Objective Patterns of Face Recognition Deficits in 165 Adults with Self-Reported Developmental Prosopagnosia

Abstract

In the last 15 years, increasing numbers of individuals have self-referred to research laboratories in the belief that they experience severe everyday difficulties with face recognition. The condition “developmental prosopagnosia” (DP) is typically diagnosed when impairment is identified on at least two objective face-processing tests, usually involving assessments of face perception, unfamiliar face memory, and famous face recognition. While existing evidence suggests that some individuals may have a mnemonic form of prosopagnosia, it is also possible that other subtypes exist. The current study assessed 165 adults who believe they experience DP, and 38% of the sample were impaired on at least two of the tests outlined above. While statistical dissociations between face perception and face memory were only observed in four cases, a further 25% of the sample displayed dissociations between impaired famous face recognition and intact short-term unfamiliar face memory and face perception. We discuss whether this pattern of findings reflects (a) limitations within dominant diagnostic tests and protocols, (b) a less severe form of DP, or (c) a currently unrecognized but prevalent form of the condition that affects long-term face memory, familiar face recognition or semantic processing.

Diagnosing developmental prosopagnosia: repeat assessment using the Cambridge Face Memory Test

“…= 15.05) visited the university for initial testing. These 30 participants were recruited from a pool of 128 individuals (see [21]), who had been screened for DP in person and were invited to take part in the current study. Forty others (32 female, M age at initial testing = 52.03 years, s.d.…”

“…not relying on a single score on a single test) reduces ‘the chance that it happened by chance’ [ 20 , p. 945] and is vital for minimizing false alarms. However, this protocol does not allow for the possibility that the three assessment tasks measure different sub-components of face-processing that may be selectively impaired [ 21 ]. That is, while allowing for some overlap in processes on the three tasks (i.e.…”

“…all three arguably tap face perception to some degree), it is broadly accepted that the CFMT assesses short-term, unfamiliar face memory [ 22 ], famous face tests measure long-term face memory and/or semantics and naming [ 23 , 24 ], whereas the CFPT is predominantly a measure of face perception [ 15 ]. By only diagnosing DP when two (or more) of these sub-processes are impaired, individuals who may be impaired on only one process are rejected (for example cases see [ 21 ]), and the possibility that intact performance may occur by chance on a single administration of each task is not accommodated.…”

The Scanpaths of Subjects with Developmental Prosopagnosia during a Face Memory Task

“…As there may be heterogeneity within developmental prosopagnosia [28,55,56], and to ensure that group averaging did not obscure any individually anomalous patterns, we also performed a single-subject analysis for all the above indices, comparing each subject’s data to 95% prediction intervals derived from control data.…”

Normal recognition of famous voices in developmental prosopagnosia

“…In the present study we sought to determine whether adults with DP show impaired recognition of celebrity voices. Famous face recognition tasks are thought to reveal the face processing problems in DP more effectively than unfamiliar face matching tasks 4 . Typical individuals are thought to have stored representations for thousands of familiar faces 61 .…”