People with HIV are less able to recognise facial emotion than non-infected people finds a study published in the launch edition of BioMed Central's open access journal BMC Psychology. Reduction in their ability to recognise fear in others is linked to a similar loss in immediate recall, while those with a lower general neurocognitive performance also had a reduced ability to recognise happiness.

The mechanism behind recognition of facial emotion is complex, involving many different areas of the brain, including the frontostriatal pathway and amygdala. The frontostriatal pathway is essential for learning and behavioural adaption, while the amygdale is involved in memory and emotion. The loss of this ability can be debilitating, impacting daily life and personal interactions.

Comparing people with HIV to a control group without HIV, researchers from the Catholic University of the Sacred Heart in Rome discovered that from the six basic expressions of emotion (disgust, anger, fear, happiness, surprise, sadness) that fear is the most difficult emotion to recognise. People with HIV were less accurate in identifying fearful expressions than the controls and also tended to have difficulties in immediate recall of words indicating a link between the two.

People with a higher number of AIDS-related events, such as pneumonia, Kaposi's sarcoma, or tuberculosis, and people with neurocognitive problems in memory, attention and decision making, language and speed of mental processing, were less able to recognise happiness in others.

Dr Eleonora Baldonero, who led the study commented, "The severity of HIV-associated neurocognitive disorders has been significantly reduced thanks to combination antiretroviral therapy. Nevertheless our research highlights a link between cognition and facial recognition and that AIDS-related events affect both. Understanding this on a individual level can help the long-term personal management of HIV."