628. Feldman, R G; Ratner, M H; Ptak, T (May 1999). "Chronic toxic encephalopathy in a painter exposed to mixed solvents". Environmental Health Perspectives. 107 (5): 417–422. doi:10.1289/ehp.99107417. PMC 1566426. PMID 10210698. Encephalopathy Associated with Psychotropic Drug Therapy Yuji Odagaki Department of Psychiatry, Faculty of Medicine, Saitama Medical University Department of Psychiatry, Moro Hospital Japan

External links
NINDS Encephalopathy Information Page
Encephalopathy Causes, Symptoms, Diagnosis and Treatment by MedicineNet